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Do you have evidence that batteries are cheaper than say nuclear? I only heard of the opposite, batteries are prohibitively expensive.

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Until recently, batteries have been very expensive. However, like wind and solar, as we build the industry they are dropping exponentially in cost, at about 20% per year over the past decade [1], and we are hitting a non-linear inflection point when it's more profitable to include batteries in a new build than to omit them.

One set of estimated from Lazard: advanced nuclear at $118-$192/MWh, and lithium-ion charged from directly attached solar at $102-$139/MWh [2].

Lazard have analyses for energy generation costs by technology, and storage costs based on use case and scenario. (Note that the storage use cases include the cost of charging the storage system.)

These cost estimates work hard to simplify a hugely complex subject, by estimating a levelized cost of energy, which is then of course an oversimplification. It doesn't consider the value of when energy is delivered, or the price of when the storage is charged. EIA, filled with a lot of hard energy guys that are dismayed to see renewables outperforming in cost, puts out ridiculous numbers, but has also embraced something called the LACE to try to compensate. However they have been so wrong on hard numbers that they can't be trusted when it comes to renewables.

The design of energy markets has absolutely huge impacts on the profitability of storage as well, and it can still be very hard to get compensated for the value provided to the grid. There probably would already have been GW of batteries on Texas' ERCOT grid if they buy/sell dual nature had been legal earlier.

[1] https://arstechnica.com/tech-policy/2020/09/the-story-of-che...

[2] https://www.lazard.com/perspective/lcoe2019/

Batteries are only the most of expensive of many candidates for energy storage.

But, as was demonstrated in Australia, adequate.

Australia has a tiny (on grid scale) battery used to stabilize the grid, not for long term storage like you would need for relying on solar energy in place that actually has winters.

> Batteries are only the most of expensive of many candidates for energy storage.

Maybe. But nuclear does not require batteries.

> But, as was demonstrated in Australia, adequate.

I do don’t have the numbers from Australia at hand. Do you? Is it really cheaper than nuclear, or they heavily overpaid for them, or Telsa sold it with large discount?

I love that Australia battery, but lets be real its tiny. Comparing that to a solution that could fully balance all solar/wind energy is a gigantic strech.

I have looked into all of these storage mechanism, and not one is actually really read for the market and is mass deployable quickly.

We just have to hope Tesla can actually spit out many tera of batteries by 2030 and the other companies match them.

But only adequate for a very narrow use-case so far, _not_ as a daily driver.

Here in South Australia where I live the Hornsdale installation (the Tesla one) is capable of storing 150MW. Its purpose is not to drive the entire grid every day, but to help deal with minor fluctuations in supply and demand, and mitigate brown/blackouts during emergencies. In-between those times it stores electricity while prices are cheap, and sells when the prices are high to turn a profit

The overwhelming source of electricity across Australia is supplied by fossil fuels (despite our abundance of clean nuclear fuel).

The entire reason the installation was built in the first place was because of a series of brownouts and blackouts caused by interruptions in the supply of electricity from interstate one day (we don't generate enough by ourselves sadly). It caused a fairly large political situation to develop, and resulted in the construction of the Hornsdale installation.

Contractually Hornsdale is obliged to be able to supply 70MW for 10 minutes, or 30MW for 3 hours on demand during emergencies. For some perspective, the current load on the grid as at the time I started writing this is 2150MW(6pm local time).

Australian battery installations are simply not operating at the scale you want them to be here. Hornsdale has a niche it is filling quite admirably, but be careful when you use it as an example of grid-scale viability. It's simply not.

One potential alternative to batteries might be to build a couple of towers lifting concrete blocks up and down: https://energyvault.com/#operating-parameters

I'd heard of this as a theory many times before, I didn't know someone had actually built one! Good site too, thanks for the link.

I’m not sure this idea is all that they’re marketing it as.

Here’s a video discussing the drawbacks [0], the guy doing the video can be kind of abrasive at times but worth watching/skimming as a counterpoint.

[0]: https://youtu.be/NIhCuzxNvv0

My research into this a little while ago showed that this has a very poor energy density to capital cost. There are some other techs like molten salt which are supposed to be better.

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