alt.hn

5/18/2025 at 6:07:03 PM

Building my own solar power system

 https://medium.com/@joe_5312/pg-e-sucks-or-how-i-learned-to-stop-worrying-and-love-building-my-own-solar-system-acf0c9f03f3b

by JKCalhoun

5/21/2025 at 12:47:30 PM

I’ve been running a solar microgrid on my coffee farm for the last 7years. We started with a few golf cart batteries and 4 panels, these days we’re powering 4 houses, 7 cabins, water extraction, treatment, and RO processing, campus-wide fiber network and switches, path lighting, security systems, and a small server rack.

We’re running 6 inverters on our primary system in a three phase configuration, 35kw of panels and 160kwh of lithium iron batteries. About to add an additional 20kw of panels and a test bank of LiTo cells.

Our panels are a distributed set of rooftop mounted panels on various buildings, which also serves to shade the rooftops reducing cooling loads.

We still have to run a generator to supplement charging on dark overcast days, but it’s typically about 100 hours a year. Hooping to get that running on biomass eventually.

It’s strange to me that people in rural areas pay for electricity. It makes no economic sense, at least here in the Caribbean.

by K0balt

5/21/2025 at 1:17:20 PM

> It’s strange to me that people in rural areas pay for electricity. It makes no economic sense, at least here in the Caribbean.

This comment was very confusing until I read the second sentence. Electricity prices in the Caribbean are very high, and I can only imagine that rural areas are even worse.

Where I’m at in the United States a typical electric rate is around $0.10/kWh. Paying that nominal amount and avoiding the need to service additional equipment and deal with backup generators is an easy decision.

by Aurornis

5/21/2025 at 1:48:57 PM

You’re in a good part of the country for grid power. I’m in Georgia where the typical rate is about 14 cents but summer rates are more like 18. Summer rates aren’t captured in this EIA chart but you can see the whole country. With summer rates and high energy use for cooling and dehumidification it’s a 7-8 year payback for a 13kW DC/10kW AC system.

https://www.eia.gov/electricity/monthly/epm_table_grapher.ph...

by Moto7451

5/21/2025 at 1:42:55 PM

I’m jealous. Where I live in California the off peak rate is $0.32/kWh and peak rates are $0.58/kWh.

by nullpoint420

5/21/2025 at 1:50:29 PM

Rural area power co-op member here - flat rate 24/7 for residential is .13/kWh. Businesses/farms can get down to .10/kWh if they qualify.

They proposed to update it to .15 so they could trim trees around the lines a little better, but it got denied by the co-op members as unnecessary.

by Loughla

5/21/2025 at 2:28:38 PM

> They proposed to update it to .15 so they could trim trees around the lines a little better, but it got denied by the co-op members as unnecessary.

Pge felt the same way and it did t turn out so well for them. I hope your coop is never found to be at fault for the next record breaking fire…

by baby_souffle

5/21/2025 at 2:44:15 PM

So the increase was to buy spray equipment to attach to a helicopter. And a helicopter. One of the co-op ex-board members' son recently moved back to the area and had his license. . . It was a shameless cash grab by that family and was rightfully voted down by a wild majority of the co-op members. Every member of the board was replaced within 2 years of them proposing the increase as well.

They currently keep all the lines clear via bucket trucks, and when they spray, they use ATV's and trucks. It takes most of June to spray all the lines, but they get it done easily.

The actual physical infrastructure has been replaced almost entirely in the last 10 years through federal and/or state grants in combination with income from power charges.

Also, these are just fundamentally different entities. PGE is a private entity that operates for a profit. Our power company is a co-op owned and run by its members. If they have any profit at the end of the year (once infrastructure improvements and safety net investments are paid for), the money gets paid directly back to the co-op members. It's a WILDLY different incentive structure.

by Loughla

5/21/2025 at 4:48:43 PM

Not every place is built in a dry forest which traditionally burned regularly but the current infrastructure is built around never burning. The only risk in, say, Michigan, is the power going out at inopportune times.

by coryrc

5/21/2025 at 2:12:30 PM

If that's considered high, I'm just not going to say what it costs in the Caribbean.

At least where I was.

by bilbo0s

5/21/2025 at 6:05:51 PM

I'm in the Bay Area - Off peak is 0.44 and peak is 0.48

Separately for "clean power", Off peak is 0.13 and peak is 0.17

So that's a combined 0.57 and 0.65

by supportengineer

5/21/2025 at 2:39:54 PM

$0.08/kWh here for central Illinois

by Evidlo

5/21/2025 at 3:15:58 PM

Taxes and supply charges are what take it from cheap to expensive in Illinois.

by ComputerGuru

5/21/2025 at 6:07:48 PM

Yep, and we have 5 nuke power plants in vicinity

by robohoe

5/21/2025 at 5:37:26 PM

Doesn’t that sort of rate make the payoff for a solar system install just a few years?

by horacemorace

5/21/2025 at 9:44:11 PM

Yeah - even with PGE trying their best to screw over solar customers in the last few years, I figure we've at least gotten our money back in ~15 years of owning a ~4KW system. Something like 75 MW generated in that time, assuming the inverter is more-or-less correct. At this point, doesn't make any sense anymore, since they only credit you like $0.1 and charge you $0.6 (I haven't looked too closely at it) - you'd have to generate 5-10x your consumption to mostly offset it.

We bought ours in '10 to offset high AC use in the summer - we were paying $1000-1500 a month for 2-4 months in the summer. The first few years, our "year-end" balance was < $1K (we just paid minimum payments the rest of the year), so I figure we easily saved $2-3K/year in those early years, and after the incentives in those days, we paid ~$14K, so maybe 7 years to pay it off. Our year-end balance was more like $3K the last time, and I think we're still producing 80-90% the same power, but PGE keeps changing the plans around. At this point, I'm interested in upgrading our cells from 300W to 450W, but I'd only do that with a battery system that also stores energy so that we could go more or less entirely off-grid. But probably need a new roof first..

by hn_acc1

5/21/2025 at 6:09:03 PM

> I’m jealous. Where I live in California the off peak rate is $0.32/kWh and peak rates are $0.58/kWh.

My California rates are .50/63 off/on peak

"Jealous" is not the term I'd use...

by w10-1

5/21/2025 at 3:03:52 PM

In Quebec, I'm paying $0.069/kWh or USD $0.05/kWh (hydroelectric, so already green), so it's hard to make a case for solar.

by gramie

5/21/2025 at 6:02:00 PM

> hydroelectric, so already green

Not so fast. Zero emissions, yeah. But they have damaged the habitat for some bird species.

by gosub100

5/21/2025 at 9:34:08 PM

Would love to see your analysis of Thanksgiving

by singleshot_

5/21/2025 at 10:13:16 PM

A colossal positive impact, with the population of the turkeys skyrocketing.

by nine_k

5/22/2025 at 1:30:56 AM

You mean the turkey voluntary extinction movement?

by hansvm

5/22/2025 at 12:17:38 PM

Doesn't affect their habitat at all.

by gosub100

5/21/2025 at 7:02:41 PM

Feral cats kill 2 billion birds a year, FYI the green energy kills birds thing is a right wing talking point designed to distract and delay. All human activity kills some nominal number of birds

by aplummer

5/21/2025 at 10:19:19 PM

Indeed. They care about the environment when pretending to do so lets them fight against things which are actually good for the environment and bad for the fossil fuel industry.

by RajT88

5/22/2025 at 12:18:30 PM

Whataboutism arguments kill 2 million discussions per year by avoiding refutation of the central point.

by gosub100

5/22/2025 at 10:53:06 AM

I’m in a mountain town in BC Canada and pay $0.13/kWh. My 7.8kW solar system cost me $0 out of pocket after incentives and an interest free loan. It’s making ~$1000 per year of electricity, so we’ll just put that onto the loan for the next 8 years instead of paying it to the power company. Then for ~25 years after that it will make me $1000/year. Free money.

(The price of electricity is already pre-approved to increase 5% a year, so actually my savings will be more every year than the year before)

Solar can be worth it even when power is cheap.

by testing22321

5/22/2025 at 9:52:35 PM

Why pay off an interest free loan?

by Scoundreller

5/23/2025 at 9:12:17 AM

It has to be paid off in 10 years.

by testing22321

5/21/2025 at 8:03:18 PM

I'm in the Canadian prairies and we pay a similar electric rate. It's funny though...

> avoiding the need to service additional equipment and deal with backup generators is an easy decision.

We've got a house in a very small town (pop. 100) and there are solar panels on a ton of the houses there. I've asked a few people about it and it's 100% for grid redundancy. Sure, they save a bit of money on their power bill, but they're basically using the panels and batteries as an alternative to a backup generator. Winters are quite cold here and having enough power to run the natural-gas-fired furnace and a few light bulbs is a huge win when the power inevitably goes out. Lots of people have small generators kicking around too (like the Honda EU2200 that RV folks love) but the solar install has seriously cut down on the need for those.

by tonyarkles

5/21/2025 at 3:40:14 PM

$0.10 kwh is low for most of the US. Can I guess.... Western state or PNW?

by jorblumesea

5/21/2025 at 4:08:30 PM

Over here in PA I pay $0.095, so nine and a half cents, per KWh for electric supply, but then I pay that same amount for transmission, so it's functionally 19 cents per KWh, but maybe the person you're replying to isn't counting transmission fees?

by entropicdrifter

5/21/2025 at 4:19:42 PM

Similar here in Maine under CMP. Something like 12.5 cents/Kwh, but with the delivery aspect factored in it's basically 28 cents/Kwh.

I always assume when people on here are talking their 'rates', that they are usually NOT factoring in the delivery fee unless stated.

But maybe some places are just really THAT cheap.

by brewtide

5/21/2025 at 6:38:11 PM

I pay 11.6 cents per kilowatt hour inclusive of everything (taxes too). My household used 647 kilowatt hours in April and the bill for the month was $75.02. The per-unit charge neglecting taxes and delivery is only 7.4 cents. This is in Washington state.

by philipkglass

5/21/2025 at 6:37:05 PM

I don't know why anyone would not include the "delivery" fee, I think it really is that cheap in many places in the US.

Here in NYC the "supply" charge is much less than half of the total bill. If I add up all the fees and surcharges and taxes etc, the total ends up around 35 cents / KWh, which I thought was rather high until I heard about California ...

by ploxiln

5/22/2025 at 4:42:08 PM

I pay around 10 cents per kWh in the southern US; we have a nearby nuclear plant. We do have a base fee just for the meter, but no separate transmission fee. My in-laws in Texas have an open market for generation but pay transmission separately.

by devilbunny

5/21/2025 at 6:49:47 PM

why would you not include the transmission? residential customers just pay one bill and that's including the lines, maintenance.

In western states such as Oregon, Washington, it is actually 0.12KWH including transmission.

by jorblumesea

5/21/2025 at 2:36:46 PM

How has your experience been with the lithium-titanium-oxide batteries? Everything I read makes it sound like the optimal solution for safety and long life, but it doesn't seem like they have displaced other battery chemistries very much.

by rz2k

5/22/2025 at 2:30:03 AM

I’m excited to try them too… I’ll get back to you in 5 years lol.

by K0balt

5/21/2025 at 4:06:17 PM

For the US, the entire user base helps subsidize rural customers. I have recently had the thought that I'm curious how this subsidy compares to the price of creating local micro-grids for rural communities. Especially in places like California where it is long distance power lines running to rural communities that have started several major fires.

I don't have the skill to do it myself, but I'd love to see an analysis of whether it would make more sense at this point to do solar/wind + batteries and backup generators for at least the smallest and most remote communities.

by MostlyStable

5/22/2025 at 7:28:47 AM

The Scottish island of Eigg has its own micro grid built by the residents which works like this.

by pjc50

5/21/2025 at 2:05:01 PM

What is your recovery plan in the event of a hurricane?

I'm not fond of high electric rates, but in addition to generation those rates amortize and distribute the cost of storm recovery. A home or business with grid-tied solar pays interconnect fees for the option to get paid back a little for excess generation, and the option to decide to switch back to 100% grid power if a storm damages the on-site panels.

by thebiss

5/21/2025 at 2:27:18 PM

> those rates amortize and distribute the cost of storm recovery

Not exactly when it is a farm out there away from a town.

My experience is from a different era (90s) and a different kind of farm, but I spent a bunch of summers in one, which had power outages whenever the monsoons picked up.

The trouble was that there was a single line feeding the farm from about 6km away, so if that went down a single farmowner complained - the rate payers who were in a denser urban area always got priority, because there were 600+ people who shared a transformer.

The generator ran a lot when winds knocked power out, but the generator only ran when there was a big power need like running the well pumps or one of the winnowing mills. Even the winnower had pedals, because work doesn't stop.

Every bathroom had a light with a 30 minute battery in it, which came on when the power went out - I guess if they had LEDs those same batteries would be 6 hour lights.

They would have killed for solar + storage, because shipping fuel in for the generator was one of those annoying things you had to keep doing over and over again.

by gopalv

5/21/2025 at 6:06:34 PM

>The trouble was that there was a single line feeding the farm from about 6km away, so if that went down a single farmowner complained - the rate payers who were in a denser urban area always got priority, because there were 600+ people who shared a transformer.

The urban rate payers also subsidize the rural ones, so it makes sense that they'd be front of the line.

by p_j_w

5/22/2025 at 4:48:34 PM

I would have thought an isolated farm would have had propane on site - likely more than one tank.

I don’t worry about outages much in my current home because the main line to ~1000 houses goes right past me, and I’m fed straight from it. If I’m out, it’s a very high priority line. Worst ever was about two days. It helps that our worst storms are usually in spring, so weather is mild.

by devilbunny

5/21/2025 at 2:33:22 PM

After a hurricane, the plan might be to help neighbors charge their phones, or sell electricity to telcos to power their networks switches and cell towers.

