Wiley said that a 300MW “pilot” project for Minnesota-based Great River Energy will be commissioned in 2023.
That project, announced in May last year, was originally due to be a 1MW/150MWh demonstration plant capable of outputting 1MW for 150 hours straight.
If the energy had gone up 300x from the originally announced pilot project the same way the power did, this would be a huge storage project boasting 45,000 MWh of storage capacity. It would surpass big pumped storage projects like the Bath County station (capacity: 24,000 MWh):
But this news article doesn't highlight any superlatives like that.
Reading between the lines, here's what I think has changed:
- The original announcement of a 1MW/150MWh project was an implicit admission that their battery could not charge or discharge quickly. It took nearly a week to fully charge/discharge. At the time they put a positive spin on it by emphasizing "long duration." That's not really an advantage, though. You can just discharge a high-rate-capable battery slower for long duration applications.
- Since this updated pilot project announcement touts more power and leaves any energy increase unspecified, I think that they found a way to increase the charge/discharge rate for their chemistry. That would be good because it would mean that the chemistry is suited for grid tied storage in general, more like lithium ion. If it can charge and discharge at high C-rates and it has lower lifetime cycle cost per megawatt hour than lithium ion batteries, it could be very successful.
EDIT: new user "tiddelypom" below says that he works at Form Energy and that this article is incorrect about the project size:
Not sure where that article got the 300MW number, the GRE project is on track for the original size.
If that is the case, my remarks about the limitations of batteries with low C-rates still apply. But my speculation that the company has drastically improved the C-rate of its chemistry would be incorrect.
> It took nearly a week to fully charge/discharge. At the time they put a positive spin on it by emphasizing "long duration." That's not really an advantage, though. You can just discharge a high-rate-capable battery slower for long duration applications.
If the price is right, long duration is just fine. One week of storage to get through a spell of cloudy weather or poor wind conditions is quite useful. It doesn’t obviate the need for daily storage.
To address slow charging, could you have an array of them, some charging and some discharging? But you would need maybe 7x more then, so they would need to be 7x cheaper to compete. (Not quite sure how the math works out to account for charge rates and weather.)
Charge rate is independent of capacity. A 3 C battery charges in 20 minutes, whether it's 1 kWh or 7 kWh. If you have 7 batteries, each charges in 20 minutes.
That project, announced in May last year, was originally due to be a 1MW/150MWh demonstration plant capable of outputting 1MW for 150 hours straight.
If the energy had gone up 300x from the originally announced pilot project the same way the power did, this would be a huge storage project boasting 45,000 MWh of storage capacity. It would surpass big pumped storage projects like the Bath County station (capacity: 24,000 MWh):
https://en.wikipedia.org/wiki/Bath_County_Pumped_Storage_Sta...
But this news article doesn't highlight any superlatives like that.
Reading between the lines, here's what I think has changed:
- The original announcement of a 1MW/150MWh project was an implicit admission that their battery could not charge or discharge quickly. It took nearly a week to fully charge/discharge. At the time they put a positive spin on it by emphasizing "long duration." That's not really an advantage, though. You can just discharge a high-rate-capable battery slower for long duration applications.
- Since this updated pilot project announcement touts more power and leaves any energy increase unspecified, I think that they found a way to increase the charge/discharge rate for their chemistry. That would be good because it would mean that the chemistry is suited for grid tied storage in general, more like lithium ion. If it can charge and discharge at high C-rates and it has lower lifetime cycle cost per megawatt hour than lithium ion batteries, it could be very successful.
EDIT: new user "tiddelypom" below says that he works at Form Energy and that this article is incorrect about the project size:
Not sure where that article got the 300MW number, the GRE project is on track for the original size.
If that is the case, my remarks about the limitations of batteries with low C-rates still apply. But my speculation that the company has drastically improved the C-rate of its chemistry would be incorrect.