Terence Eden
@Edent@mastodon.social  ·  activity timestamp last week

What would it take for our home to be Solar Self-Sufficient?

Work in progress, but I think I have the answer.

🏠 I live in an ordinary house in suburban London.
☀️ Our solar panels generate 3,800kWh per year.
🔌 We use the same amount of electricity per year.

After crunching the numbers:

🔋 Capturing all our solar excess needs a 1 MegaWatt-hour battery.

#Solar#SolarPunk

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Zoe
@z303@mastodon.social replied  ·  activity timestamp last week
@Edent An interesting problem. Thinking about current battery sizes. So to get a 1MW battery in the same physical package as 100KW currently. You need about an order of magnitude. I've not kept up on electric aviation. That would seem to be what could drive very energy dense, small packaging of batteries. Static batteries would have to care less about weight.
Sheddi
@sheddi@mstdn.party replied  ·  activity timestamp last week
@Edent
More like £100k, if you buy 30 of these:
https://www.fogstar.co.uk/collections/solar-battery-storage/products/fogstar-energy-32kwh-battery?variant=55157091205497

As I'm sure others have commented, it would be more cost effective to add extra PV panels so you don't need to save the midsummer peak all the way through to midwinter. I've not modelled it but I suspect adding 10kWp of PV somewhere (carport? conservatory? gazebo?) for £10k would let you halve the battery size.
Daniel Durrans
@dan@mastodon.durrans.com replied  ·  activity timestamp last week
@Edent I wonder what used EV batteries will do to the market. The percentage of EVs in company fleets continues to increase and while we have gone through a few replacement cycles, those vehicles are likely still in the second hand market. But in another 5 years? 10 years? We should see a reasonable volume of EVs at end of life... but those batteries will still have life left in them for non-transport use.
Terence Eden
@Edent@mastodon.social replied  ·  activity timestamp last week

To be clear, I've no idea if this is possible. Maybe there are fundamental limits to the size, cost, and capacity of batteries.

But it shows that it is technically feasible for homes in the SE of England to use rooftop solar to generate all the electricity they need across the year.

Yeah, it doesn't account for getting an electric car or heat-pump. But panels should also get more efficient as well.
gary
@gary_alderson@infosec.exchange replied  ·  activity timestamp last week
@Edent right now you need like 4 pv panels to power a small mini pc ai cluster - it helps productivity and is also much more efficient and faster to keep most (not all obviously) compute local - you will upgrade less and just add a node or two when you need them but it is easily scalable so good for the smb sector. you are basically paying for 5 years of elec upfront and then it is free - that's reasonable. battery tech and materials science will help speed things along and catalyze advancements, the hardware is starting to be fast enough and cheap enough (unified mem) that we see a host of tech related trends manifest/outperform
DamonHD
@DamonHD@mastodon.social replied  ·  activity timestamp last week
@Edent My challenge was to cover all our heat (now c/o a heat pump) also. We are about carbon neutral and energy neutral in an EPC A house. My CAPEX guestimate was a bit lower last time I had a go, but another issue is that the battery would take up 50% of the volume of the house, so I'd need to dig a basement at least. Which is tricky as we are poised over much of the local sewage system...