I think I am much less remote than the poster, and I can easily lose power for a week or more after a winter storm. Considering that they already have generators on site that can manage the full load, they probably have much better up time than the utility electricity provider.

by rz2k

5/22/2025 at 2:34:44 AM

All underground infrastructure or in concrete utility huts. Powerplant is concrete, no flooding issues due to excellent drainage of the area.

We can run on generator to charge the batteries for about 2 weeks on the fuel we keep. Other than that, we rebuild what isn’t broken and later buy more panels. Most of our mounts should be good to about 150mph, but trees also fly so?

Good news is we can buy panels here about $120 for a 500 watt panel.

Also we have some geographic protection from the full brunt of a storm , as we are in a mountainous eddy zone that typically sees about 30 percent of the coastal and mountaintop wind speed when a cyclone passes nearby as they frequently do.

by K0balt

5/21/2025 at 12:52:27 PM

Would imagine it's the initial cost of seeing all that up, and then the cost of maintenance. For me personally, where do you even start?

by account-5

5/21/2025 at 1:03:10 PM

It grew organically so there was never a huge cost Really, except when we decided to build a building for The power plant because it was getting out of hand. It’s been a few thousand dollars a year in growth as we add batteries and panels. Also a bit of labor for installation of course, but we handle that in house.

by K0balt

5/21/2025 at 1:20:16 PM

> It grew organically so there was never a huge cost Really,

Ahh, the accounting style of hobby projects. I’m very familiar with this because I do it, too.

Nothing ever feels expensive if you just never add it all up and value your time at $0 because it’s fun.

by Aurornis

5/21/2025 at 1:40:20 PM

The total cost of the system so far is about $87k, and operating cost is around 4000 a year (includes equipment amortisation, slow expansion, direct operating costs). In all, for several homes, and a farm it’s very affordable. Getting power hooked up to a single house from the utilities is about $9000, so our buildout is roughly 2x what we might have spent just to get hooked up to the grid.

We do buy carefully, and all the engineering is done by me. We have employees on the farm so much of the labor of installing underground cable etc was “free” (lol).

Still, we are miles ahead of our costs if we were hooked up to the grid (which also would have cost us an additional $20k just for poles to get close, and we still would have had to bury the cables on campus along with the water and data, if we didn’t want ugly poles all over, so that part is a wash)

I spend about 4 hours a week on utilities based projects, mostly engineering monitoring and control systems so that I spend less time working on the utilities. (So, futzing around with electronics because I have an excuse to) it feels like meaningful work that I care about, so that’s nice.

by K0balt

5/21/2025 at 6:18:17 PM

That sounds incredible. This is the first year I've really started digging deep into solar generation and battery storage and it's one big fascinating rabbit hole.

I've looked at it from a bunch of different angles and keep coming to the conclusion that for rural and suburban areas with the space for panels, off-grid solar is the future.

by bityard

5/21/2025 at 3:12:58 PM

Thank you so much for these posts! It makes me very optimistic about the future.

For the longest time we all watched from the sidelines, hoping that the desire to turn off coal-fired power plants, and research often funded by tax dollars, would get the ball moving on solar. Now that the market has its magic invisible hand on that ball, it seems clear to me we have a path out of this mess.

Rant your stupid “drill baby drill” crap all you want magats, we are going to solar, wind, and fusion our way to a better world, and there is nothing you can do to stop us.

by BubbleRings

5/21/2025 at 4:45:15 PM

That’s silly, why make it political? If anything the political encroachment came from the green crowd first, cafe standards, EV mandates and the like.

The best way forward has always been to explore all energy avenues, and that will include fossil fuels as well. At least you’ve included nuclear, but left out fission, strangely, which is the best hope of electric generation replacement we currently have.

I’m tired of this team blue for electric (except Tesla now, lol) and team red for oil. They are choices with trade offs, and are friends, not enemies.

by strawhatguy

5/21/2025 at 6:31:44 PM

No offence, but everything is political. Much of our lives are controlled by laws. These laws are all politically controlled. To say it's silly to make something political, usually suggests your supported political slant is difficult to justify. Trade offs are only possible when the party in charge is willing to work with EVERYONE, we don't have that now. Thus the criticism.

by bloomingeek

5/23/2025 at 4:50:53 PM

Politics works through division by way of laws. Reduce the laws, reduce the division, and therefore politics.

by strawhatguy

5/22/2025 at 12:43:47 PM

Politics is simply preference.

by mensetmanusman

5/21/2025 at 4:08:35 PM

Fission first! Let's build more nuclear power plants too. We know how to do it, and it's only so expensive because we got scared and stopped. Economies of scale for clean, safe, reliable baseload power.

by aftbit

5/21/2025 at 8:06:19 PM

Turns out, I'm already on fission.

What I've done is tap into an existing fission reactor. It's some distance from my house, but there's a lot of excess energy there leaking out. I put up some collectors to capture it.

Was really quite cheap to do, and I don't have to pay anyone to actually run the reactor.

by bruce511

5/21/2025 at 11:53:14 PM

It's mostly a fusion reactor, to be pedantic.

by dgacmu

5/22/2025 at 1:56:17 AM

rats... I meant fusion :) There's me getting my nuclears all mixed up...

by bruce511

5/21/2025 at 10:15:40 PM

Greens here in Europe often complain about nuclear reactors and I just don't have the heart to tell them.

by tmtvl

5/21/2025 at 3:08:23 PM

> and value your time at $0 because it’s fun.

I don't know if you were being ironic or not but... that's an absolute truth. Our free time doesn't have a fixed rate. It doesn't have a rate at all. What you do during free time can be basically seen as either:

* a chore you don't like to do

* something you like to do.

Any task can swing between those states depending on your mood. If installing your own solar plant or self-host your server rack (as OP is doing) is something you enjoy doing, then yes, it costs exactly $0 in labor.

by darkwater

5/21/2025 at 4:04:24 PM

Agreed. I get asked to repair electronics for people quite often and I charge drastically differently for labor depending on whether I will enjoy the job or not.

by thedanbob

5/21/2025 at 1:20:05 PM

How much are you valuing your own time? Theres money cost, then theres time cost and the final one is in more remote communities with cold weather… insurance costs on failure…

Also to be clear - good on you for building out rural off grid electrical. Its a fun project and satisfying no doubt (outaide of costa)

by boringg

5/21/2025 at 1:53:33 PM

I don’t know the OP’s situation but I’ve seen that many coffee growers have to do this because in high altitude tropical areas there is simply no one who will do the work anyway. They also have a very different regulatory structure in practice to what we have in the continental US and Europe.

I’ve spoken to people from Rural Georgia (which is about an hour from Atlanta depending on the direction you’re driving) in Microcenter that are usually there to wire up their farm or factory with sufficient network capacity to keep production rolling. They have mentioned that they have had to do their own trenching for last mile for various services. Sometimes that means they literally drive down to Herc rentals, pick up a trenching machine, and do it themselves since the wait for someone else to do it is months away and that’s a long time if your business needs internet, water, power, etc.

by Moto7451

5/22/2025 at 10:39:45 AM

It’s been an adventure, but it would be disingenuous to imply that a don’t enjoy the challenge. It is very satisfying to have your work be so useful to many people. As for failure, we have them sometimes, but our casualty downtime for the last 6 years is <15 minutes. We have a highly redundant system that can run on as few as 2 of the 6 inverters, 8 separate battery banks, 16 separate panel banks with 9 separate charge controllers, 2 generators, and a completely separate redundant inverter for emergency power, as well as a separate power reserve system for control and monitoring power.

by K0balt

5/21/2025 at 4:18:25 PM

reminds me of that Hunter S. Thompson quote from Fear and Loathing in Las Vegas, "Not that we needed all that for the trip, but once you get locked into a serious [solar power setup], the tendency is to push it as far as you can.”"

by jhfdbkofdchk

5/22/2025 at 2:36:29 AM

Lol. Definitely!

It’s a ratchet:

Need more power: Buy more panels, they are cheap! Need more power: Buy more panels, they are cheap! Need more power: Buy more panels, they are cheap! Need more power: Can’t buy more panels, need more batteries to stabilize the system. Thankfully , batteries are getting better and cheaper! Lots of power, so much we need to find new ways to benefit from it! Need more power: Buy more panels, they are cheap! ……

The economics of panels are basically 20 percent APR here over 20 years. Over 40 years it drops to around 10 percent for out of service life panels.

by K0balt

5/21/2025 at 2:35:28 PM

What's your farm? How can someone reach out to buy small amounts of coffee from you, say 2-3 70kg bags?

by roflyear

5/21/2025 at 3:14:37 PM

Where will the drop be?

by sgt

5/21/2025 at 9:32:56 PM

You mean roaster? ceto.coffee

by roflyear

5/21/2025 at 12:55:18 PM

Would love a write up or links to resources for water extraction and treatment if you’d oblige.

by jedahan

5/21/2025 at 1:29:45 PM

I don’t have much in the way of links, but I can give you an overview.

We have a fair bit of vertical scale in the terrain here. We extract our water from a shallow well in a natural crevasse between ridges. It is made of concrete blocks stacked in a circle, filled with gravel and pinned with heavy rebar. The above ground part is finished in a regular fashion, with the blocks filled with concrete and a concrete cap. The well is built of a circle of 12 blocks, and is about 16 feet deep- where we encountered hard bedrock. An underground stream flows over this bedrock, which we extract from.

This raw water is pumped to a 300 gallon manifold tank about 160 feet above the extraction point using a 1HP centrifugal pump. From there, it flows down to the processing facility, where it is sediment and carbon filtered before flowing into either the 2600 gallon cistern, or back up the hill a bit to a 450 gallon upper campus distribution tank. Water passing through the processing facility is filtered and chlorinated, with the exception of the upper campus water, which is only filtered.

The upper campus water flows to cabins in the upper campus, and also serves as the input water for the RO system. The RO source water is pressurised by another centrifugal pump to 70psi, and is fed through a pair of 150GPD membranes after being filtered to 1 micron and passed through another carbon block. We run a 4:1 “waste” ratio to give us good life on the membranes (typically a year). The mineral rich “brine” flows into the 2600 gallon cistern and is used in the regular water.

We warehouse the drinking water in a 500-gallon tank at the processing facility.

There is a dual distribution system for water on campus. From the cistern at the processing facility RO water and regular water flows through underground tubing to a network of 5 utility huts where it is distributed to various homes and outbuildings. Each building then passes the main water through another carbon block to catch chemicals and chlorine, and drinking water gets mineralization and carbon again at the point of use.

The underground distribution network also carries 3 phase power, HVDC for solar, separate fiber optic networks for security, control, intranet, and ISP, as well as cat6 cables for RS485 control subsystems. The tank levels, pump controls, power distribution and usage monitoring, emergency and automatic casualty control shutoffs, etc are all operated over rs485 and modbusTCP to a server. It’s a lot of off the shelf stuff and some custom stuff that i have built. Someday I need to do a write up on that lol.

Anyway, that’s the view from space.

by K0balt

5/21/2025 at 3:58:45 PM

This is cool as hell. Sounds like you keep pretty busy, but if you ever had the inclination to write more about it or post some pictures somewhere, I for one would love to see.

by el_benhameen

5/22/2025 at 1:19:04 PM

Thank you for the encouragement. It’s on my bucket list.

by K0balt

5/22/2025 at 1:43:27 PM

There is a few more details, especially of the early days, on my extremely neglected and out of date blog https://vivavistadelmar.wordpress.com/blog/

Also, yeah, I know. Wordpress wasn’t a great choice even years ago when I set up the blog, but I was going to self host as a static site “soon” anyway and I needed to get started… almost good enough is the mortal enemy of adequate.

by K0balt

5/21/2025 at 5:15:17 PM

Very interesting. I'm looking to do something very similar on a farm.

Would you mind sharing some more design details?

Questions that come to mind: What products are you using? Are you doing any AC-coupling between inverters? If not, are you just running your PV wires between buildings? Are you stepping up your AC voltages to 480v or so to cover greater distances with less loss? Thanks!

by networkisfine

5/22/2025 at 2:57:20 PM

Running the inverters in parallel synchronized in a three phase configuration, 2 per phase, 224/130. Since the power plant is centrally located, our longest run is about 270m. It’s at the edge of what we can do with the cable we have buried, so if we need to extend or add significantly more capacity we will probably go up to 440v for that segment, with a substation at the PED4 utility hut. Better efficiency in step up/step down is one of the reasons we chose 3 phase power.

The panels are mostly centralized with each string being a home-run to the power plant but we are building out an additional 10KW on a rooftop about 200 yards away, so that will be 600VDC buried cable.

We are testing small ( panel-back attached )grid-tie inverters for supplemental power at point of use, but we will see how much we can add before it results in stability issues. It would be great to be able to put a panel or two wherever it’s handy and just tie each panel separately into the ac distribution.

by K0balt

5/21/2025 at 5:28:39 PM

Naive question, why run inverters?

Wouldn't it be more efficient to run direct DC appliances?

We have a building on our farm without power and it'd be ideal to be able to charge batteries and run lights at night

It seems to me that we would have to upsize batteries in order to make up for the loss in converting to AC

by arwineap

5/21/2025 at 5:32:14 PM

> Dumb question, why run inverters?

Can't say for OP, but DC appliances are just difficult to find, usually more expensive due to economies of scale and not as uniform in voltage (12/24/48V) as AC appliances. If your battery is in a shed somewhere it's also much easier to run a smaller gauge AC wire than setup distribution for your DC power.

Most large system are also 48V so you need to get it down to 12/24V which adds components anyway, at which point you might as well just have an inverter and not worry about any of that.

by belval

5/21/2025 at 8:01:02 PM

You also need some sort of battery management, and inverters typically have this built in as well.

So yeah, you can get by without an inverter, but then you need a battery charger manager so as not to overcharge, and (depending on the battery chemistry) something to cut off the battery as it runs down. (Lead acid for example shouldn't go below 50%).

by bruce511

5/22/2025 at 2:39:23 PM

As a parallel answer, for small systems this can make sense, although in anything larger than a single small cabin or small boat it probably is borderline these days. Modern inverters are quite efficient, and DC distribution carries a lot of issues, and gets downright dangerous at higher voltages necessary for large appliances.

