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U.S. battery storage capacity to increase significantly

eia.gov

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Re: U.S. battery storage capacity to increase significantly

#41

Post by jupp0r »

kevinventullo wrote: post #11
crmd wrote: post #3

> Developers and power plant owners plan to significantly increase utility-scale battery storage capacity in the United States over the next three years, reaching 30.0 gigawatts (GW) by the end of 2025 Can someone explain how/why they are measuring storage capacity in watts?

This doc has more information: https://www.nrel.gov/docs/fy19osti/74426.pdf They’re talking about the power capacity , which is the maximum instantaneous rate of discharge as measured in kW, as opposed to the energy capacity which is measured in kWh. From what I can glean, it appears that for many applications, the power capacity is actually the more important number.

If this was true, we'd be building capacitors instead of batteries...

Re: U.S. battery storage capacity to increase significantly

#42

Post by cptskippy »

jupp0r wrote: post #41
kevinventullo wrote: post #11

Earlier quoted context omitted.

This doc has more information: https://www.nrel.gov/docs/fy19osti/74426.pdf They’re talking about the power capacity , which is the maximum instantaneous rate of discharge as measured in kW, as opposed to the energy capacity which is measured in kWh. From what I can glean, it appears that for many applications, the power capacity is actually the more important number.

If this was true, we'd be building capacitors instead of batteries...

Or perhaps your understanding of the problem is incomplete?

The point of the batteries are to store power when it's cheap and abundant, then deliver it during peak demand for sustained periods. The time between those periods is measured in tens of hours.

Re: U.S. battery storage capacity to increase significantly

#43

Post by bobthepanda »

blamazon wrote: post #36
bobthepanda wrote: post #18

Earlier quoted context omitted.

It's worth noting that pumped hydro, and the dams that are getting torn down for environmental these days, often look very different. Usually the dams that are getting torn down, block the entire river, and thus fish from passing up or downstream of the dam. (Fish ladders exist but are not particularly effective.) Pumped hydro may sit by the side of a river, but otherwise not obstruct the flow, and so that is not a m…

Huh, that is a really important point, and totally changed my perspective on pumped storage projects. Very cool, thanks for sharing.

Also, pumped storage tends to be smaller, in that it’s meant to provide a certain level of discharge for hours or days. So the reservoirs can be a lot smaller.

Re: U.S. battery storage capacity to increase significantly

#44

Post by zizee »

algo_trader wrote: post #14
zizee wrote: post #5

Earlier quoted context omitted.

Context for your context: Bath County resevoir is descrbed as "largest battery in the world", and cost the equivilent of 4 billion dollars (in 2021 $), occupies 265 acres of land, and has a capacity of around 14,000,000 m3 of water. I'm curious to see how the costs compare. My understanding is pumped hydro storage gets cheaper at scale. If my math is correct, 24GWH of storage at $4 billion dollars^ is $167 per kilowa…

Pumped hydro can amortize over 50-100 years. In a true renewable grid, you will get over 50,000 cycles from the same dam (with some turbine replacements). EDIT: numbers..

How much labour is involved in the upkeep/operation vs a battery bank?

I think that there are pros and cons of each, we'll end up with a mix of lots of different solutions.

Re: U.S. battery storage capacity to increase significantly

#45

Post by jupp0r »

cptskippy wrote: post #42
jupp0r wrote: post #41

Earlier quoted context omitted.

If this was true, we'd be building capacitors instead of batteries...

Or perhaps your understanding of the problem is incomplete? The point of the batteries are to store power when it's cheap and abundant, then deliver it during peak demand for sustained periods. The time between those periods is measured in tens of hours.

So your point is that we care about energy storage capacity more than about maximum discharge power after all?

Re: U.S. battery storage capacity to increase significantly

#46

Post by nl »

jupp0r wrote: post #45
cptskippy wrote: post #42

Earlier quoted context omitted.

Or perhaps your understanding of the problem is incomplete? The point of the batteries are to store power when it's cheap and abundant, then deliver it during peak demand for sustained periods. The time between those periods is measured in tens of hours.

So your point is that we care about energy storage capacity more than about maximum discharge power after all?

Of course we care about the energy amount stored - some. But total power capacity is more important for a large number of applications.

The usage the OP listed (arbitrage) is only one of the 9 function listed by the National Renewable Energy Lab[1]. Many of the functions need immediate power capacity in the seconds to an hour (so MW seconds or MW minutes), and more important is the speed of response and the amount of power deliverable.

[1] https://www.nrel.gov/docs/fy19osti/74426.pdf see table 1

Re: U.S. battery storage capacity to increase significantly

#47

Post by nl »

tromp wrote: post #35
epistasis wrote: post #29

Earlier quoted context omitted.

