In Australia, the real value of these big batteries is not necessarily to provide emergency power, but more to respond in milliseconds to variations in demand and to smooth out the 5 minute spot market.
Having a sink and a source for spikes aids grid stability and somewhat helps to reduce the need to build more infrastructure to handle transmitting power from the generators during those peaks.
It also helps avoid the viability of gas powered generators which are very expensive and carbon intensive.
I'm glad they're reporting it as the energy storage capacity and not the power output capacity. Too many news sites like to report the power output capacity in stories like these, which is horribly misleading, and then often they also frame it as though this is equivalent to adding actual power generation to the grid, which is even more misleading.
One reason they report in MW instead of MWh, is that grid operators primarily spec systems by their continuous MW, and only secondarily mention their cumulative MWh. So that's the way they talk about them, and reporters just mimic that. Both are important, but the top-line number is MW, for sure.
One reason for this is that for a lot of grid-support functions, instantaneous or short-term power is vastly more important than long-term energy capacity. The other reason is that traditional generation is only sized by MW; you just keep pouring fuel into it forever, so the notion of MWh doesn't even enter the picture. They're not even thinking in those terms.
You and I, as battery natives, think about it the other way around. But we're not grid operators.
It's probably also a view that is shifting as batteries move from primarily providing short-term grid stability (where power available is probably the more important metric) to longer term storage.
Having worked in the industry for a bit, the reason people talk about "MW of batteries" is because they're usually designed to deliver the capacity for a fixed number of hours. Earlier batteries would do 1 hour (so a battery would typically be 1MW/1MWh) and newer sites coming online are usually 2 hours (so 1MW/2MWh). As battery deployment grows the money is increasingly just in energy arbitrage, so there's a lot of pressure for longer duration storage. If you see a headline MW figure it's a safe bet that it's between 1-2x that in MWh.
I can see why one might intuitively think this, but actually this is just a bad take. For most practical purposes, the main value added by these batteries is not really the size of their storage capacity (afterall, their capacity is tiny relative to the grid's needs), but their ability to quickly sink or supply massive amounts of power.
If these batteries had 10x the storage capacity, but 1/10th the power output, they'd miss out on their biggest advantage, which is capturing mid-day solar oversupply, and providing virtual grid inertia.
Long duration, lower-power batteries will have an important role to play once grids get further along in renewable adoption, but for now, short duration power-supply is the main value they add, and it makes perfect sense to quote battery numbers in terms of power. (not that I'd complain about providing capacity numbers too)
Makes sense. With battery technology improving and being the cheapest it's ever been, why not? This is probably the direction most countries will go in the future.
So if ALL power generation of the US would stop right now, EVERYTHING would still have power for 25 minutes. (ignoring all safeties tripping, and perfect load balancing)
No. Because neither storage nor generation is evenly spread. In some places you would have nothing, in some you could have potentially hours.
In practical terms, you would most probably get nothing, because situation like this would lead to complete grid breakdown and interruption of service.
Technical detail question: if all of those batteries were on connecting allowing feeding back to the grid, would they be able to synchronise the frequency/phase? What's the threshold/requirement for that to happen?
Only if that battery was connected to 500GW of inverter capacity (and the grid was a spherical chicken -- enough intertia-replacement devices to keep timing working, enough capacity to link supply with demand etc)
Grid batteries was one of the few areas that escaped Trumps gutting of the IRA and was included in other Infrastructure bills.
And a side effect of the EV market getting hobbled also redirected battery factory capacity from that market.
I'm not sure what's online yet but there is a pipeline.
edit an estimate from earlier this year:
> By the end of 2025, 20 gigawatt-hours of dedicated storage cell lines had opened, and the industry is on pace to hit 96 gigawatt-hours by the end of this year.
It's nice to see more storage being added, but we have keep thr order of magnitude in mind: the peak electricity demand for the US is 750GW, so the added storage for the past 3 month corresponds to just 96 seconds of peak consumption.
Obviously there are a variety of sizes and configurations, but if you assumed 3.5MWh per 20ft container, that's 5771 containers, and if you assumed a PCS container per two battery container, that's 8656 containers, just for an idea of the scale.
I've always wondered why they don't stack them in deployment -- the containers are obviously fine with it! -- but I guess land is cheap enough not to bother.
Horizontally they need plenty of room for airflow, as each container has some HVAC-or-whatever module on the side. But vertically...
> I was snobby and looked up the numbers because I didn't think this is relevant. But it is.