20 years or so ago I rebuilt a 60’ schooner, and even on that scale AC was by far the best choice. Just the wiring for a DC system was more expensive then double Refund inverters, and most of the appliances were actually less efficient, since they had their own inverters inside them (DC-DC converters). In all there just wasn’t any justification, and corrosion is another issue on boats, so we went all AC.

by K0balt

5/22/2025 at 2:41:58 AM

To be clear, we are distributing power over about 600m of length, so it has to be high voltage. HVDC is very very dangerous, I would not want it in my house. Not only that, it’s hard to find things that are efficient and work on high voltage DC. Since our batteries are already 60V, our inverters already are very efficient, it’s simply not worth it. Panels are so cheap, it almost doesn’t matter how you are trying to save power, the answer is that it’s almost always cheaper just to buy more panels.

by K0balt

5/21/2025 at 5:41:03 PM

Not who you're asking.

I really don't see why we're still using A/C inside our houses / apartments. I understand that the transmission loss is lower when sending A/C, so it makes sense, but then nearly every device in my house has their own AC to DC converter. Just have one AC-DC converter per building.

I'd like the future to just be USB-C sockets in my house. We have USB-C PD 3.1 which supports up to 48v, I imagine that would be good for all devices.

There are probably safety reasons why this future might be difficult.

by vhanda

5/21/2025 at 6:14:02 PM

That would have been a good argument to make a decade or two ago but these days switch-mode power supplies are very efficient, and GaN ones even more so.

I have a small mess of 12-ish volt computer/network equipment in the corner of my office and looked into running it all off of one $40 high-amp power supply to eliminate all the wall warts and bricks. By the time I figured out power distribution and termination, buck/boost converters for the things that aren't 12V, it all seemed like a lot of work compared to just spending a couple hours tidying up the cabling and hiding the wall warts.

You can live in the future now and install power outlets with USB-PD built right in, although a quick glance suggests they top out at 65W. Fine for phones and tablets, might not keep a gaming laptop charged while in use.

by bityard

5/23/2025 at 5:18:25 AM

At USB voltages, one or two volts of drop is significant. You need very heavy cables, and for every voltage USB-PD allows you'd need another set of cables.

Also, some devices run directly on AC, or need more than USB can do, even with EPR. Since we already need AC for that, why add more wires when USB chargers are cheap and efficient and reliable these days?

by eternityforest

5/22/2025 at 1:25:58 PM

A lot of appliances need >1kw.

This requires higher voltage and robust connectors.

That level of DC is quite dangerous compared to AC for many reasons.

Also, unless you want to have 60lb extension cords the size of bratwurst, you need to go high voltage. High voltage DC is its own kind of devil, and is something I would not want in my household except in very isolated, self contained places.

High voltage, high current DC is on yet another level of mortal threat, able to do cool tricks like making extensions cords burn from one end to the other like cartoon dynamite fuses. Also, absolutely the best for accidental electrocution, severe burns and flash blindness, and setting otherwise fire resistant structures thoroughly aflame.

by K0balt

5/22/2025 at 5:42:51 PM

I'm not an electrical specialist but there are three major reasons I'm aware of that AC "won" at normal household/commercial power levels:

1. Switching. If you go look at your favorite part supplier you can find a bunch of switches that are rated to switch 250 volts AC and pass 16 amps, enough for basically any standard household outlet anywhere in the world. Those same switches are only rated for 24 volts DC. Why? Because of arcing. AC voltage passes through zero twice a cycle, which means that any arc that may be formed will self-extinguish within a hundredth of a second. DC doesn't do that, so the arc potential has to be limited either by reducing the voltage or increasing the size/complexity/cost of the switch/relay/contactor itself. This also applies to any connectors that may be unplugged under power like wall outlets. If you want to do the same amount of work with DC as you do with AC you basically get the choice between doing it at lower voltage with thick expensive wires or doing it at higher voltage with expensive switches, relays, outlets, etc.

2. Motors. Synchronous AC motors are EVERYWHERE. They're simple, cheap, efficient, and as long as they're not overloaded they run at a consistent speed determined by the number of magnetic poles in the motor and the AC frequency. If you have an appliance or power tool that runs on mains power and does not offer motor speed control (or only offers two or three speed settings) it's likely one of these. Native DC motors are also cheap and simple but but have very different performance characteristics, no native mechanism for precise speed control, and flow current through the rotor which requires brushed contacts that wear out over time. "Brushless DC" motors are actually AC motors paired with a controller which is more or less a DC->AC inverter, adding cost and complexity that may not be otherwise necessary or beneficial to the application.

3. Voltage conversion. AC can use simple wound transformers to efficiently trade voltage for current or vice versa using nothing but wire and metal. You might have used or even built one in a middle-school era science class. DC voltage conversion on the other hand, the simple methods are inefficient and the efficient methods require high-frequency electronics which only became inexpensive enough to go mainstream in the last 50ish years.

None of these are insurmountable problems of course, especially these days when switch-mode power supplies, inverters, VFDs, etc. are cheaper than ever but they still make things more complicated and require going against in some cases multiple lifetimes of industry inertia to purchase equipment produced in much lower volumes which means higher costs, and especially for home applications where size and weight are not the biggest deals it can often be easier/cheaper to just run a larger solar/battery setup to counteract the efficiency losses.

In the RV and boat worlds where size and weight matter you'll find a lot more DC appliances, but those are also generally smaller capacity than a household equivalent.

by wolrah

5/21/2025 at 1:52:08 PM

Where in the Caribbean?

by pryelluw

5/21/2025 at 9:28:01 PM

This sounds awesome!

Do you have a tech blog or writeup on what things you used, what parts broke down, or what kind of things needed to be fixed over time?

by h4ck_th3_pl4n3t

5/22/2025 at 6:58:01 AM

That sounds like a dream gig. Do you find it satisfying running your own utility?

by abraae

5/22/2025 at 1:20:52 PM

It is enormously satisfying to be doing something that is so useful to people close to you. I just wish I could focus more on that instead of other projects, but c’est la vie.

by K0balt

5/22/2025 at 4:57:21 AM

> It’s strange to me that people in rural areas pay for electricity. It makes no economic sense, at least here in the Caribbean.

When I took a vacation to Aruba, I was very disappointed to see very limited solar and EV adoption. Public transportation (buses) were running on gas, as were most personal vehicles.

It was nuts to me considering there was only 1 overcast day out of the 7 I was there, and you definitely don't need any energy for heating, ever.

by antisthenes

5/21/2025 at 9:03:38 AM

I have a solar system in my house in london. 5kw, 13kwhr battery. I am self sufficient from end of march to october.

I recently got a second hand electric car. I bought an EV plug (total fucking ripoff. its a fucking plug with a contactor, RCD and a CAN interface. no way is that worth fucking £600)

It has some basic control to allow me to charge from excess solar. What is not easy to do is charge at night without draining the house battery. Its fine for me, because I have Home Assistant, with enough fiddling I can get all the systems to talk to each other to play ball. (to add to the complication, I'm on a variable rate tariff, so price can be negative or £1 a kwhr)

I would really love a "house power API" that would allow a "controller" to locally control the power behavior of all the things in a house. Because at the moment, a "normal" person wouldn't be able to charge their car and have house batteries and have solar, and optimise for cost.

by KaiserPro

5/21/2025 at 2:22:17 PM

Would be interesting to know how London compare to Sweden. Electricity here are generally about twice to four times more expensive during the winter than during the summer, and energy consumption is about twice the amount during winter compared to summer. On average people here spend around 75% of the total energy bill during winter.

by belorn

5/22/2025 at 7:15:03 AM

Generally people are on fixed rates that are updated yearly. Its pretty "new" to get variable rates here.

https://agilebuddy.uk/historic/agile

has some historic prices. We still use gas for heating, so there isn't so much seasonality for consumption. (there is, but not in the same way).

What does affect price is wind. you can see in december there were both record high prices and record low. The more wind we have the cheap power becomes. so in winter its generally quite cheap, but then also it can flip and become very expensive, because gas imports are expensive.

by KaiserPro

5/21/2025 at 9:15:51 AM

If your electrical installation allows it: You can connect your ev plug before the battery so that it does not drain the battery. You can do this by placing the fuse/connection before the measurement clamps for the battery. Somewhere in between your mains connection and your battery/solar system.

This way the battery does not see the load and does not provide power to your EV.

That way you can still use excess solar (before you inject it into the mains) to charge your car + you do not pull power from your battery :)

by epiecs

5/21/2025 at 10:24:28 AM

The ideal solution is for the battery to have a third set of clamps to measure the EV. But as I don't have installer access to the software (centrally managed for the win) I'm not sure thats possible.

I might ask to see if thats possible. I probably need more panels to cover the winter load.

by KaiserPro

5/21/2025 at 10:53:18 AM

> no way is that worth fucking £600)

Liability coverage, and UL certification (or UK/EU equivalent), for the company is. Though see perhaps:

* https://en.wikipedia.org/wiki/OpenEVSE

> I would really love a "house power API" that would allow a "controller" to locally control the power behavior of all the things in a house.

With regards to EV and the grid, see perhaps:

* https://en.wikipedia.org/wiki/ISO_15118

* Also: https://www.ampcontrol.io/post/what-are-ocpp-iec-63110-iso-1...

For an (industrial) electrical communication protocol, perhaps:

* https://en.wikipedia.org/wiki/IEC_61850

by throw0101b

5/21/2025 at 9:17:11 AM

Midnight Solar are the OG company in off grid and they have a "waste not" feature from way back that triggers any device when the parameters you set are reached, ie: float voltage, and/or other things, like a second set point where power would be sent to a third load, like the grid or water heating. https://www.midnitesolar.com/ hard core techies, even had the pleasure of detailing my inadvertant and unsucessfull attempts to melt one of there controlers.......literaly had a main lug get loose, and the panels arc melted the lug to slag, and it lived. in any case, there web site has a wealth of info on what is possible, and to look for elsewhere

by metalman

5/21/2025 at 2:35:02 PM

Midnite Classics are great... But the web APIs seem to be deprecated. Do you know of any tools that can get data off them?

by _whiteCaps_

5/21/2025 at 11:24:30 PM

nothing other than what is published in the manuals, there is a link to a third party software for monitoring the clasics, but if you want the inside story, call them....they answer the phone and speak many dialects of techinese there latest offering is a game changer "the 1" it does everything 11kw of 600 volt solar in, to any kind of 48 volt battery, and grid tie, and single,split phase and 3 phase 208 volt ac out, one box 98 lbs, 5k list you can install 200 % extra solar for low light, or norther locations specs are wild https://www.midnitesolar.com/productPhoto.php?product_ID=766...

by metalman

5/21/2025 at 12:21:13 PM

We have https://www.myenergi.com/ for our car charger and it seems to be able to integrate batteries, charging and panels like you suggest, only you have to go all in. We have parts of it and are tempted to use more, but the lock-in angle is a bit off-putting

by bencyoung

5/21/2025 at 1:39:42 PM

Yeah I have a Zappi, but as you know its got no local API, and it doesn't like getting warm. However it _cant_ control my battery directly, because its made by tesla. (I mean thats also my fault....)

I have also heard that if you go all in it works much better. It does have the nice feature of diverting to other devices instead of the grid, and giving priority to certain devices.

by KaiserPro

5/21/2025 at 4:06:08 PM

If your rates can go negative you should be charging the car and house batteries at that time if possible and then selling back to the grid at peak times. Does your home assistant get real-time rate data and can it facilitate that?

by SoftTalker

5/21/2025 at 12:11:09 PM

I mean, it's a bit more than a contactor and an RCD, it also has PEN fault detection because TN-C-S is how most of us are wired up to the grid.

Then for use with smart tariffs like IOG there's a microcontroller, cloud gateway for them to hook into for OCCP to turn on and off the charger when the grid is cheapest/greenest etc.

So £600 is about right, once you add in R&D, certification, profit margin, warranty claim % etc.

by philjohn

5/21/2025 at 1:41:15 PM

> Then for use with smart tariffs

I wish it had all of that. I would actually pay for that. The Zappi from myenergi promises much but fails to deliver.

by KaiserPro

5/21/2025 at 6:15:35 PM

That's odd - I've got the Zappi and it works perfectly with Intelligent Octopus Go. Plug the car in, have a HomeAssistant automation that detects this and sets the "charge to add" on Octopus and enjoy the car being charged the next morning.

I always recommend hardwiring it though, rather than relying on Wifi through a brick wall.

by philjohn

5/21/2025 at 4:47:12 PM

[dead]

by hkgjjgjfjfjfjf

5/21/2025 at 4:00:41 PM

It's kind of telling/ironic that the author gripes (whether rightfully or wrongly) about PG&E wanting more return on investment due to their risk of doing business in California, but when the author decides to build their own power system to not deal with PG&E, literally almost every paragraph related to their planning/setup contains a mention of some different California/city regulation that the author had to meet or else it's illegal for them to build their own power system. To the point where they had to pay a professional to help them meet all the regulations.

by thegrim33

5/21/2025 at 5:37:10 PM

This is the key issue. We are over-regulated.

We rebuilt our house in the SF Bay Area in 2022 and went fully electric, no gas line anymore. It was really sad that I couldn't resuse any of my previous 12 kwh solar panels that were fully functioning and had another 10-15 years on them as they wouldn't match the new regulations.

I tried to get them installed on a separate area in my own backyard for off-the-grid charger just for my car, but you are not allowed to have a big off-the-grid system unconnected to PG&E. No electrician was willing to help with risk of losing license. The author was lucky that his dad could help with electrical.

Due to similar issues, I couldn't find anyone to take them for free as well. Demo dad was a truly sad day to watch these perfectly functioning solar panels being destroyed by a crane.

by vasusen

5/21/2025 at 6:26:27 PM

Wow, not being able to have an off-grid system AT ALL without the utility's approval just sounds bonkers to me. I guess PG&E is even more evil than I thought.

