50kWh of battery is quite cheap compared with a house and will keep you going a long time without grid power
For grid independence you need to have either multiple redundant sources of energy and a backup generator (which consumes a fossil fuels), an absolutely massive battery (far larger than is economically feasible) or a grid hookup.
I've reduced the energy consumption of our house about as far as it will go without seriously affecting quality of life, and yet it won't go down below 500 W draw on average, so about 10 KWh on a daily basis. On an annual basis we're 7.7MWh surplus but in winter we are net consumers. Starting March 1st we are in the plus on a daily basis and we could - if we had a battery, which we do not - be neutral. But we're still heating with gas and that leaves four months to cover or about 120 days.
During those 120 days we consume 4 times 350 KWh, so 1400 KWh or thereabouts and produce about 700 KWh with the biggest gap near the solstice in December (due to the very short days). It is simply not feasible to bridge that gap with batteries and we also consume about 450 cubic meters of gas per month in that period, which for a house this type and size is actually pretty good.
So I don't buy the 'personal autonomy' argument unless you want to cut your winter consumption to ~30% of your summer consumption, set your house to 14 degree room temperature (in many households that would be grounds for divorce) or get a 500 KWh battery system, which would set you back approximately $300K at the best prices that I can find today. I don't think that's worth it.
Everything depends on where you live. But for any country more than a few degrees off the equator that's the reality.
> Regarding personal autonomy, I wouldn't treat it as this binary thing.
That's fair, but 'personal autonomy' for 70% of the year and utterly dependent on existing infrastructure and fossil fuels for the remainder is still bad. But better than 100% dependency, sure.
> If you're survivalist minded, solar is your only hope at any level of independence, even if it's not 24/7 autonomy.
Depends on where you live ;)
Seriously: I engage in engineering, not in satisfying paranoia and 'any level of independence' starts with ruthlessly curbing your energy budget below that which most Western countries' inhabitants would consider acceptable living standards. And even if I personally would be ok with that I don't see how I would make that decision for myself while at the same time not make that decision for those around me who depend on me for their needs. In a vacuum you can make that argument, but IRL people don't live in a vacuum.
No man is an island.
In an extreme situation when you have no grid for a week then yes, having to slum it by only heating one room.
Every house having 50kwh would allow massive grid smoothing when wind and solar are fluctuating. Just one day of storage would allow a lot of arbitrage, but when power is cheap overnight and run solely off battery when it’s expensive.
With solar panels that can fill it up daily (eg. blackstart)?
And it's in much of Europe where a village or a few villages being without power for a day or more is headline news.
No, we were way ahead of our efficient house here in Europe because we were able to design that efficiency right into the structure. That house sipped power and the heater ran off the damaged trees on the property that we cleaned out annually.
I kept pretty careful logs of consumption before pulling the trigger on going off-grid and it's interesting to see how the reduction in consumption factored as much into that as the increase in renewable energy. Once the windmill was added the generator basically never ran again.