What solar storage technologies work in the winter? For instance, it has been rainy in California this year, and between Jan and March, we were at a production deficit of 1MWh for our house. So far, in May (so the last 5 days) we’re at a 275KWh deficit, and every day has seen a deficit so far.
I’d love to have a 1MWh battery, but current raw battery cost is $151/KWh, and actual residential systems are closer to $333 to $666 / KWh installed. At the raw battery cost (ignoring space requirements!), we’d have already burned through $41,000 of battery capacity this month, and the weather forecast suggests we’d need double of that to get through till wednesday. That’s $82K for raw batteries, or $275K at the midrange for residential installs (ignoring solar costs). Grid-scale storage is somewhere between those two numbers, and this is May. Winter this year was even more unworkable.
Small-scale solar installations are not supposed to get you off-grid and like you observe, a small-scale/battery storage isn't going to change that.
Instead, the idea is the grid-scale combination of solar, wind and hydro with various storage and adaptive consumption solutions. For example: when water levels are down, pump water up the dam during sunny/windy hours to store energy for the bad months.
Normal hydro is failing due to climate change (at least in the US west), so that’s not a great bet to make.
Nuclear is maybe 2-3x more than renewables at this point, but that’s actually a pretty good deal, given its safety record vs literally everything else.
Of course, it’s best to produce as much as possible with cheap wind, solar, and battery, but getting from 80% to 100% means over-provisioning to the point where nuclear would be cheaper.
That's part of the point: pumped storage (and other solutions) can be used even though the climate changes. Batteries won't have to be the main storage solution.
Another part: over-provisioning does not increase the costs much as there will be flexible demand for the additional electricity produced.
I’d love to have a 1MWh battery, but current raw battery cost is $151/KWh, and actual residential systems are closer to $333 to $666 / KWh installed. At the raw battery cost (ignoring space requirements!), we’d have already burned through $41,000 of battery capacity this month, and the weather forecast suggests we’d need double of that to get through till wednesday. That’s $82K for raw batteries, or $275K at the midrange for residential installs (ignoring solar costs). Grid-scale storage is somewhere between those two numbers, and this is May. Winter this year was even more unworkable.