Used solar panels are a pretty brisk business right now. Lots of places are replacing their 10-15 year-old panels with new ones just due to the better efficiency and capacity alone. And now that we have over a decade of large-scale solar experience to draw from, we are finding that they tend to degrade a lot slower than expected and that the original 30-year lifespan was highly conservative. I'm surprised you couldn't find someone from out of state to buy them.

by bityard

5/21/2025 at 10:32:30 PM

I was reading something the other day about an interesting dichotomy in California. It’s one of the most heavily regulated states, yet also one of the most lawless at the same time.

by vondur

5/21/2025 at 8:23:24 AM

I did build my own solar system too. In Switzerland.

Took me 1-2 month planning and then 3 month building it alone nearly each day. Sept 2023 til Xmas 2023. Got all the hardware from a PV dealer friend on his purchase price level. Even 24 panels I have put myself alone onto the roof. With two persons it was a bit better.

I've got: 420w x 71 Trina solar panels and two SolarEdge inverters. SE10K Hybrid and a SE17k. Also a 24kWh BYD LFP battery.

All prices without state funding: Offers from local installers for 56*410W Panels without battery were around 65k CHF.

I've paid now 44k CHF including every kind of cost associated with building it.

Should write a blog post about it :-)

Next project is a solar fence with 6kWp.

by cyri

5/21/2025 at 8:40:47 AM

What do you do with that much electricity? Was it necessary to over-dimension for winter?

by pingou

5/21/2025 at 9:43:19 AM

Of course it is a bit oversized.

We’re living in a big river valley where we have fog from October until March. On some days in November the fog is so dense that the whole system does not produce any kind of energy. On the other days the produced kWh are enough to charge the battery.

We have a heat pump (extrem efficient), servers, one electric car, etc which consumes all together around 13MWh per year. The solar system produces around 27.5MWh. Most of the energy gets fed back into the grid.

We’re currently investigating to connect the neighbour houses physically to us. But that takes even more time here :-(

by cyri

5/21/2025 at 10:07:01 AM

FYI: Neighborhood-level connections are changing starting next January (look up RCP and CEL).

by amenghra

5/21/2025 at 9:16:24 AM

I would also be interested in the reasoning here!

Just for comparisons sake, our 8.6kwP setup with a 10kwH battery cost us (after subsidies from governemnt) appr. ~€11.5k. Haven't received all the subsidies yet, so the total will be lower by about 1.5k (I think). Everything was done through installers, we didn't lift a finger (also couldn't, because when it comes to electricity I have as much experience as the dog next door).

If I had more due diligence before I would have scaled up the panels up to at least 10kwP, for future proofing probably to 12kwP. This is mostly just to make sure winter is covered better, as our production is really low as we have a 10° flat roof installation.

by raphael_l

5/21/2025 at 9:12:21 AM

If you have an EV that can be charged only at night, a big battery is required.

by yvan

5/21/2025 at 9:45:43 AM

For solar excess charging I use evcc.io

When I charge the car via battery then only down to ~75% for now. The remaining energy is needed by the house during winter months.

by cyri

5/21/2025 at 12:11:16 PM

How much did you pay for the panels, and what's your capacity factor? (Kilowatt hours produced on average per nominal peak kilowatt.)

by kragen

5/21/2025 at 7:51:44 AM

> I found three companies and gave them my PG&E usage for the past year (about 16,000 kwh) and got three quotes ranging from ~45 — 55k.

Wow these rates are crazy. A 10kW setup costs you maybe €10.000 all-in here in the Netherlands.

What's going on with these rates? Do they already include the ridiculous tarrifs?

A new battery setup for a 20kWh LFP battery + 10 kW inverter + installation is €7000 now.

And dropping, fast.

Assuming batteries and PV come from China, someone in California is making a lot of money or the government is straining the process with bureaucracy costing $30.000 per setup.

by apexalpha

5/21/2025 at 8:47:56 AM

Batteries are dropping fast in price, but for the USA, they might be going up because of tariffs. Neatly sidestepping that:

I have a powerwall 2 with 5kw panels, which I've had since about 2021. At the time it was the biggest, cheapest, had a grid isolation mode, and could be mounted outside. (I didn't trust tesla back then, and I sure as shit don't now. Moreover, once it catches fire, that shit aint going out anytime soon)

It still cost about £7k installed.

From about march/april to end of october, we are power sufficient (london, even with rainy days, gas hot water though.)

If I were to get a new system, 13kwhr of battery is something like £2k, plus inverter/charger.

The panels are dirt cheap, to the point where the scaffolding costs more than the panels. (and the mounts.)

by KaiserPro

5/21/2025 at 11:05:19 AM

In USA, as a general off the cuff that may be wrong, DIY prices is generally ~1/3 of contractor price.

A $45k quote would correspond roughly to 14k euro of materials.

by ty6853

5/21/2025 at 3:14:36 PM

Similarly in Australia I recently paid about $10k AUD (after subsidies) for 13kw of panels and a 10kw inverter.

New subsidies this year for batteries mean I can get a 15kwh battery installed for around 2-3k AUD

by dbetteridge

5/21/2025 at 8:22:44 AM

Crazy stuff. Ten years ago I paid £5.5k GBP for a 3.7kW system. Since then I would expect the labour component to have gone up but the panels to have come down. I guess the skilled labour shortage in the US is having a very real effect on prices.

Under the subsidy rules for feed-in-tariffs at the time, that had to be done with an MCS approved installer. All work in England would require an approved "Part P" signoff anyway. However it did not require council planning approva, nor grid approval for that size of system.

by pjc50

5/21/2025 at 1:00:37 PM

There's not a shortage of skilled labor so much in US as there is a shortage of people able to go through the racketeering process of getting a contractor license, which also requires being a half-slave to someone with a license for a number of years. It's straight up mercantilist style shake-down to benefit prior entrants. It is easier in US to become an electrical engineer than it is to become a guy who adds a new outlet to a room addition, but that has nothing to do with skill.

In fact when I was first hired as an engineer, it was actually someone that wanted an electrician but hired EEs instead because they are cheaper and more readily available.

One of the worst is something like installing HVAC stuff. I got an EPA refrigerant license in 2 days of studying and then did my own myself. If I wanted to install it for a profit for someone else, I would have to spend 4 years working for someone else with a license first to get the contractor license! The end result is it legitimately cost like $700 to have a single capacitor replaced on an air conditioner, and in places like Florida if you do it for someone else without years of 'training' you're now a felon.

by ty6853

5/21/2025 at 6:49:35 PM

I always found solar farm engineering intensely interesting and looked seriously into becoming an electrician as a second career as something to "retire into" once I got sick of working in tech. And like you say, it turns out it's not something you can just make a lateral move into, no matter how quickly you can learn and how hard you're willing to study. "Becoming an electrician" is a young person's game.

by bityard

5/21/2025 at 9:53:24 PM

There are a few places where you can work as an electrician without a license. Might be the same bumfuck places where solar or wind farms are. I think most of them are in the midwest or plain states.

Where I live you can't but go figure you can become a licensed finish carpenter with a simple test.

One loophole I looked I might look into some day is moving to another state with the least requirements for a license, then getting it, then transferring it to another state, which is allowed at least here.

by ty6853

5/21/2025 at 8:42:36 AM

I see 7k€ for 12kWp, retail, for a diy ground install set for our summer house. That's before 4k€ in subsidies. No net metering, and feedin compensation is capped at 0.02€/kWh. But at 3k€ net, who cares? Even with the low electricity rates here, this makes sense. Even for a summer house!

by markvdb

5/21/2025 at 3:30:57 PM

In my town in NY state USA, they require a stamped engineering drawing for a ground mount system and it has to be rated for wind and snow load. Most of the ground mounts which come with stamped drawings have run about $1/W total cost which will meet my local needs for a set of panels in the 5kW to 20kW size range. This cost includes concrete, all support structure, and the racking that the panels attach to. This cost does not include panels, wiring, nor inverter.

If you're able to get a 12kW rated full system, including racking, panels, and inverter for the equivalent of $1/W that's an amazing deal! I wish prices here were like that.

by bradfa

5/21/2025 at 4:30:29 PM

I posted above about the price because when we've gotten quotes – and this is over a year back – they were really high! Not sure what the deal is because the graphs all show the cost of green electricity cratering; but somehow on the residential side of things here in the U.S – even in rural areas with very relaxed restrictions – it's super pricey!

by gdubs

5/21/2025 at 8:05:30 AM

For comparison, my 10 kW solar install completed last week cost 24k CAD (15k EUR). That's just panels, inverters and installation. The incremental cost was likely in part due to the ~160% tariffs on solar panels imposed by the Canadian government, but not all.

by slavik81

5/21/2025 at 1:25:07 PM

Ouch. My 7.8kW system fully installed was 13k CAD ( a bunch was DIY)

Had it for a year now. Generated 7.7kWh which is worth $950. Took out natural gas, power bill for the entire year (heat pump, elec hot water) was $1000.

Snowy mountain town in a tight valley in BC.

by testing22321

5/21/2025 at 7:58:38 AM

Prices were high even during the Biden administration.

Markups due to subsidies are a part of it.

by bdcravens

5/21/2025 at 3:14:43 PM

Costs are also high for solar installers in the US. It is a relatively dangerous job (on par with roofers) which makes health insurance premiums unaffordable. The permitting process is also quite onerous in a great many localities, involving multiple parties (your installer, the HOA, the city, the county, the power company) and multiple inspections. US installers also tend to provide generous warranty plans, 15 years parts and labor is typical, and have to make sure they have the capital to honor them. This is especially a problem as some solar hardware manufacturers have had some serious quality control issues, especially on the inverters, and have resulted in quite a lot more warranty work than was initially expected.

The other issue was just plain pent-up demand. Installers could charge what they wanted because there weren't enough of them to go around, even as everybody and their dog started their own installer business. Many of those businesses were poorly run and have since gone under, leaving the homeowners high and dry when the inverter craps out and they're told by every other installer that they will not work on someone else's install and also told by the inverter manufacturer that if they attempt to replace the hardware themselves it will result in their warranty being voided.

by jandrese

5/21/2025 at 8:16:37 AM

Subsidy causing high prices? You're going to have to explain that.

by pjc50

5/21/2025 at 8:33:23 AM

Customer is willing to pay 10k. Supplier will charge 10k.

Customer is willing to pay 10k, state is willing to pay 5k. Supplier will charge 15k.

by empiko

5/21/2025 at 9:52:37 AM

That applies with inelastic goods - land for example - where supply can't increase

Assuming the base cost is 8k

Supplier A and Supplier B charge 15k and have 100 customers between them, making 350k each

Supplier B decides to undercut Supplier A, and charge 14k, and get all the customers, making 600k profit

Customer might be willing to pay 10k, but if there's two identical quotes, one for 10k and one for 9k they'll go for the 9k

by ta1243

5/21/2025 at 10:30:11 AM

> Customer might be willing to pay 10k, but if there's two identical quotes, one for 10k and one for 9k they'll go for the 9k

But you see the point. There's a comfortable cushion where everyone can make more money off the taxpayer and have an easier time of it. Spend a bit of it on better marketing to elevate yourself and justify the higher price in people's minds.

by robertlagrant

5/21/2025 at 12:38:57 PM

Only if you believe that the invisible hand of the market doesn't work

by ta1243

5/21/2025 at 3:12:18 PM

I'm not sure government incentives allow the free market to do its work, then. Why would you think it would?

by robertlagrant

5/21/2025 at 4:32:35 PM

government incentives help to reduce the externalities

You seem to think that two companies selling product A will rather sell 50 for $10 per unit profit than 100 for $9 per unit profit because it's easier.

I mean, it's a view, sure.

by ta1243

5/22/2025 at 8:15:07 AM

It's not my view, though. I already said what I think is more likely to happen.

by robertlagrant

5/22/2025 at 8:28:40 PM

> You seem to think that two companies selling product A will rather sell 50 for $10 per unit profit than 100 for $9 per unit profit because it's easier.

If the numbers are closer, then that's exactly what happens.

Would you rather sell 50 units for $19 per unit or 100 for $10 per unit? Option 1 gives you way less overhead and headache with cheap-o customers.

by antisthenes

5/21/2025 at 8:24:30 AM

- Subsidy starts: prices drop.

- Greed kicks in because capitalism: prices rise again, maybe not back to pre-subsidy levels, but they rise.

- Subsidy gets axed: prices rise to above pre-subsidy levels.

(Note: I'm personally entirely pro "subsidize things you want more of". But that requires a stable, trustworthy government that plans on longer timescales.)

by isoprophlex

5/21/2025 at 8:33:56 AM

Sounds like a situation where there's not enough competition.

the Netherlands had a net-metering subsidiy + good competition + frictionless install and as a result we have 3,5 solar panels per person installed.

by apexalpha

5/21/2025 at 9:38:56 AM

Or price fixing.

by bdcravens

5/21/2025 at 10:02:36 AM

There are two more steps:

- Demand drops due to increased price to buyers.

- Prices drop so manufacturers can remain profitable.

by genericresponse

5/21/2025 at 10:31:14 AM

> Greed kicks in because capitalism

There were no greedy people before capitalism. Of that we can be sure.

by robertlagrant

5/21/2025 at 2:59:25 PM

The perpetual existence of greed is not a good enough reason to structure all of society around that singular trait.

by jagger27

5/21/2025 at 2:50:39 PM

Greed is a Bad attribute in basically every ethical system and religion throughout history.

Capitalism, on the contrary, rewards it. The best way to be under capitalism is greedy (sneakily so, if necessary).

So yes, it is uniquely new to have a value system that rewards greed.

by komali2

5/21/2025 at 3:06:41 PM

It doesn't reward greed, it rewards value. You could just as well say national borders reward invasions.

by robertlagrant

5/21/2025 at 3:20:12 PM

No, greed is a necessary component. Because under capitalism both parties don't execute the trade, rationally at least, unless both are greedily better off.