Kudos to you for bein' "that guy". So many folks sit and comment while having the world's biggest library of information on just about every topic right there at their fingertips and still can't be bothered to take the 30 seconds to look up something they don't know about on their favorite search engine. I appreciate you for havin' done "the right thing" here. :)
- The utility-scale market continued underpin growth, with 18 GWh installed, largely supported by seven gigawatt scale projects. Arizona installed over 6.2 GWh of utility scale projects, the largest quarterly deployment for any state in history.
- In the BTM space, residential storage added 657 MWh and commercial and industrial (C&I) added 1.8 GWh, largely on the back of demand from data centers.
There's likely some spare solar capacity that will help. Currently the peak of solar is almost counterproductive, but converting that to storage is good for both the consumers and the power plants. (Less feed in during the day, lower evening peak)
As far as I know, we have yet to figure out how to capture power from a lightning strike. There is a lot of energy there, but it's static electricity which is completely different from what any grid runs on.
yea, i think the low efficiency (plus how to predict where lightning would hit!). Might as well just put up a wind turbine, since wind is much more predictable, not to mention easier to harvest.
In Australia, the real value of these big batteries is not necessarily to provide emergency power, but more to respond in milliseconds to variations in demand and to smooth out the 5 minute spot market.
Having a sink and a source for spikes aids grid stability and somewhat helps to reduce the need to build more infrastructure to handle transmitting power from the generators during those peaks.
It also helps avoid the viability of gas powered generators which are very expensive and carbon intensive.
I'm glad they're reporting it as the energy storage capacity and not the power output capacity. Too many news sites like to report the power output capacity in stories like these, which is horribly misleading, and then often they also frame it as though this is equivalent to adding actual power generation to the grid, which is even more misleading.
One reason they report in MW instead of MWh, is that grid operators primarily spec systems by their continuous MW, and only secondarily mention their cumulative MWh. So that's the way they talk about them, and reporters just mimic that. Both are important, but the top-line number is MW, for sure.
One reason for this is that for a lot of grid-support functions, instantaneous or short-term power is vastly more important than long-term energy capacity. The other reason is that traditional generation is only sized by MW; you just keep pouring fuel into it forever, so the notion of MWh doesn't even enter the picture. They're not even thinking in those terms.
You and I, as battery natives, think about it the other way around. But we're not grid operators.
It's probably also a view that is shifting as batteries move from primarily providing short-term grid stability (where power available is probably the more important metric) to longer term storage.
Having worked in the industry for a bit, the reason people talk about "MW of batteries" is because they're usually designed to deliver the capacity for a fixed number of hours. Earlier batteries would do 1 hour (so a battery would typically be 1MW/1MWh) and newer sites coming online are usually 2 hours (so 1MW/2MWh). As battery deployment grows the money is increasingly just in energy arbitrage, so there's a lot of pressure for longer duration storage. If you see a headline MW figure it's a safe bet that it's between 1-2x that in MWh.
I can see why one might intuitively think this, but actually this is just a bad take. For most practical purposes, the main value added by these batteries is not really the size of their storage capacity (afterall, their capacity is tiny relative to the grid's needs), but their ability to quickly sink or supply massive amounts of power.
If these batteries had 10x the storage capacity, but 1/10th the power output, they'd miss out on their biggest advantage, which is capturing mid-day solar oversupply, and providing virtual grid inertia.
Long duration, lower-power batteries will have an important role to play once grids get further along in renewable adoption, but for now, short duration power-supply is the main value they add, and it makes perfect sense to quote battery numbers in terms of power. (not that I'd complain about providing capacity numbers too)
I mean, both is important. Pumped hydro can have quite large amounts of storage, but supply comparatively little W of power.
Makes sense. With battery technology improving and being the cheapest it's ever been, why not? This is probably the direction most countries will go in the future.
For comparison, US grid capacity is about 1250 GW, average usage 500 GW.
So, this adds over two minutes of average usage.
https://seia.org/research-resources/energy-storage-market-ou... says total storage now is about 200 GWh, or about 25 minutes of average demand.
So if ALL power generation of the US would stop right now, EVERYTHING would still have power for 25 minutes. (ignoring all safeties tripping, and perfect load balancing)
That sounds so impressive.
No. Because neither storage nor generation is evenly spread. In some places you would have nothing, in some you could have potentially hours.
In practical terms, you would most probably get nothing, because situation like this would lead to complete grid breakdown and interruption of service.
