> It would probably help to show the working here: Fair enough, I was on mobile. According to https://en.wikipedia.org/wiki/World_energy_supply_and_consumption

> It would probably help to show the working here: Fair enough, I was on mobile. According to https://en.wikipedia.org/wiki/World_energy_supply_and_consumption#Final_consumption https://en.wikipedia.org/wiki/World_energy_supply_and_consum..., the world consumed 9,717 Mtoe or 112,717.2 TWh of energy in 2020. Dividing that number by 52 weeks/year gives us 2,167 TWh--the amount of energy we need for a week's worth of storage. 2,167 is about 3612 times the amount of capacity that Europe is slated to produce annually (previously I rounded various figures before doing the math, so my number rounded up to 3700 rather than down to 3600). But as previously mentioned, this doesn't account for growing energy demands or wear on battery stock or many other pertinent factors. > First, we will occasionally want them to last a week; most of the time you’d only want a day. This gives us longer to build out whatever solutions, more battery factories or reactors or whatever. My "week" figure is based on the assumption that we need to be able to manage with near-zero wind/sun for a week. While most of the time you won't need a week, we're not concerned about "most of the time", we're concerned about the worst cases. By the way, I have no idea if a week is accurate. I've just heard "weeks" slung around, so I assume that "one week" is the low end. I would be surprised if we could get this down to a day on average. Mind you, this doesn't mean we need 1 week of storage, but it means we need 1 week of something besides solar/wind. > Second, it is very plausible the non-linearity of scaling will reduce costs rather than increase them I agree. The specific dynamics depend on the market and the supply chain, but I'm pessimistic, especially after seeing the havoc covid continues to wreak on supply chains the world over. > Third, my personal favourite combo with batteries is intercontinental HVDC This is really interesting. I always been a bit surprised that electricity isn't more fungible from region to region, and wondered why this was never really talked about as a serious mitigation against regional weather patterns. I've been thinking about clean energy as Europe's key to energy independence, but it would be cruelly ironic if Europe came to depend on simply a different region for its energy (and also for Africa, if its sunshine had the effect that oil tends to have on poorer countries).