Without greed it goes from a positive sum system to a destructive system because you no longer have the parties being better off from the transaction. From a cursory standpoint that might be ok (the economy won't implode if some small fraction does this like a minority of commercial activity being charity functions) but you basically lose most the information conveyed in prices and cost causing complete loss of productive allocation and it is an economic implosion.

by ty6853

5/22/2025 at 8:14:00 AM

You're mischaracterising "not wanting to overpay" and "getting something you need in return for what you have in excess" as "greed".

It's a pointless conversation if you're willing to do that. You're just changing definitions before arguing them.

by robertlagrant

5/22/2025 at 1:18:39 PM

I will allow for sake of argument then trading for needs to be excepted. Under your definition it would also implode, just not fully destruct.

by ty6853

5/23/2025 at 9:03:51 AM

Trading for wants is no different to trading for needs from a capitalism perspective. It just removes the need for a central bureaucracy that decides what counts as a need.

by robertlagrant

5/21/2025 at 4:32:45 PM

Do note that nothing in this system incentivizes behaviour that creates societies that could last, say, several hundred years.

by isoprophlex

5/21/2025 at 8:49:11 AM

There was a study in France showing that for rent subsidies.[1]

In France, the state pays max(rate * rent, cap) for apartments for students, unemployed and poor workers. Usually people don't qualify for ratio of the rent, because it's way over the cap for the subsidy. To keep up with inflation, the state re-evaluate the cap of the subsidy almost every year.

A french economist showed that there was a correlation between the cap of the rent subsidy and the rental market prices for small apartments. Of course, correlation is not causation, it could just be that the rental market follows the inflation as much as the cap. But this correlation doesn't happen for bigger and more luxurious appartments. Her explanation is that your poor household is only ready to afford €100 per month, as an example, the subsidy cap is €500, so the rental market prices these apartments to €600 (= 100 + 500). When the state re-evaluate the cap to €550, the rental market goes up to €650. (= 100 + 150)

[1] https://www.insee.fr/fr/statistiques/fichier/1376573/es381-3...

by acatton

5/21/2025 at 9:57:47 AM

The key difference in the markets is that it takes a very long time to build more apartments and houses, especially in France. There also isn't an option to not have housing. (Low elasticity) That keeps the short term supply effectively static. Same amount of supply, increase in money spent, inflation.

In a market like solar, there is production of more solar systems. There are also multiple readily available substitutes. (e.g. on-grid power) The effect of the subsidy should drive increased volume from manufacturers, keeping net price stable.

by genericresponse

5/21/2025 at 10:01:59 AM

and now you know why america's GDP is so high

by deadfoxygrandpa

5/21/2025 at 2:47:14 PM

Wow, what a fantastic write-up—thanks for sharing this! I’m a San Jose homeowner (and PG&E sufferer) with a homelab that pulls over 1 kW, and I’ve been down the DIY solar rabbit hole for the past two weeks. Based on my research, I’m planning a roughly 9 kW Signature Solar setup:

20× 455 W Canadian Solar panels (~$173 ea)

1× GridBoss MID V2 (~$2 400)

1× FlexBoss 21 (~$2 400)

4× Eco-Worthy 48 V 100 Ah LiFePO₄ batteries (~$1 500 ea)

18 U server rack (~$500) — total hardware ~$14 760

My big hang-up has been the rooftop work, permitting and inspections—almost no one I call will touch a true DIY system. If anyone here in the Bay Area has recommendations for installers or back-of-house permit-whisperers who’ll partner on a non-Tesla/Sunrun job, I’d love to hear how you made it happen. Thanks again for the inspiring guide!

by breakds

5/21/2025 at 5:46:40 PM

Greenlancer will draw up code-compliant plans that you can submit to your local building permit agency, and they'll revise if anything needs it. It cost less than $400 last year. You've done enough research that they'll be able to easily take your project and turn it into something legal.

I recently did an Enphase system of a similar size to yours. It was fully DIY except for wiring the combiner and a roofing company to plug all the holes I drilled. Working with PG&E was truly an epic year-plus battle culminating in a CPUC complaint, but in the end it was really just a bunch of emails.

I don't have any installer recommendations, but it should be easy enough to find a local electrician, and I've found that they tend to know others in adjacent fields.

by sowbug

5/21/2025 at 7:07:46 PM

Thanks so much for sharing your story – hearing about your DIY Enphase install (and epic PG&E battle!) really gives me confidence. And the information you shared is extremely helpful for first-time DIYers like me.

by breakds

5/21/2025 at 4:43:47 PM

Crazy, where I live the payback on the hardware would take ~114,000 kWh (or 13) years at 24kWh per day, $0.13/kWh).

Where you live it’s only 24,000 kWh to pay off the hardware, or just under 3 years ($0.61/kWh). I’d definitely pull the trigger.

by quickthrowman

5/21/2025 at 8:43:54 AM

Great to see DIY early adopters getting great savings here. I think the bigger trend here is lower cost, commoditization, and it eventually becoming a no-brainer for people that have the opportunity/space to be running their own micro grids for cost reasons. The cost of what you need here is still quite high. But making things easier to plug together helps. And of course component cost is coming down.

For example, you can buy kits on amazon for powering your shed or boat and it's essentially a smaller version of what you would put on your house. No electricians needed. No permits required. Here in Germany you can buy balcony solar kits in the supermarket. They only deliver a few hundred watts of power but it's plug and play. And you can get a nice little subsidy to do that. Some of these kits only cost a couple of hundred euro.

I could see that eventually adding a microgrid to a building is not going to break the bank. Car batteries are much larger than what goes in a house and kwh prices are trending well below 100$/kwh now. Meaning it should not cost tens of thousands to get a couple of tens of kwh to store energy. Inverters shouldn't break the bank either. The going rate for solar panels is around 200$.

Mostly current prices for home setups are much higher than the component cost mainly due to regulations, labor cost, certifications, etc. If you go off grid, you can just DIY and you end up much closer to the component cost. But of course long term both component cost and other cost are coming down. With the exception of labor cost probably. Though the skills needed will become more common and you might be able to do a lot of work yourself.

by jillesvangurp

5/21/2025 at 6:47:28 AM

Having done some work around net zero policy I am increasingly convinced that this is the way forward, and indeed that this will be the way things are done normally maybe 10-20 years from now. The concept is called "distributed generation" and in UK each distribution network keeps an "embedded capacity register" which is basically all the distributed energy resources that are connected to the grid at distribution level (i.e. in the local area). Over here the national grid largely operates at or over capacity, which is a very serious problem for the immediate future, especially as more and more power is drained by compute-heavy infrastructure (data centers and such). Distributed generation is an attractive solution for households regardless of which angle you look at it from.

by alex-moon

5/21/2025 at 7:06:46 AM

Well problem in the UK is that in summer there is like a magnitude more power from PV then in winter.

by looofooo0

5/21/2025 at 12:13:19 PM

No, having more power isn't a problem for solar; unlike coal or nuclear, solar can curtail production instantly and without suffering wear and tear. The problem is that in the UK in the winter there is an order of magnitude less power from PV than in the summer.

by kragen

5/21/2025 at 3:04:13 PM

magnitude less power from PV than in the summer

magnitude more power from PV than in the winter

That is a tautology.

by looofooo0

5/21/2025 at 6:50:03 PM

However, the implied meaning is significant. This site is full of engineers who, if they're good, invest a lot of time into understanding the implied meaning of what's said.

by butshouldyou

5/23/2025 at 5:17:33 AM

There is no implied meaning, you cannot derive PV building intend from it.

by looofooo0

5/21/2025 at 8:00:36 AM

I personally feel there should be more allowance for small personal wind generators in sub-urban areas. That would offset a bit at least in winter for places like the UK. Not sure what the actual laws are, but I can assume councils wont be too happy about someone putting one up on their home.

by calgoo

5/21/2025 at 8:10:52 AM

Wind generators really scale with size though. Small ones rarely make sense

by detaro

5/21/2025 at 12:14:23 PM

If the objective is to reduce the number of hours you're not self-sufficient for a given battery size, or reduce the size of your expensive batteries, even a couple hundred watts could make sense.

https://www.amazon.com/NINILADY-Vertical-Generator-Controlle... is a 600-watt-peak wind generator, designed for 11m/s winds, for sale in the US for US$300, presumably much cheaper in countries that aren't descending into kleptocratic tyranny. (I talked to someone who recently bought something similar for US$60. I think it was a 300-watt turbine.) It's a vertical-axis type, less than a meter in diameter. No worries about annoying the neighbors, and it'll probably do a great job of keeping your fridge running most of the time when it's cloudy.

50¢ per peak watt would be a terrible, uncompetitive price if you were a utility company considering how to build a wind farm to sell power for profit. But, if you're a homeowner seeking energy self-sufficiency because your Public Utilities Commission is trying to throw you under the bus because of regulatory capture, it's pretty affordable.

by kragen

5/22/2025 at 1:41:10 PM

Correction: according to what I found in https://news.ycombinator.com/item?id=44056971, 50¢ per peak watt would not be a terrible, uncompetitive price if you were a utility company considering how to build a wind farm. In fact, it's significantly cheaper than the prices they actually pay for big windmills.

by kragen

5/21/2025 at 1:04:18 PM

The issue is the payback is not worth the hate from your neighbors and capital cost. at least solar panels are quiet.

by lazide

5/21/2025 at 5:20:56 PM

Hence "community energy" - you do it with your neighbours - this model has worked in Scotland before - https://www.resilience.org/stories/2019-07-16/rebel-cities-t... - here is one from earlier this year - https://www.thenational.scot/news/24993445.local-groups-bid-... - and recent changes in planning legislation mean we should be seeing more of these in England in the near future - https://communityenergyengland.org/pages/community-wind

by alex-moon

5/21/2025 at 10:35:52 PM

Community energy makes sense for 2,000,000-watt windmills like the ones in your first article, but not for a 600-watt rooftop windmill that's less than a meter across. The 2,000,000-watt windmill ought to cost less per watt, but it requires successfully coordinating the community to support it (cf. the note in your third link about a "de facto ban on new onshore wind projects" being lifted). And looking at https://www.canarymedia.com/articles/wind/chart-wind-turbine... it looks like over the period 02015 to 02022 the prices of big windmills consistently stayed in the range of 80¢ to 130¢ per peak watt, which is actually more than the 50¢ per peak watt of the mail-order Amazon rooftop windmill. (The rooftop windmill will probably enjoy significantly lower capacity factors, but it's clearly in the same ballpark.)

This was surprising to me, since I thought big windmills were much cheaper per watt, so I dug a bit further. The figures check out. The current https://www.bbc.com/news/articles/c80kv5d7lp7o says a £40 million (US$52 million) onshore Manx wind farm might have "up to 5 turbines", and thus up to 10 megawatts, putting the total project cost closer to US$5/Wp. https://www.eia.gov/analysis/studies/powerplants/capitalcost... from 02019 has a capital cost breakdown of a 200MW hypothetical wind project costing US$253 million, consisting of 71 2.8-MW windmills, totaling US$1265/kW (127¢/Wp). About 60% of that (80¢/Wp) is "WTG [windmill] procurement and supply". A 50MW hypothetical wind project in the next section comes in at 168¢/Wp, and a 400MW hypothetical offshore wind project in the next section is 438¢/Wp.

So it's not at all clear to me that community wind energy, or utility-scale wind energy in general, is even cheaper or more efficient than mail-order rooftop windmills. It might be more expensive!

by kragen

5/21/2025 at 1:30:01 PM

If you have a house, you aren't going to get hate from your neighbors for a tiny turbine like this; it may not be quite as silent as solar panels, but it's pretty quiet.

by kragen

5/21/2025 at 8:09:11 AM

I was under the impression that small wind generators at the scale of suburban backyards are really uneconomical and don't produce sufficient energy for anything of practical use.

by Teever

5/21/2025 at 12:14:19 PM

small wind turbines are also horrendously unreliable because of mechanical failure. Same logic as to why pickup trucks are generally more reliable than a smart car.

by eldaisfish

5/21/2025 at 9:44:21 AM

I wonder what studies may exist on this. Were they all funded by Big Wind?

by bbarnett

5/21/2025 at 10:12:45 AM

Laws of physics: maximum power that can be generated is proportional to the swept area of the blades. So it scales exponentially as blade length increases.

by teamonkey

5/21/2025 at 12:15:10 PM

The swept area of the blades scales quadratically with the blade length, not exponentially. Exponential scaling is f(x) = knˣ, not f(x) = kxⁿ.

The difference between quadratic scaling and exponential scaling is earth-shatteringly enormous; this is not some minor detail.

With quadratic scaling, if f(1) = 1 and f(2) = 4, then f(10) = 100.

With exponential scaling, if f(1) = 1 and f(2) = 4, then f(10) = 262144, a 2600× difference. And the difference gets bigger from there on out.

by kragen

5/21/2025 at 3:49:59 PM

Unfortunately I can no longer edit the post, but of course you’re right. Max generated power is proportional to (blade length)^2, therefore quadratic, not exponential.

by teamonkey

5/21/2025 at 11:17:12 PM

I assumed that meant that big windmills would be much cheaper per watt than small ones, but according to what I'm finding in https://news.ycombinator.com/item?id=44056971, that doesn't seem to be the case. Small rooftop windmills may actually be cheaper!

by kragen

5/23/2025 at 1:00:05 PM

There’s another limiting factor though, which is that power is also proportional to (wind speed)^3, and the wind is greater higher up.

Although having said that, I do believe the main reasons we don’t use them in the UK are noise and wildlife concerns. In many ways the total efficiency doesn’t matter if it’s generating enough power.

by teamonkey

5/23/2025 at 5:15:26 PM

Yes, so it's puzzling that the small windmills (necessarily designed for low wind speeds) cost less per peak watt. You'd think getting more power per square meter higher up would reduce the cost per peak watt. Wind speeds are more consistent up there, too.

