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0 pointsmdorazio5y ago0 comments

We do have a good way to store energy. It's called batteries, they are already cost effective in several use cases, and their cost is going down about 5% per year.

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throwaway8943455y ago· 2 in thread

Critically, batteries aren't cost effective for the use case in question: storing solar and wind energy in a world where these are the primary energy sources. They're going down 5% per year, but who knows how long that trend will hold, especially if we're talking about a wide-scale switch to unreliable power sources (driving up the demand for batteries).

I want to live in a world powered by solar and wind, but we can't just wish away the reliability issues. And I don't think we should keep burning fossil fuels while we chip away at the storage problem. And we don't have to--we can build nuclear plants while we work on the storage problem.

As an aside, I think it would be really cool if something like Energy Vault (https://energyvault.com/) could be the solution (at least for the majority of use cases); however, I have no idea how feasible it is.

socialdemocrat5y ago

I have played around with a simulator for this. Wind and solar is so much cheaper than nuclear power that you can simple build a lot of overcapacity to deal with much of the storage issue. Wind almost never go to zero during a year.

For the rest of the time you just use gas power plants. According to my calculations I could get lower kWh price than with nuclear and only provide 10-20% of the power from natural gas.

We can run on 10-20% natural gas for a while until we develop better storage.

Andrew_nenakhov5y ago

> Wind and solar is so much cheaper than nuclear power

Could you please cite a source for this extraordinary claim?

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Manfredo_15y ago

The US has about 8 seconds worth of battery storage. By comparison, to use renewables for 80% of our electricity we would need 12 hours of energy storage. For 100%, 3 weeks of storage [1]. 1 hour of energy storage in the US is 500 GWh. This amounts to more than the sum total of global lithium iron battery production (currently about 300 GWh) [2].

1. https://pv-magazine-usa.com/2018/03/01/12-hours-energy-stora...

2. https://www.nextbigfuture.com/2020/02/world-battery-producti...

adrianN5y ago

Don't oversell them. Batteries as they are today are much too expensive to cover all needs. You need a way to store weeks of power consumption for large areas. Batteries are too capital intensive for that. They can take the role of peaker plants, but they are currently unsuited for storing energy for dark, windstill winter weeks. For that other technology, for example Power-to-Gas is needed currently.

V6HBGNQHU5y ago

When people talk about the cost of solar they ignore the price of batteries and underestimate the amount of batteries required. Watch this video about renewables in California[0]. The video mentions a study that would put the cost of energy storage required for California to be 100% on renewables would be over $3.6 trillion which is equivalent to an entire year's GDP for the state. The video author explained that study's methodology got that number by assuming enough to store excess capacity during the summer to provide power in winter when not enough would be generated on most days. This isn't great because li-on batteries are not great for long term storage and would lose power over time.

[0] https://www.youtube.com/watch?v=h5cm7HOAqZY

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