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Comment by brutusborn | Hacker News Reader

It's not critical, but I think you are looking at the wrong page. $55 is on the /MW basis, the next page shows $131/MWh which is still good.

The source is "Lazard estimates", but I can't find anything close to this in reality. Pumped hydro is meant to be super cheap, but is currently ~ $100/kWh. I'm starting to agree with the other commenter that Lazard is bunk.

"Pumped hydro is already the cheapest energy storage technology in the world in terms of cost per installed kilowatt-hour of capacity. Total project costs range between $106 and $200 per kilowatt-hour, compared to between $393 and $581 for lithium-ion batteries, World Bank figures show." https://www.greentechmedia.com/articles/read/pumped-hydro-mo...

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Its not bunk. People are comparing two widely different things and not understanding the difference.

The price of $150 is capacity of a battery. If i want a battery that can store 4 kwh i pay $600.

The other number referencing $55/MWh is referencing levelized cost of storage. I have a a MWh but instead of using it right now i store it for 4 hours. Now this MWh costs its initial price + $55.

Apply this example to a KWh where i would pay $0.1 for it if i used it right now if i want to store it for 4 hours and use it later i have to add $55/1000 to the price or about $0.055. So a directly used KWh would cost me $0.1. One stored for 4 hours would cost me $0.15.

Hope that makes sense and explains these different numbers.

I think I understand... are you essentially saying the 150 is capex and 55 is opex?

Lazard is generally regarded as pretty credible.

BloombergNEF says $145-167 per MWh.

> If you do that calculation at the global level, we evaluate the LCOE for recently financed projects is at US$150/MWh including charging costs. That’s our benchmark. We have a range around that benchmark which goes from US$115/MWh in China.

https://www.energy-storage.news/behind-the-numbers-the-rapid...

Thanks for the link. I am trying to get my head around the ~1000x improvement and I think it is because we are comparing apples and oranges. ~$100/kWh (like pumped hydro) can last for as long as the water in the reservoir lasts. ~$100/MWh (like the batteries you mentioned) are for <4 hrs reserve.

So the critical question is: how long will grids connected to renewables need reserve? 4 hours doesn't seem like much but I'm not sure the best way to find this info. Edit: from a 30s google search, 4 hours is only good for <80% renewables in Aus. [0] https://reneweconomy.com.au/much-storage-back-high-renewable...

80% renewables is huge! It's some years before we get to that level by which time we can expect the 20 hours required for all states to be economically viable.

And in the mean time gas peaker plants provide a viable, cheap and safe compromise without needing nuclear!

> We found in some cases the battery requirement becomes very large relative to the load, at greater than 20 hours. In these cases, it was concluded that additional gas peaking capacity would be more economic (and biogas was used when the emission constraint did not allow for natural gas).

This is the original report: https://www.energynetworks.com.au/resources/reports/electric... and these graphs are on page 98.

Yeah, we can use gas plants until batteries become economical, but why use gas when we could start the switch to a low-emission alternative now. The risks of Nuclear are tiny compared to the existential risks of delaying emissions reductions.

Biogas use isn't practical to replace existing gas supply.

I honestly really wish renewables + batteries could take over but it's too early. Aus has heaps of Uranium, is geologically stable, has strong regulating authorities and geopolitically secure. The perfect spot for low-emissions Nuclear which is practical and possible now in all respects except for politically.

>Lazard is generally regarded as pretty credible.

No they're not, as already pointed out in response to your other comments (e.g. https://news.ycombinator.com/item?id=32092280), yet you continue to cite them as an authority.

Not to mention the other comments that refute those numbers using the same paper - projects would be closer to ~$100/KWh when storage is taken into account, as shown graphed in the paper itself.

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