The wildlife concerns are completely specious. The main reason you don't use them in the UK are that the wrong sort of people have political power.

by kragen

5/21/2025 at 8:35:31 AM

Uneconomical and the sort of thing that really annoys the neighbors. We only just got onshore wind unbanned entirely, and Reform are heavily against permitting renewables at all.

by pjc50

5/21/2025 at 9:33:59 AM

They barely produce anything at all. You really need a bigger one and putting it very high up for it to generate any real power.

by victorbjorklund

5/21/2025 at 6:53:48 PM

Every reply is talking about how wind doesn't make sense, how its uneconomical, or how its a nuisance. I can offer an opposing take:

My father has been using wind power in a semi-suburban area in the Uk for close to 20 years now. They have a large wind turbine now but had a much smaller one for a long time. Outside of cookie-cutter estates, there's sufficient tree and building cover that its barely visible to the neighbors. It provides most of their home power.

by butshouldyou

5/21/2025 at 10:04:06 AM

Eventually it'll become noisy, yet provide little value.

by sgt

5/21/2025 at 3:23:51 PM

Love to see housing developments, rather than just adding an overbearing HOA, would instead consider neighborhood power grids (and perhaps a collective ISP while we're wishing for things).

by JKCalhoun

5/21/2025 at 6:46:35 PM

There really aren't any HOAs in the UK. Some newer houses have a covenant which resticts some things but people push back on those pretty hard.

by butshouldyou

5/21/2025 at 8:42:20 AM

One of those areas where policy action is desperately needed but no attention is paid due to media dysfunction. I think the UK would benefit from region-specific pricing, to move the datacenters closer to generation rather than urban environments. It would also encourage more embedded generation in expensive areas.

by pjc50

5/21/2025 at 11:28:17 AM

The cost for generators to connect is already based on region (TNUoS pricing).

by 7952

5/21/2025 at 9:49:09 AM

Politics however them collides, with "postcode lottery" headlines

Democracy really limits governments

by ta1243

5/21/2025 at 11:07:03 AM

Yeah. It would be more accurate to say that newspapers hate local government as a concept, but a lot of the public are happy to go along with that and get peeved about any difference which is pointed out to them.

(nobody ever describes house prices as a "postcode lottery"!)

by pjc50

5/21/2025 at 12:28:36 PM

Talk radio and TV are just as bad, as are the opposition. If Tories proposed it, Labour would be up in arms about postcode lottery. If Labour proposed it, exactly the same from the other side.

Doesn't matter how sensible it is, the other side will use it to score points. I can't believe for a second that Liberal Democrats think that James Dyson or Andrew Lloyd Webber should be able to avoid inheritance tax by buying tens of millions of pounds of farmland, but it's politically beneficial for them to do so.

by ta1243

5/21/2025 at 8:31:57 AM

Add smart storage and demand response, and you've basically got a decentralized resilience network

by BrtByte

5/21/2025 at 6:45:14 AM

It’s a true shame that the public utility commission is so corrupt that we lose the obvious economies of scale from grid-scale installations of same in favor of expensive rent seeking by a state-sanctioned monopoly.

I also have 60kWh of batteries in my kitchen, but for the average person who doesn’t want to deal with this stuff, having to admin part of the power grid is a tragic waste.

If the PUC and power company weren’t bastards, this could all be in a giant field somewhere staffed by a tiny fraction of the people who have to waste their lives dealing with it in their garages. So many unnecessary struts, so much caulk and EPO switches, so many inverters.

by sneak

5/21/2025 at 8:39:14 AM

The fact that so many people are turning their homes into mini power plants is less a triumph of individualism and more a symptom of a broken system

by BrtByte

5/21/2025 at 9:50:50 AM

Abstracting away from any particular grid regulatory environment, distributed solar and batteries make sense and make more and more sense as the cost reduces.

Another way of saying that, if we were playing a city simulator as a disembodied beneficent dictator you'd want distributed generation and storage as part of your grid.

In reality there's all sorts of complications, compromises, trade-offs, graft and politics but on balance those factors are working against distributed solar which is succeeding despite them.

Some people have a knee-jerk reaction to anything that requires legislation, regulation or subsidies which clouds the issue though.

by ZeroGravitas

5/21/2025 at 9:53:49 AM

There’s distributed and then there’s piecemeal. It doesn’t make sense to try to fit large energy storage safely inside every residential building.

You could build fireproof mini storage substations in blocks or subdivisions to load shift, but taking a chunk out of everyone’s garage space and forcing every person to do inverter and battery maintenance is silly.

by sneak

5/21/2025 at 3:15:56 PM

Yeah nothing about home install solar + battery soundly beating utility power prices even paying retail rates for equipment and labor for years on end, as prices on the equipment falls year after year, while utility power prices keep going up makes any fucking sense.

by alabastervlog

5/21/2025 at 6:57:38 AM

It turns out that the biggest cost of California energy is not generation, it's distribution and transmission.

Highly distributed energy lessens the peak demands on the T&D system, which means that the T&D system can be smaller, which greatly reduces the fixed cost of T&D. Utility scale solar requires greatly expanding transmission lines, to the extent that lack of transmission is the biggest barrier to adding solar to the grid in most of the US.

So even if installation costs of solar are higher on the grid edge, it usually makes a ton of sense, and this is evident in the payoff times of NEM3 systems that include batteries. As batteries get cheaper, or there's more vehicle-to-home systems out there, it will only increase.

This lessened need for T&D is the true reason that utilities in California hate solar and need to stop it. They can take a guaranteed rate of profit from anything they get to spend on T&D, but the same isn't true of generation. So utility solar, which requires building more lines and beefing up distribution substations more, lets them profit much more than residential solar.

by epistasis

5/21/2025 at 7:16:41 AM

How many office parking lots would be covered in solar carports immediately if the corrupt PUC paid reasonable rates for generation?

This solves the T&D problem too, as generation remains distributed.

It’s the money.

by sneak

5/21/2025 at 7:22:46 AM

Not so easy to reduce the grid load all the time, needs a big battery for every night and for multiple dark days you still need the grid a lot.

by looofooo0

5/21/2025 at 10:32:58 PM

Big batteries are actually very easy, and getting cheap enough that they account for a significant chunk of new grid assets when there are enough renewables.

Take the Texas ERCOT market, which is the closest thing to a free electricity market that exists in the US. A huge chunk of new grid assets are batteries, becuase they are one of the most profitable things to install right now (see the map at the bottom of the page)

https://www.eia.gov/todayinenergy/detail.php?id=64586

Additionally, many people are now buying EVs, and an EV stores 2-5 days worth of electricity. If big batteries on wheels are commonplace, then simpler and cheaper immobile batteries are pretty easy too.

by epistasis

5/22/2025 at 4:30:25 PM

Ok what do you do after 5 darkdays? You will need the grid.

by looofooo0

5/21/2025 at 10:22:44 AM

Spinning steam turbine generators also can't just turn on/off instantly. They need to ramp up/down. If you can't ramp up fast enough to meet demand, you have issues. When solar drops off pretty fast, and people come home from work and start turning on appliances, you suddenly have a huge amount of power needed from generators.

Even has a name: https://en.wikipedia.org/wiki/Duck_curve

The solution of course is more batteries, but you can't really incentivize non-peak generation until you get the batteries. That's part of the NEM3 change that the blog mentions, to change the incentives from just solar to solar and battery.

by ThatPlayer

5/21/2025 at 9:51:15 AM

Paying reasonable rates for generation also incentivizes distributed storage for anyone who wants to buy batteries and help load shift.

Large neighborhood batteries seem to make a lot more sense to me than batteries in every home.

by sneak

5/21/2025 at 9:20:30 PM

> Large neighborhood batteries

Boy people hated their HOA before, imagine how much they'll hate their HOA (because neighborhood batteries would need to be owned by someone, and that someone is the HOA) when they can cut off your power bc you left a garbage can out too long!

by KPGv2

5/21/2025 at 5:10:56 PM

Would be nice, the rate could be grid size battery/PV + cost savings from localized production. Not sure if it is economically feasible then.

by looofooo0

5/21/2025 at 10:38:18 AM

Is it the generation that cost, or the promise that you'll always have power?

Keeping capacity ready is probably the expensive bit.

by jopsen

5/21/2025 at 2:14:46 PM

you're making a big assumption here - that the demand peak coincides with the distributed generation peak. This is generally not true.

by eldaisfish

5/21/2025 at 3:54:15 PM

In California, the subject of my comment, it is true.

by epistasis

5/21/2025 at 4:07:12 PM

it generally isn't.

Peak demand on most electricity systems, including California's, is during the evening hours, typically between 18:00 and 21:00. This does not coincide with peak solar generation.

You can see this even as far back as 2018 via CalISO's own data. https://www.caiso.com/todays-outlook

by eldaisfish

5/21/2025 at 4:09:24 PM

That's because residential solar is eating up the daytime peak, thus the duck curve. Residential solar is already saving the state tons of money on T&D costs.

(And becuase the Wikipedia for duck curve shows a day in October rather than a summer day where the peak is much higher, yes the annual peak does coincide with when solar is outputting a ton of power.)

by epistasis

5/21/2025 at 4:16:50 PM

CalISO's charts disagree with you.

Gross peak demand is in the late evening, well after the solar peak. Solar noon in western California is around 13:00.

https://www.caiso.com/documents/gross-and-net-load-peaks-fac...

by eldaisfish

5/21/2025 at 7:37:56 PM

You misunderstand the charts, these do not take into account residential solar. The reason the peak is getting pushed into the evening is because residential solar doesn't even show up on the chart.

Look at the difference between gross and net: this is utility scale shaving off the peak. This is what is happening with residential solar too, which is not shown.

by epistasis

5/21/2025 at 3:22:36 PM

I installed a similar EG4 inverter and battery system and had a similar experience. The big problem I ran into was that EG4 inverters are NOT compatible with my state's power grid (Hawaii) but because I had so much power, it turned out I never needed to connect to the power grid but I am loosing out on selling power. (Check with your local power company before buying!).

Another problem I had was that a week after installing, one of the TIGO units burned up and started a fire that burned a hole in a solar panel. I only noticed the problem when I saw that one of the solar arrays wasn't putting out power. Replacing the defective unit solved the problem.

Also, I had assumed I would need a generator to power through consecutive days of dark clouds but I instead opted for Ford's Pro Charger Station which has a feature that allows you to power the house; no need for a generator. However, its been over a year and not once have I needed this.

My big takeaway is this: having energy abundance is the good life when you have all electric appliances. My EV (a Ford Lightning Truck), hot tub, AC, water heaters etc have been running over a year with no problems and zero costs after the initial investment.

by GratiaTerra

5/21/2025 at 4:03:32 PM

How many days can the truck power the house, and what's the longest stretch of overcast days you get (in Hawaii, I am gussing you get at least some sun almost every day).

by SoftTalker

5/21/2025 at 6:36:37 PM

Truck at 100% = 131 kwh, Minus 10% loss in transfer = 120 kwh House using 12 kwh/d = 10 days, up to 24kwh/d = 5 days

Local conditions are typically partly cloudy/rain but still system producing more than can be used.

by GratiaTerra

5/21/2025 at 9:43:16 AM

> I have a rack in the garage that pulls a little less than 1kw. That’s 1kw 24/7/365

This is insane. And here I am shutting down nightly the drives in my synology to save 20W.

by thefz

5/21/2025 at 3:01:48 PM

Hold my beer!

by sponaugle

5/21/2025 at 6:31:16 AM

I'm still curious what you'd need a rack consuming 1kw for… in your garage. From the photo, it looks like lots of storage(?).

by 9dev

5/21/2025 at 6:56:35 AM

My hard drives alone pull 200W idle and I don’t have that many. Cooling fans (in servers) pull 150W total most of the time but can be up to 300W. Each 10GbE NIC pulls ~40W. PoE switch gives ~30W to each of my APs, and uses ~80W itself, so there’s another 300W. All of my RAM pulls about 250W (admittedly there’s nearly 2TB of it in the rack, but still). Start adding up CPUs idle/average/max power and the numbers get way bigger.

If all he’s pulling is 1kW I’m jealous.

by jmb99

5/21/2025 at 8:23:57 AM

If I had more than 100 watts in idle hard drives, I'd start aggressively figuring out how to let them spin down. Maybe his drives are actually doing something 24 hours a day? But probably not.

Networking gear taking that much when it's not busy is really unfortunate. Did IEEE slack on adding effective sleep/downclocking features?

by Dylan16807

5/21/2025 at 11:16:39 AM

It sounds like the 10GbE is not fiber. With fiber, it would take around 5W only, depending on your needs. It's a bit harder to use, but fiber is really the better option if you want a serious homelab.

by mafuy

5/21/2025 at 11:01:12 AM

> Cooling fans (in servers) pull 150W total most of the time but can be up to 300W.

Oxide Computer found that going from tiny 20mm fans to 80mm dropped their chassis power usage bigly: they found a rack full of 1U servers had 25% of its power going to the fans (efficiency is to the cube of the radius).

* https://www.youtube.com/watch?v=hTJYY_Y1H9Q

by throw0101b

5/21/2025 at 1:54:22 PM

My mental model is that such a choice is why a data center is deafening: all those tiny fans spinning at hella rpm

by mdaniel

5/21/2025 at 12:21:55 PM

40W for a 10GbE NIC sounds crazy, my internet router has a dual 10 GbE Intel NIC with one 10GBaseT SFP+ and one 10G DAC and the whole router only draws 24 W (Lenovo ThinkCentre Tiny)

My whole “rack” draws about 120W total with: aforementioned router, Synology NAS with 4 drives, 2x10G+4x2.5G PoE switch powering a Ubiquiti AP, 16-port 1G switch, and a PowerBook 540c running AppleTalk routing

by kalleboo

5/22/2025 at 3:24:13 PM

Late response I know, but copper 10GbE nics pull lots of power, especially the old X540 ones.

by jmb99

5/21/2025 at 3:10:56 PM

I'm running 100G CWDM4s in my homelab, and those only take about 4w each for the optics, so I suspect with the PCIe card it is less than 10w.

by sponaugle

5/21/2025 at 8:19:31 AM

I'm curious, are you getting this with a kill-a-watt (or equivalent), or are you adding up wattage by specifications alone?

