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Comment by jules | Hacker News Reader

Batteries are so expensive that it is unclear whether they will ever solve the large scale storage problem: yes they're getting cheaper, but they have to continue to get cheaper for a long time before they're suitable, and it's unclear whether fundamental limits will be hit before that. If battery technology improves to the extent that it becomes viable for large scale storage, then wind and solar can become our main source of energy. Until then, nuclear is the only proven solution. Betting on batteries now amounts to gambling with the planet.

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Batteries are not supposed to solve the large scale storage problem. They're best at solving the small scale storage problem. Recently they solved the problem of small scale storage on wheels.

> If battery technology improves to the extent that it becomes viable for large scale storage, then wind and solar can become our main source of energy.

Batteries are not the only way of storing electricity.

First thought I had here was hydroelectric storage.

Especially after that prospective sites research by the Australian National University (https://www.anu.edu.au/news/all-news/anu-finds-530000-potent...), that seems like a reasonable choice.

Battery backed solar/wind is cheaper than nuclear these days.

It's not been that way for long though. Economic grid scale batteries are here but still relatively new.

It makes sense to continue running old nuclear plants but not to build new ones. Much too expensive.

Is it? Are you taking into account battery degradation from 1 cycle every day? The vast majority of battery chemistries won't last more than 3-4 years under those circumstances, and those that would are either much more expensive or experimental.

As of now storing 10kWh at 1kW costs around 1000$ from the cells alone. If you're changing them every 3 years then you have to spend 10 000$/kW over 30 years whereas nuclear is the same price per kW for a 30 year period.

If you don't take that into account then sure.

Aren't lifetimes closer to 10+ years due to better battery management (managed operating temperature and charge/discharge)?

Tesla suggest such with its megapack https://en.wikipedia.org/wiki/Tesla_Megapack

Only if you don't do daily ~80% discharges.

You can avoid that right now because the grid has baseload. But if it doesn't you can avoid the wear cycles.

10 years is about what you'd expect if you only discharge ~30% of capacity daily, which is how it is operating right now.

This suggests it's even cheaper than gas now:

https://www.spglobal.com/platts/en/market-insights/latest-ne...

And gas is a lot cheaper than nuclear.

Theres a new battery backed solar plant in california that can service the early evening peak times with cheaper electricity than coal.

Battery prices have been plummeting consistently for the last three years.

> battery chemistries

Ah, you're focused on chemical batteries.

Hauling a lot of water up a mountain at times of low demand, and releasing it through a turbine at times of high demand, is a type of battery; it seems to me a reasonable approach to smoothing supply and demand for wind/solar.

I agree that it's going to be a long time before grid-scale chemical batteries can help much with demand-smoothing.

I'm focused on chemical batteries because that's what's being talked about when people say battery.

Pumped hydro is promising but it's going to be as expensive as regular hydro.

Probably.

I'll point out using existing natural gas peaking plants to make up for temporary shortfalls of solar and wind power is also a viable stop gap.

The latest US plan aims for a 95% carbon free grid by 2035. They could have aimed for 100%, but it's cheaper to start electrifying more things at that point, as 95% carbon free electricity powering a heat pump is better than burning gas for heat. They therefore get the eqivalent of 105% carbon reduction for the same cost, more than they'd get by focusing on the final 5% of carbon on the grid.

As far as I know, few people suggest (Lithium-)batteries for long term storage. Electrolysis, optionally followed by turning the Hydrogen into Methane, seems like a much more scalable solution. That works at scale today, it's just too expensive to make sense at this point. Then there are other types of batteries that might become much cheaper in the future, perhaps redox-flow batteries or something like that.

According to people I talked with, who did analysis for "Green hydrogen" as storage method, assuming Poland - we would need something along the line of 150% peak production, locally, before it started moving the needle at all - and I'm not sure of this wasn't in combination with nuclear (though limited by the idiotic free market on electricity).

All of that assumes that the demand doesn't go up... Which is not compatible with things like climate goals

Hydrogen, molten salt to drive ex-coal plants, redox-flow, …

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