Technical detail question: if all of those batteries were on connecting allowing feeding back to the grid, would they be able to synchronise the frequency/phase? What's the threshold/requirement for that to happen?
It's not public.
Only if that battery was connected to 500GW of inverter capacity (and the grid was a spherical chicken -- enough intertia-replacement devices to keep timing working, enough capacity to link supply with demand etc)
inertia-replacement is what batteries do best, so in this kind scenario that's probably the least of the problems.
That means a huge ability to absorb production or consumption peaks!
Compared to what is this a good measure?
"How much is needed during no sun and no wind" could be reasonable comparison.
Am I correct to assume all these grid batteries are all made in China as well?
Grid batteries was one of the few areas that escaped Trumps gutting of the IRA and was included in other Infrastructure bills.
And a side effect of the EV market getting hobbled also redirected battery factory capacity from that market.
I'm not sure what's online yet but there is a pipeline.
edit an estimate from earlier this year:
> By the end of 2025, 20 gigawatt-hours of dedicated storage cell lines had opened, and the industry is on pace to hit 96 gigawatt-hours by the end of this year.
China, the electrostate
It's nice to see more storage being added, but we have keep thr order of magnitude in mind: the peak electricity demand for the US is 750GW, so the added storage for the past 3 month corresponds to just 96 seconds of peak consumption.
There's still a very long way to go !
As others have stated, neither storage nor generation is evenly spread.
But, like with UPS, 96 seconds is ample time to let delicate systems glide to a standstill or to start the diesel generator.
Obviously there are a variety of sizes and configurations, but if you assumed 3.5MWh per 20ft container, that's 5771 containers, and if you assumed a PCS container per two battery container, that's 8656 containers, just for an idea of the scale.
and then it's roughly just a rectangle of 100 by 100 containers, still big, but maybe not sooo big :-)
or a cube of 20x20x20 containers, seems small enough. (funny how we interpret numbers and sizes
I've always wondered why they don't stack them in deployment -- the containers are obviously fine with it! -- but I guess land is cheap enough not to bother.
Horizontally they need plenty of room for airflow, as each container has some HVAC-or-whatever module on the side. But vertically...
I always thought they were spread apart so much to further reduce the chance of catastrophic spread of fire from one container to another.
That would be a lot harder if you stack them since heat likes to rise.
But no clue if that is the actual reason.
Yeah, that's probably part of it. Some do have explosion vents in the top of the container.
It'd just be impressive to see a giant wall of battery. A bunch of little batteries camping in a field doesn't play the same visually. Ah well.
I would assume it has something to do with fire hazard ?
That's one third of what China added in December, 2025:
https://cleantechnica.com/2026/07/16/chinas-batteries-move-b...
Presumably this is only capacity connected to the grid, and doesn't include isolated data centre builds?
I was snobby and looked up the numbers because I didn't think this is relevant. But it is.
Space-Tesla installed 3 GWh in 2026 alone.
> I was snobby and looked up the numbers because I didn't think this is relevant. But it is.
Kudos to you for bein' "that guy". So many folks sit and comment while having the world's biggest library of information on just about every topic right there at their fingertips and still can't be bothered to take the 30 seconds to look up something they don't know about on their favorite search engine. I appreciate you for havin' done "the right thing" here. :)
https://seia.org/research-resources/energy-storage-market-ou...:
- The utility-scale market continued underpin growth, with 18 GWh installed, largely supported by seven gigawatt scale projects. Arizona installed over 6.2 GWh of utility scale projects, the largest quarterly deployment for any state in history.
- In the BTM space, residential storage added 657 MWh and commercial and industrial (C&I) added 1.8 GWh, largely on the back of demand from data centers.
⇒ it includes data centers
Batteries are great but every country still needs generation to charge them up. Some of the big gentailers build very little new generation capacity.
There's likely some spare solar capacity that will help. Currently the peak of solar is almost counterproductive, but converting that to storage is good for both the consumers and the power plants. (Less feed in during the day, lower evening peak)
How many batteries in parallel would you need to capture the power of a lightning strike?
As far as I know, we have yet to figure out how to capture power from a lightning strike. There is a lot of energy there, but it's static electricity which is completely different from what any grid runs on.
You'd probably use some kind of capacitor
To capture it? Quite a few I'd imagine. The energy you could collect though from one hit is quite low.
yea, i think the low efficiency (plus how to predict where lightning would hit!). Might as well just put up a wind turbine, since wind is much more predictable, not to mention easier to harvest.