(I do have an epyc with a bunch of memory and storage, but never bothered doing the math since my UPS claims to be able to run with the average load for 30+mins)

by xarope

5/22/2025 at 3:26:41 PM

Measured at the UPS, which has 1W resolution. Confirmed its accuracy with an amp clamp on the circuit when running the UPS in pass-through mode. Efficiency is even worse most of the time since it’s a double-conversion (online) UPS that I normally run in full conversion mode - something like 80-85% efficiency overall, but because I fall back to generator power relatively frequently I just leave it there for convenience (in case I’m not home to switch it when the generator’s turned on).

by jmb99

5/21/2025 at 3:06:44 PM

1kW sounds pretty good to me!

My homelab is between 4 and 8 kW continuously, depending on what I have running. Cooling that homelab is another 400-1000 watts depending on outside air temp.

by sponaugle

5/21/2025 at 7:39:08 AM

Yeah, I wondered the same.

He mentioned that he refuses downsizing for ideological reasons, and I totally get that, but there's a certain amount of rightsizing that doesn't hurt in practical operation, and still let's you keep what feels like an awesome, big, complex model train setup in your garage.

Not all rust has to spin, almost no ports have to be 10GE, and a lot can be virtualized. Consumer CPUs have much lower idle than old xeons, and having less DIMMs with the same capacity also seems to pay off.

I'd be surprised if he couldn't cut that energy usage to 10% with a clear separation between hot and cold storage, and realistic expectations of bandwidth requirements.

But hey, I'm not judging. Solar power is great, and I don't mind waste as long as he can afford it and it makes him happy. Nobody drives the car they actually need either, and that is a much bigger problem.

by hengheng

5/21/2025 at 6:46:23 AM

1kW is less than a toaster, fwiw.

I draw 1-1.5kW for my servers in a spare bedroom. It’s not a lot of spindles/cores, just a few dozen.

by sneak

5/21/2025 at 9:51:32 AM

1kW continuously is 8760kWh per year. To compare, my house used 6200kWh in total over 2024, including heating.

Your toaster draws 1kW for maybe 5 minutes a day, which is maybe 30kWh per year.

The power in this comparison is not important, it's the total energy consumed (which is what you are billed for in the end).

by jaapz

5/21/2025 at 2:19:24 PM

yes, computers use a lot of energy, and spinning disks in my 40 hard drives use even more.

by sneak

5/21/2025 at 7:10:53 AM

Not many people run their toaster 24/7/365

by padjo

5/21/2025 at 8:28:27 AM

It is always surprising to me but small loads that are on 24/7 end up consuming a ton of energy. My 55W idle "homelab" consumes as much energy as my dishwasher, fridge and washing machine combined.

by nicolaslem

5/21/2025 at 9:58:50 AM

> 1kW is less than a toaster, fwiw.

Odd argument. A cheetah can run up to 110kmh, but that doesn't mean they can cross 110 kilometres in an hour.

by 9dev

5/21/2025 at 6:50:06 AM

I feel like they overpaid maybe because they got direct to consumer rates for the gear. If you would have went through a full on solar installer that solar system would have come out to less than $15k, throw in having to get the subpanel and a reroof you would maybe be looking at $30k all in. (Not including the batteries, but by the time he got to the batteries I feel like his budget was way overboard even going the non-microinverter route).

Make sure you are buying and not leasing from the company, have that all rolled into a single loan and then you claim the tax credits to help pay for the reroof.

To add to this, they take care of getting the certified roofers, the city permits for both the roof and solar and handle the PTO for you, which from what you called out is even more costs.

by leovander

5/21/2025 at 7:07:41 AM

No way, man - yes, they overpaid for some of their gear, but the labour cost of an installer ends up being most of what you pay.

No, the smart move here is to find out where the installers buy from, and buy from them. I never explicitly stated I was or wasn’t an installer, they just assumed that I was, as I was buying pallets of panels and kilometres of cabling.

The one advantage of going with a professional installer is that it makes it a lot easier to get grants - I had to spin up a company and invoice myself to get my rebate.

by madaxe_again

5/21/2025 at 7:13:43 AM

This is brilliant. Energy self-sufficiency often associated with off-grid eccentricity,looks engineerable for city homes. Goes to show that the more "personal" our energy solutions become, the more they reflect institutional failure. Wonder how this scales and if it does what are the political implications?

Funnily enough back home along the equator, having a solar setup still is a social signal of luxury!

by babushkaboi

5/21/2025 at 4:28:21 PM

This disabused me of the notion of doing it myself, lol. This is super impressive. Hope to one day be confident enough in electrical work. That and plumbing are the areas of home improvement that I still just would rather sub out.

But, this is such a cool article. The quotes on solar installs for some reason seem a lot higher than what you'd expect, given all the charts showing the absolute cratering of solar energy prices – but doesn't seem to work out that way when it comes to residential installations.

by gdubs

5/21/2025 at 5:35:34 PM

> This disabused me of the notion of doing it myself, lol.

The author did a very custom setup. If you want to DIY with a pre-integrated setup, you can enroll in Enphase's self installer program, and complete their online coursework:

https://enlighten.enphaseenergy.com/manager/registration?_gl...

I think EcoFlow may have a similar option.

by danans

5/21/2025 at 8:48:00 PM

Ooh, thanks for this. I've been considering some metalworking classes, something like this could also be really fun and enriching.

by gdubs

5/21/2025 at 9:30:41 PM

I still recommend hiring a licensed electrician to do the actual physical installation, because it's easy to mess up.

by danans

5/21/2025 at 1:28:55 PM

I'm in Texas and designed our own solar+battery setup in '21. I had an installer handle that bit and the interconnect though. I found the "secret" was the to leave room for expansion.

In Texas, residential grid-tied solar can be up to 20kWh so I chose cells that got me to 19.96kWh

Then I added an 29kWh battery stacks (18kWh total) but each stack could go to 18kWh (36kWh total). Then I also used a pair of Generac inverters which lets me get two more stacks for 72kWh total.

My goal was resiliency, not sufficiency, so I use it grid-tied so I charge during the day and use at night. When there are storms coming, I flip it to "priority backup" which will prioritize charging.. even using the grid to do it if there's not enough sun.

Anyway, it's been in production since January '22 and my annual* electric bill is ~$1100. Even better, when we have an outage (occasional as we live in a heavily wooded area) if our stack is full, we have ~5 days of battery backup for the fridge, a handful of appliances, and our Starlink.. therefore we have safe food storage, safe food prep, and non-terrestrial communications.

Of course, this cost ~$80k to get there in 2021 (aka before crazy inflation)

by caseysoftware

5/21/2025 at 1:38:47 PM

> Anyway, it's been in production since January '22 and my annual* electric bill is ~$1100.

A more helpful comparison would be to see your electricity bill before and after.

For comparison, I’m in an area with low electricity rates and I don’t run A/C at the level of someone in a Texas climate. My annual electricity bill is barely higher than yours but I don’t have any solar at all. Absolute electricity bill numbers don’t translate well.

by Aurornis

5/21/2025 at 6:29:17 AM

This is fantastic. Looking at the absolutely massive cost differential between DIY and full-service solar installers, the DIY option looks pretty pretty tempting. My main concern was 1) actually getting through the local permitting process, and 2) what a potential purchaser would think of a DIY system when I go to sell the house.

Seeing that somebody has done it is very inspiring, and if I didn't see a high chance of moving in the next 5 years I'd be on it tomorrow.

by epistasis

5/21/2025 at 6:47:43 AM

I have the advantage of living totally off grid and not planning on ever selling the place, so I can have whatever screwy setup I fancy.

Well - I say “off grid” but I’ve built a grid - I now have over a km of buried SWA cable linking the three houses on our land, battery banks at each (60kWh of OPzS down at the mill, 15kWh of LiFePO4 at each of the others), and victron inverter-chargers all over the shop. Two arrays of panels each 8kW, one winter optimised, one summer optimised, and planning on adding a third to make more of the morning sun, as we are in a deep and steep valley with awkward topography. Have mucked around with hydro on and off before landing on a plan for an overshot waterwheel using bits of a burned-out ‘88 hilux, which is my current project. Pessimistically it will give us a constant 1.5kW, but theoretically it should end up nearer 3. Either way, that’s a lot of power. Right now I’m stuck running a Honda generator off our biogas in the winter, and it works, but it’s noisy and I have to go yank the cord to start it, usually in the pouring rain.

Using victron and fronius gear all over, frequency shifting to control where the power goes, and home assistant to automate the whole shebang where it’s beyond what the inverters and chargers can do themselves.

As we aren’t grid connected, the permitting process is… “you do what you want”.

It’s all far, far more straightforward than most people think - the hard bit is the physical install, as you’re inevitably lugging awkward panels onto roofs or up cliffs (going for smaller panels can help with this if you’re doing it without any help), or incredibly heavy batteries to wherever they need to be. The lithium arrays weigh about 150kg each, the lead array the better part of 2000kg.

People assume it must have cost hundreds of thousands of euros, but no - all in it has been about €30k, and our ongoing costs are zero.

by madaxe_again

5/21/2025 at 7:20:00 AM

Yeah, we once unmounted our panels so painters could do some work on our roof. It was pretty trivial to do. The tricky part is the electrical work.

by davedx

5/21/2025 at 7:40:17 AM

That sounds amazing, would love to be able to check it out.

Out of curiosity, have you ever calculated the cost of the batteries over their expected lifetime ?

by 4gotunameagain

5/21/2025 at 6:48:52 AM

DYI if your dad is an electrician. I wonder what the total would be if he tallied his dad’s assistance at market rates - probably not that much less than the initial quotes he got from professionals.

by baq

5/21/2025 at 7:17:44 AM

Depending on the jurisdiction you could be saving a whopper amount on taxes. Where I live the service tax could be anything up to 23% and the guys doing the work have to pay income tax. Insurance would also be a factor where I live too. There are massive savings if you can get a friend to do it or if somebody does it for cash (which is considered tax evasion)

by rusk

5/21/2025 at 7:37:20 AM

"they have come out and said what we knew all along: they only care about profits."

Not the detract from the rest of the article, but - it's a company, what did you expect?

by g0ran

5/21/2025 at 10:29:14 AM

It’s a public utility, possibly with monopoly pricing power. There are other well known economic models around for managing public utilities, that mean profits don’t get prioritised above everything else

by davedx

5/21/2025 at 8:23:59 AM

I’m cynical, but most companies do have some scruples.

Eg basic environmental care/policies or how they handle staff and customers.

by lostlogin

5/21/2025 at 8:46:18 PM

The author says that the resale value to PGE is 25% of the buying price.

Is there some way to get a better rate by selling CPU time instead, when the sun shines and batteries are full? Especially if you have your own server rack.

I have computing needs that can wait for 12/18 hours. Would it make any sense to have those processed by distributed solar server farms between 11am and 5pm? They just take data in and send results back, using their own "free" marginal kwh.

It would reduce the need the connect to the power grid, but still benefit from selling solar power indirectly.

Cloud providers may just be so much better at doing this already?

by hurtuvac78

5/22/2025 at 6:08:27 AM

Mining Monero maybe.

by bauruine

5/21/2025 at 7:37:37 PM

I've interested in solar and batteries but unfortunately the return would be too long for us if we hired a contractor and I'm not confident in my own skills to pull it off correctly.

Mostly I want an easy whole home battery just for some arbitrage. Our rate plan has a 4 hour peak period of $0.27/kwh vs $0.14/kwh off peak. Of course the peak time is when we actually want to use a lot of energy running our AC and other appliances.

Unfortunately I haven't found any DIY stand alone battery systems that offer the simple scheduling I need since most seem to be only backup systems.

by ellisv

5/21/2025 at 6:42:15 AM

And over here in NL we're going to be _charged_ when returning power to the grid in 1.5 yr... I'll be running my airco to burn off those kWh's :P

by brnt

5/21/2025 at 6:50:28 AM

The grid needs batteries and that’s how they make you buy some. They have good reasons - look at Spain.

Running aircon to burn the excess is better than feeding an already overloaded grid, too. The second best outcome for them, neatly contained in a single euro amount.

by baq

5/21/2025 at 7:17:04 AM

> I'll be running my airco to burn off those kWh's :P

As an American I welcome you to our national pastime: burning kWhs on aircon! :P

by elcritch

5/21/2025 at 7:21:46 AM

We've been on a dynamic contract for the last year (also in NL), it's worked out pretty well (Tibber).

by davedx

5/21/2025 at 8:40:20 AM

Don't you have energy cooperatives to avoid this in the Netherlands ? According to rescoop.eu i did find hetcooperatie.nl, energiesamen.nu & lochemenergie.org.

Even if you are instead in Newfoundland, maybe ask cecooperative.ca if there us a project to create one in your province.

by miniwark

5/21/2025 at 7:37:01 AM

Already happening in Flanders for those on dynamic pricing.

by markvdb

5/21/2025 at 6:59:49 AM

What should the grid operators do with all that energy that comes in at noon on a beautiful sunny day?

by tralarpa

5/21/2025 at 7:29:36 AM

Pump it to the storage. Building something like https://www.energyvault.com/products/g-vault-gravity-energy-... is impossible for a home owner. But the country scale energy provider can build such thing.

by delamon

5/21/2025 at 4:43:01 PM

Technically almost all homes have a wonderful energy storage system already -- their hot water heater tank.

One can imagine a setup where you've got a hot water tank and a mixing valve that allows you to heat your water up to some very high temperature and then mix that down to "safe" hot water for the house. Have that run in "heat from grid if below this threshold, otherwise conditionally heat with surplus energy if the water's below this temperature"

by cduzz

5/21/2025 at 8:16:05 AM

Great idea, but that also comes at an additional cost - who would you recommend should pay for that cost?

by kleiba

5/21/2025 at 8:36:38 AM

Storage comes at a cost, but storing cheap/free power offsets even bigger generation costs. So the power company should pay to build storage.

