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What a year of solar and batteries saved us in 2025

scotthelme.co.uk

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Re: What a year of solar and batteries saved us in 2025

#281

Post by tzs »

ozim wrote: post #263
lotsofpulp wrote: post #196

Earlier quoted context omitted.

Run for political office espousing Texas' famous "freedom" that does not allow you to modify your own home.

From what I quickly checked you can modify your own home there is an exclusion for doing electrical work on your property - seems like main panel would be somehow excluded from what qualifies as "yours".

That exemption is from the state code and applies to "work not specifically regulated by a municipal ordinance that is performed in or on a dwelling by a person who owns and resides in the dwelling".

They said it was city code causing their problem.

Re: What a year of solar and batteries saved us in 2025

#282

Post by abdullahkhalids »

LordDragonfang wrote: post #231
magicalhippo wrote: post #144

Earlier quoted context omitted.

There was some research[1] that strongly suggested that varied use makes them last much longer than the steady use that most battery tests do. That is, bursts of high-current draw followed by moderate draw etc vs the constant current load typically used when evaluating battery performance. From the paper: Specifically, for the same average current and voltage window, varying the dynamic discharge profile led to an in…

Huh, unexpected is right. Bursts of heavy usage being better for longevity than steady usage goes against pretty much all conventional engineering wisdom.

Without knowing anything about it, I would posit that degradation accelerates the longer the battery is kept above some threshold temperature.

So, a heavy-burst+low results in a sudden high temperature then settling into a lower temperature. Steady flow keeps it at moderate temperature (above threshold) for a long time.

Re: What a year of solar and batteries saved us in 2025

#283

Post by KaiserPro »

youngtaff wrote: post #78
kccqzy wrote: post #2

Good analysis. And kudos to the author for saving money. But still 21.6MWh per year excluding solar production seems too high for a household. I use electric heating and drive an electric vehicle, and my household annual energy consumption is about one fifth of that.

I think Scott's usage is high – I think he mentions between £300-400 / month – but then he's got a hot tub, server rack as well as the cars. We still have an ICE car and gas central heating but our combined electricity and gas bill is around £140 / month Plan to go to EV and heat pump in our next house though

external wall insulation and triples glazing first! We did it and made winter ~10 degress warmer, and summer 15 degrees cooler. its cheaper than the solar/battery install.

Re: What a year of solar and batteries saved us in 2025

#284

Post by systemtest »

Aperocky wrote: post #206
systemtest wrote: post #98

Earlier quoted context omitted.

Is delivering back to the grid economical in California? Where I'm from people disconnect solar panels on sunny days because it costs them money to return to the grid.

Is the disconnect automatic? what happens when you're not connected to the grid but battery is full?

This is for solar only installations. People are advised to flip the breaker of their solar installation when energy prices are negative as it would cost them money if they deliver electricity to the grid. This helps to reduce strain on the grid.

Re: What a year of solar and batteries saved us in 2025

#285

Post by darknavi »

port11 wrote: post #239
Aromasin wrote: post #184

Earlier quoted context omitted.

He mentions that he has a server. It wouldn't surprise me if that consumes the majority of that.

People need to stop using the old Mac Pros for home servers, jeez.

I had a old, cheap, used Dell R710 that I bought used in ~2016 until 2025. It only took a few months of running a new, much more efficient server to pay for its self.

Re: What a year of solar and batteries saved us in 2025

#286

Post by coryrc »

pier25 wrote: post #270
coryrc wrote: post #234

Earlier quoted context omitted.

Do you have electric heat? Do you have automobiles and do you fuel them with electricity?

We do use electric heating from time to time but it's not constant. No electric cars. Still a 15x increase seems huge. Increasing electricity production 10x to electrify cars is not going to be achievable soon. Either via the power grid or home solar panels. Most people cannot afford to invest $40k in solar panels, batteries, etc.

Well, people who live somewhere where they need heating use more energy to stay alive than those who don't. Too bad California is so expensive because we could decarbonize the US significantly just by making it affordable for people to move there from Northern states.

Re: What a year of solar and batteries saved us in 2025

#287

Post by yomismoaqui »

torginus wrote: post #258
raddan wrote: post #199

Earlier quoted context omitted.

I installed a 16.5kWp ground-mount array a month ago. I live in the US Northeast, in a mountainous location that means we get late sunrises and early sunsets. Nevertheless, based on my one month of data, it looks like we can generate all the power we need for our household on a sunny winter day, excluding electric vehicles. Even on overcast days, we can sometimes offset a significant portion of our usage. My locale d…

Here in Europe, we got more than a month's worth of foggy, cloudy weather (something that looks like will keep being a thing), which is something I became painfully aware of as an owner of a solar setup. No amount of battery banks can tide over such a long stretch. By the way, let me ask you - considering your location, you must be getting a lot of snow, how do you deal with it, is it a problem? Panels are quite hard…

Where in Europe? Between Spain and Denmark there is a lot of variance in temperature, sun and rain...

Talking about the weather "in Europe" is like talking about the shoe size a family of 10 wears.

Re: What a year of solar and batteries saved us in 2025

#288

Post by Veserv »

labcomputer wrote: post #279
Veserv wrote: post #216

Earlier quoted context omitted.

What do you mean? It did pan out for Tesla. Faking a single demo granted them 75% more ZEV emissions credit government subsidys [1]. That increased their profits by hundreds of millions of dollars. All they had to do was go on stage and “swap” a battery without any clear video of the process and never “demonstrate” it ever again. This is a company known for faking prominent demos like the FSD demo (where it crashed i…

They didn’t fake the demo, but the legislature quickly rewrote the law because it was intended to give Toyota ZEV credits for hydrogen cars. Tesla did briefly operate a swap station at the site of the Harris Ranch Supercharger until California changed the rules. There are several reports from people who used it on teslamotorsclub.com, and I saw it with my own eyes. Hilarious that your source is Ed Neidermeyer. Perhap…

Cool. Then if you are not lying, then it should be easy to present a clear video demonstrating the automatic battery swapping machine in action and swapping out a battery in 90 seconds as claimed in the demo.

Re: What a year of solar and batteries saved us in 2025

#289

Post by MisterTea »

jstsch wrote: post #12

Battery prices are getting really low, if you're willing to do some DIY. Just received a 15kWh battery from China. A 'Humsienk'. Combined it with a GroWatt SPA3000TL-BL inverter. Total price, 1600 euros. So close to the magical 100 euros per kWh. Driving it with some interesting combinations of Raspberry PI's and serial interfaces and custom written Go code, but it works... :)

> Driving it with some interesting combinations of Raspberry PI's and serial interfaces and custom written Go code, but it works... :)

What protocol is it speaking? I've seen some of the more mainstream models call out that they use Modbus but all the cheap import models either might use Modbus or some custom protocol you have to reverse engineer or hope someone else did.

Re: What a year of solar and batteries saved us in 2025

#290

Post by MisterTea »

f1shy wrote: post #39
jstsch wrote: post #12

Battery prices are getting really low, if you're willing to do some DIY. Just received a 15kWh battery from China. A 'Humsienk'. Combined it with a GroWatt SPA3000TL-BL inverter. Total price, 1600 euros. So close to the magical 100 euros per kWh. Driving it with some interesting combinations of Raspberry PI's and serial interfaces and custom written Go code, but it works... :)

> Battery prices are getting really low, if you're willing to do some DIY. Willing and allowed. In some countries it can only be done by certified electricians.

Then pay one to inspect it and sign off for you.
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