14 hours of battery (~40 TWh for China) with the hydrogen storage or without? Because the calculator was reporting ~78,000 GWh battery storage with China's weather selected, and 2030 technology assumptions. I changed the spatial capacity factor from 1 to 2 and the battery storage requirement dropped down to 68 TWh, but still well above 40 TWH.

Regardless, 14 hours of China's electricity demand is a whopping 40,600 GWh. By comparison, 2024's lithium ion battery production figure was 1.5 TWh [1]. Even assuming 100% of this went to EV's we're still talking about roughly 25 years worth of global battery production to fulfill only China's demand for storage in this model. As you point out, we still have loads of battery demand for EV adoption, so nowhere near 100% of production will be able to be diverted to grid storage.

The scale of storage required to make intermittent sources viable without being backed by a dispatchable energy source really is tremendous, and this often gets overlooked in pushes for a fully renewable grid.

1. https://www.argusmedia.com/ja/news-and-insights/latest-marke...

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epistasis 4 hours ago | parent | next [-]

Battery production capacity grows by 10x every five years. It was four years ago when I first heard that, and we are exactly on track still. In 2031 we will be at 20-30 TWh/year production capacity.

There are few things that grow this fast when it comes to manufactured things, atoms are far harder to arrange and scale than bits. But it's happening at a tremendous scale. Natural gas turbine production capacity is tapped out with long order queues, and so is battery production well into 2026, but only battery production capacity is expanding at breakneck speed.

	▲	Manuel_D an hour ago \| parent [-]
		Understand that only ~6 TWh of lithium batteries have been produced to date. As in, every single year of production combined adds up to less than 6 Twh. Moore's law largely stemmed from the fact that making a processer faster also meant making transistors smaller. Reducing the width of a transistor to a half, a quarter, etc. increased compute per cm^2 by double, quadruple, etc. Chemistry doesn't obtain that kind of exponential growth - we have hard limits on the number of joules we can store per gram of anode and cathode, so scaling up production means digging up more anode and cathode material out of the ground. The nature of resource extraction is that the easiest-to-exploit reserves are exhausted first, and continued production is contingent on accessing the progressively more and more inconvenient reserves. Maybe in 2030 annual global production will be 30 TWh - we'll know in 4 years. But there's a lot of people who probably don't want to make trillion-dollar investments gambling on that possibility panning out. Regardless of your confidence in battery production's continued growth, I think you'd agree that if someone is making a calculation about the required amount of overproduction required to maintain a stable grid, they should at least mention that their calculation is contingent on provisioning tens of terawatt hours worth of grid storage.

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nicoburns 7 hours ago | parent | prev | next [-]

I wonder what proportion of energy use goes towards either heating or cooling and could use a thermal energy store rather than an electrical one.

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pfdietz 8 hours ago | parent | prev [-]

That was about the amount in both cases. Slightly more in the no-hydrogen case than otherwise. Hydrogen contributed only marginally.

Yes, it's a lot of batteries. So what? It's not like the current battery production is some firm limit. If anything, the very large future demand ensures batteries will be driven down their experience curve, so the cost will be even lower than assumed.

The world spends something like $10T per year on energy. Any replacement energy system is going to be a big thing.

You need to make an argument that is more than you expressing fear of large numbers.