There's a point where the grid has so much solar power that we need to start shedding production as a general rule and not just as an intermittent temporary measure, but I don't think we're anywhere near that point.

by Dylan16807

5/21/2025 at 7:18:23 AM

Hmmm, run direct carbon capture systems?

by elcritch

5/21/2025 at 7:10:53 AM

Heat up molten salt, or shipping containers full of sand. It’s a surprisingly high density and cheap way to store an awful lot of energy. Don’t have sand batteries here yet, but they’re on my todo for deep storage of excess energy, which I currently just dump as heat into the air.

by madaxe_again

5/21/2025 at 3:19:09 PM

I don't know. Salt (NaCl) is corrosive. Specific heat capacity is not that high (about 1/5th of water per weight). Suppose you have cubic meter of molten salt at 800°C in a dewar, how do you get the heat out again?

by rmu09

5/21/2025 at 5:41:12 PM

Even with tariffs batteries are very cheap. Into the 4 year mark my cost per kwh is down below $0.02 because I end up using excess power for all sorts of things because it is "free".

https://news.ycombinator.com/item?id=40877337

by duffpkg

5/21/2025 at 4:32:11 PM

Pretty cool. I'd love to get into solar DIY but it seems pretty daunting. I moved in to a place recently with an (apparently very old) 7kW rooftop solar system without a battery, and I called the original installer to talk about what my options are if I wanted to expand it, either adding more watts or adding a battery. The overall take-away from talking to the installer was that it wasn't worth it because my existing system uses some different, older technology, and that making any substantial improvements to it would change my "NEM" whatever that means. The way I understand it, it would move me into some other, more expensive regulatory regime. I don't know--my head was spinning after the conversation, and I was basically convinced to just ignore the system I have and not touch it.

by ryandrake

5/21/2025 at 2:38:16 PM

>We can't all live in SF

Thanks to California zoning

by M3L0NM4N

5/21/2025 at 8:54:36 AM

I have a minor interest in this subject as well, and after some thinking I realized that my personal solar interests are best served by electro-mechanical harvesting of solar energy, first and foremost .. since a full-blown EV solar rig would require the purchase of components I cannot myself personally make very easily.

This summer I'm building a solar oven to cook bread and veggies with .. and if this works well, I'll build a solar death ray to play with while I wait for lunch.

It seems to me that this is a potential route for the popularization of off-grid/local-energy-harvesting movements to gain more traction. Sure, its nice to have a whole roof full of PV panels and a battery bank to sip juice from now and then, but this still requires a heavy investment in foreign-originated parts and materials.

A solar oven/solar death ray, however, is a lot more feasible to produce locally.

by aa-jv

5/21/2025 at 7:41:26 AM

Okay I finally did this earlier this year too and it took quite a bit less than that. Started with impulse buy of invert at an online auction end of January. Installed last panels end of April. 3 months. Quite a bit of it was waiting for third parties or just me being lazy and not ordering parts I needed. I've wanted them for years beforehand so I did some research.

For actual labor - it's about half days to install roof racks (I have shingle roof so quite a bit of time on angle grinder). Another half day to put panels on (requires 1 or more helpers), run a cable thru roof space. I've installed 12 panels on 2 facia.

My hack was hiring electrician to install inverter so I can export to grid (I'm in New Zealand).

by dzhiurgis

5/21/2025 at 8:42:39 AM

Funny how half the battle is just… remembering to order the right parts ahead of time

by BrtByte

5/21/2025 at 9:14:53 PM

Kinda by design. Didn't want to do shoddy things or have to re-do which means waiting and taking things slow.

by dzhiurgis

5/21/2025 at 2:54:25 PM

We’ve recently had some crazy storms and power outages and my Ecoflow units kicked in and worked perfectly. I have a River 2 which I use as a UPS for my Mac Mini + Monitor at my desk and a River 2 Pro as a UPS for all my Ubiquiti networking, Protect cameras, and severs in my racks. Then I have a Delta 2 I can hookup to the two Rivers to add additional charge. Just pulled the trigger on a 3600watt gas generator off Amazon as well incase of extended outages. While not whole home backup by any means it’s a solid setup for electronics and server gear.

by nodesocket

5/21/2025 at 7:46:35 PM

> $30K

Wow. That's ten years of electrical bills where I live in Texas, and you also have to deal with the increased water leakage risks, any maintenance issues, storm problems, etc.

by KPGv2

5/21/2025 at 12:29:43 PM

I missed the "power" when I skimmed the headline and clicked the link. I was slightly dissapointed when I finally realised that the OP is in fact not building his own solar system.

by growt

5/21/2025 at 12:03:14 PM

With power issues in Nigeria (basically no power from my perspective), I have been building my home solar system. Currently at 9kw solar panels, 10kva inverter with 30kwh Chinese LFP. Spent about $7,000 so far. Looking to eventually get to 60kwh and at least 20kw in panels because of air conditioning needs.

Waiting for government, my kids currently in primary school would probably have graduated from college before they fix the power situation (they are currently fixated on building roads to nowhere).

by bmqpo

5/21/2025 at 8:06:47 AM

This solar installation is quite large and quite expensive.

There is a whole cottage industry of DIY 48V 15kWh batteries based on LFP prismatic cells (16x) and special battery case resulting a price of around 1500 Euro for 15 kWh.

A DIY setup is quite doable, Deye (EG4) or Victron make suitable inverters.

The continuous 1 kW power draw I find Ludicrous, probably especially as a European. I would realy rethink what is absolutely necessary. Huge data storage was my hobby but the storage server is only turned on when required, saves a lot of power.

by louwrentius

5/21/2025 at 9:10:37 AM

We also setup our own off-grid solar system, almost 4 years ago now. The cost was much lower due to lower import fees and lack of regulations where I live, it was altogether somewhere between $3-4k total, for 16 panels, mounting rack, inverter (with backup inverter), mptt, 12 acid-lead batteries, etc.. We saved so much money, and fewer headaches, since state electricity only came around 5-6h a day and people relied on scammy-mafia generator providers that ask for insane prices.

by venamresm__

5/21/2025 at 7:15:20 AM

He estimated break even at 2-3 years.

by davedx

5/21/2025 at 5:29:54 PM

> Missing site diagram placard at MSP

I got dinged for this on the first inspection of my own self-installed solar+battery system.

A lot of signage companies don't know how to do the placard, but the company that I found that knows how was PVLabels:

https://www.pvlabels.com/04-645-map-placard/

by danans

5/21/2025 at 2:33:47 PM

Great writeup! Seems bizarre to have a furnace in the Bay Area. Air-source heat pumps and heat pump water heaters are fantastic these days.

by heytakeiteasy

5/21/2025 at 6:38:50 AM

With the rising price of energy, this is a fantastic idea

by yasir326

5/21/2025 at 7:10:38 AM

Well big chunk of the electricity cost are fixed cost, meaning if enough people lower their bill with PV and batteries then prices will have to rise for their connection. In fact some suggest that it would make more sense to let people pay a flat rate.

by looofooo0

5/21/2025 at 11:11:12 PM

The technical work is lovely. I would have liked to have seen (though I respect that it might be personal or PII) a working out of the accounting, specifically about the amortized cost of batteries vs just eating PG&E costs and treating them as the battery.

by cranky908canuck

5/21/2025 at 1:35:51 PM

Saving this for when my parents moves - they're on NEM 1 and will freak at the rates for a new solar install. Right now the excess power goes to an EV and then the grid since the power import/export rates are almost 1:1 but after the move these in home batteries are going to be crucial.

by ctkhn

5/21/2025 at 7:15:13 AM

I don't understand the comment about the small battery from installers. Don't they allow customization?

by gniv

5/21/2025 at 4:29:59 PM

Suspect it would have been cheaper to invest money in upgrading the homelab and aircon to more efficient. Not downgrade, but rather moving to newer lith nodes etc. Tackling the usage before bigger battery system often makes sense

by Havoc

5/21/2025 at 5:32:04 PM

The solar system will pay for itself within N years, and then he has free power for as long as the batteries and panels last

by somanyphotons

5/21/2025 at 7:48:48 PM

>pay for itself within N years

The total outlay in that calc is affected by how big of a system you need though.

If you've got no obviously inefficient gear then yes you just put in a system of whatever size is needed.

If you have easy wins on the consumption side then you do that first.

Silly example but say you could eliminate half your consumption with a once off $100 spend then you do that. You don't pay through your nose for an system twice the size just because of ""free"" power later.

Where that cutoff point lies will require calculation, but chances are old enterprise racks are on the wrong side of it.

by Havoc

5/21/2025 at 10:47:16 PM

It's really unlikely that most people will gain a lot of money from these kinds of installations nowadays (an EV probably tips that somewhat).

The big benefit is the resilience. Since you are using them every day, they will be far more likely to work in the event of an outage than a gasoline generator that you test once a year.

by bsder

5/22/2025 at 8:37:41 AM

How well do solar panel resist to Hail or tornado ? Getting Tree branches thrown at it or whatever happen when there is a lot of wind ?

by aucisson_masque

5/21/2025 at 8:51:19 AM

Am interested in the DC-AC—DC- Battery-AC vs DC-DC-Battery-AC efficiency argument. As in there must be a DC-DC conversion happening to charge batteries appropriately.

by speedbird

5/21/2025 at 10:31:43 AM

Stepping voltage up or down isnt as lossy (or expensive) as converting from AC<->DC

by davedx

5/21/2025 at 6:18:23 PM

As someone not into electronics, can you explain how that works. I'm only familiar with transformers which, of course, require AC?

by rssoconnor

5/21/2025 at 8:19:58 AM

forget the technology, what is that gorgeous snake-like plant in the picture by the blue stairs? I need that

by meitham

5/21/2025 at 8:36:01 AM

Not sure if the identification by the PlantNet is the correct one, but you may check [1]Asparagus aethiopicus

1 https://www.backyardboss.net/asparagus-fern-guide/

by elmolino89

5/21/2025 at 9:40:16 AM

Thank you, I think that's the one!

by meitham

5/21/2025 at 1:18:09 PM

If you like the general shape you may look into various Echium species. Echium wildpretii is just stunning.

by elmolino89

5/21/2025 at 2:54:09 PM

What happened with the broken panel shown at the end of the article?

by bredren

5/21/2025 at 7:14:58 AM

[flagged]

by donnachangstein

5/21/2025 at 8:17:15 AM

That cellar wouldn't stay that temperature once they put a 1 kW heater element in there though.

by Cthulhu_

5/21/2025 at 7:27:52 AM

Yeah, because you don't lose anything by living in the middle of nowhere.

There are benefits to being in the bay area, too. This happens to not be one of them.

Living in "a part of the country that has basements" is no utopia either.

Also: my house, in the bay area... has a basement.

by borski

5/21/2025 at 8:37:27 AM

Many of us like where we live, like our jobs and like our warn out old houses.

There are plenty of more efficient ways of doing things, but I still stuck solar on this old, energy inefficient house.

by lostlogin

5/21/2025 at 8:33:53 AM

Yeah, he spent a ton, but he clearly wanted to stay where he is and took control of the situation in a way that fits his priorities

by BrtByte

5/21/2025 at 7:17:47 AM

Ah yes...because the simple solution is always "just pack up your life, leave behind your family and friends, and relocate half way across the country".

by esskay

5/21/2025 at 8:44:49 AM

Unironically that is what cost-of-living is forcing a lot of people to do in coastal cities. If you have a cushy six figure salary you aren't faced with that reality, but it's different for median-income.

by willis936

5/21/2025 at 7:32:50 AM

Relocating is a simpler ask to most ordinary people than is turning their garage into a battery vault.

by donnachangstein

5/21/2025 at 8:06:11 AM

That's the most ridiculous claim I've seen in a while.

Giving up one foot of space along one garage wall is not a big deal. And if you're worried about physically getting the batteries into place, hiring people would still be cheaper than movers.

Also, a basement that removes cooling costs for the home lab would not make a big difference. If the 800W A/C unit runs 8 hours a day for 4 months out of the year, then it's only about 10% of the home lab power use. Since it's not needed at night it's probably even less.

by Dylan16807

5/21/2025 at 8:09:01 AM

From logical/cost perspective maybe, from emotional not so much... is it really that hard to see it?

by jajko

5/21/2025 at 8:16:12 AM

Yeah sorry but thats the most insane take anyone could have. You're again quite litterally saying upping sticks and moving across country, so new job, losing friends and family, etc is the best option, vs losing a big of garage space...

by esskay

5/21/2025 at 8:18:01 AM

[dead]

by OhNoNotAgain_99

5/21/2025 at 6:15:35 AM

To save you the click, it’s about building a solar electricity system.

And not a cosmic solar system.

by stevoski

5/21/2025 at 11:06:54 AM

Ah, the title was edited, so now my comment seems nonsensical.

by stevoski

5/21/2025 at 11:11:56 AM

to make an apple pie from scratch, you must first create the universe.

by pantalaimon

5/21/2025 at 3:15:53 PM

My favorite Cosmos episode (#9)!

by sponaugle

5/21/2025 at 2:35:57 PM

Imagine if America didn't have any tarrifs or constrains on Chinese advanced goods like EV cars and Solar Panels.

by EcommerceFlow

5/21/2025 at 8:22:24 AM

Guy claims he's tired of paying for electricity because of the "ludacris" (sic) costs so he's going to "DIY". Yet, first thing he does is pay a guy to do it.

by bloodyplonker22

5/21/2025 at 2:24:39 PM

Yeah. He didn't even mine the lithium for his batteries himself, what a sham.

by Mawr

5/21/2025 at 8:36:38 AM

Yeah but come on, there's a big difference between paying someone to design plans vs handing over the whole project to a solar installer

by BrtByte

5/21/2025 at 8:49:50 AM

capex vs opex

by lvturner