Are you saying that you can't measure battery power capacity? Why would you assert something weird like that? Grid assets are measured by power, and power is a key specification of storage capacity. Edit in response to your edit: the EIA, and in fact all the people who run grids and the grid storage, refer to capacity in terms of power, and when talking about "storage capacity" on the grid continues to use power beca…

> Grid assets are measured by power That seems of limited use without knowing for how long the power can be supplied. 1GW for 1 second is pretty useless. 1GW for a minute not much better. Most people would say that 1GW lasting a day is more storage capacity than 10GW lasting only an hour. Wouldn't batteries optimized for power take the form of supercapacitors [1] instead? [1] https://en.wikipedia.org/wiki/Supercapaci…

"Seconds" of capacity might be useful for "primary frequency response" but not for any of the other functions listed in table 1 of https://www.nrel.gov/docs/fy19osti/74426.pdf. Primary frequency response is only seen as important in a limited number of markets in the US (see that table).

Re: U.S. battery storage capacity to increase significantly

#48

Post by jupp0r »

nl wrote: post #46
jupp0r wrote: post #45

Earlier quoted context omitted.

So your point is that we care about energy storage capacity more than about maximum discharge power after all?

Of course we care about the energy amount stored - some. But total power capacity is more important for a large number of applications. The usage the OP listed (arbitrage) is only one of the 9 function listed by the National Renewable Energy Lab[1]. Many of the functions need immediate power capacity in the seconds to an hour (so MW seconds or MW minutes), and more important is the speed of response and the amount of…

You are describing perfect use cases for large capacitors, which was my point earlier.

Re: U.S. battery storage capacity to increase significantly

#49

Post by lazide »

epistasis wrote: post #40
lazide wrote: post #37

Earlier quoted context omitted.

It is a bit weird, and seems to come from a history of fossil fuel, nuclear, and/or hydropower where the total capacity is always some (very large) multiple of the instantaneous power level. With storage currently just supplementing other power sources as renewables aren’t the majority (or all) of available capacity to provide grid stability, it makes sense I guess. None of these battery storage systems need to provi…

"Long duration" storage doesn't have many economic use cases right now, unless the cost is a tiny tiny fraction of current storage costs. There are many startups developing tech for this, and one with the most hype (and the one I'm most excited about) is Form Energy, which is using iron-air chemistry. Nonetheless, I do not expect to see a significant market demand for such batteries until into the 2030s; it takes a r…

I agree, thanks for writing that up.

Do you think it will require the phase out of things like Natural Gas peaker plants to make longer term storage more worthwhile?

Off grid, the most economic setup right now in California is essentially solar + batteries with battery storage sized up to about a day/24 hrs of load, with a propane fueled generator + propane backup heaters for ‘emergencies’ like long winter storms.

Generators get exercised regularly to ensure functionality, but otherwise don’t get run unless needed, which is rare. Maybe 16-24 hrs a season. They also charge the batteries when their full load isn’t needed elsewhere, which cuts run time.

Natural Gas would of course be the replacement for propane in a grid situation, where it was available.

The paperwork and permitting in general is a sign of the future for sure. sigh

Re: U.S. battery storage capacity to increase significantly

#50

Post by epistasis »

lazide wrote: post #49
epistasis wrote: post #40

Earlier quoted context omitted.

"Long duration" storage doesn't have many economic use cases right now, unless the cost is a tiny tiny fraction of current storage costs. There are many startups developing tech for this, and one with the most hype (and the one I'm most excited about) is Form Energy, which is using iron-air chemistry. Nonetheless, I do not expect to see a significant market demand for such batteries until into the 2030s; it takes a r…

I agree, thanks for writing that up. Do you think it will require the phase out of things like Natural Gas peaker plants to make longer term storage more worthwhile? Off grid, the most economic setup right now in California is essentially solar + batteries with battery storage sized up to about a day/24 hrs of load, with a propane fueled generator + propane backup heaters for ‘emergencies’ like long winter storms. Ge…

Last I heard, lithium ion is cheaper than the OpEx for the average existing natural gas peaker, but I haven't checked in a year or two. With the fluctuating cost of gas, and the recent small rise in battery cost from supply constraints, I could see that flipping back and forth. And there will be a long delay between having a new cost king and a switchover due to utilities being able to charge rate payers for stranded capital, and also the generally slow utility process for developing new resources, which is often on a five year time scale, using decisions made on five year old data.

That's pretty exciting with regards to off-grid use, I don't know much about it. 24 hours of fossil gas use per season is just absolutely tiny, one could definitely even imagine synthetic fuel production from electricity and air being enough to generate that. Thanks for the info!

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