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Comment by KaiserPro | Hacker News Reader

In the UK you'd need a class D "loi-sonce" to be able to pull the shipping container sized battery trailer for that to work.

However, if you were wanting to use pure lead acid batteries for your house, because you'd be doing slow charge/discharge you'd probably be able to get away with just 1100 130ah lead acid car batteries.

I mean you'd be optimising for peak current, which isn't what you'd want. However it could be interesting to see what happens when you have ~500mega Amps at 48v. (24Mw would heat your radiators up pretty quick. )

for lithium, then you'd need 12-14 secondhand tesla/polstar batteries, which if they caught fire, might be a challenge to contain.

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"loi-sonce", would be better "loi-sunse". That 'o' is very jarring.

I was going for beeeergminghum, but for cockney, the o is indeed jarring

1100 car batteries might cost maybe $100-$200k and need replacing every 4 years.

Lead-acid car batteries are designed for high short-term current supply, for starting engines, not longevity. You can buy deep-cycle lead-acid batteries that last much longer, on the order of over ten years. Moreover, lead-acid batteries wear out when you discharge them too much more than by time elapsed, so taking good care of them can make them last even longer. Lead-acid batteries are great for standby storage, where you normally only discharge them a small amount between charging, but then need to use the whole capacity every now and again (for instance if you have a few dull days).

LiFePO3 batteries don't take as much wear from cycling, so they usually wear out from time elapsed instead of over-use. It's economically sensible to cycle LiFePO3 batteries as frequently as possible to get as much "benefit" out of the investment. They're great for time-shifting energy production by charging them at a cheap time of day and discharging them when you need the energy at an expensive time of day.

Did you take into account that lead acid batteries are recommended to only be discharged to 50% especially when used for solar ? If not thats now 2200 batteries and $200-$400K.

I eyeballed the maths on that. 1100 * 12v*130ah should give you a .7mwh of leeway to not do "deep" discharge.

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