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Power Grids: The Huge Battery Market You Never Knew Existed
ashshy writes Unlike the obvious battery needs for smartphones or electric cars, many consumers are unaware of the exploding need for enormous battery banks as modern power grids are bringing a whole new set of requirements. From the article: "'Our electricity grid was built a certain way, and that way is to have on-demand production,' Argonne National Laboratory battery researcher Jeff Chamberlain explained. 'So as I flip my light switch on at home, there's some little knob somewhere that turns the power up. There is no buffer. It's a very interesting production cycle compared to other consumer goods. It was built a certain way, and the grid is currently changing in two different ways. One is, first our demand is increasing. But another is, around the world human beings are trying to get off fossil fuels and that means using solar and wind. Well, we cannot turn up the sun or wind, or turn down the sun or wind according to our energy needs. So the more those technologies penetrate the grid, the more you need energy storage. You need a buffer. And that is a very difficult challenge that's similar to transportation because it's cost-driven,' Chamberlain said. 'But it's also different from transportation because we're not limited by volume or mass like we are in vehicles. We're working on energy storage systems that are stationary.'"
Pumped storage costs about $200 million per GWh of electricity stored to build. It needs specific geography, high and low reservoirs close to each other to reduce losses pumping water uphill over long distances. It also needs a guaranteed supply of water, lots of it and the sunny parts of the US where large amounts of solar power are being generated are distinctly lacking in water to the point of being either deserts or often in drought conditions during the summer. Pumped storage is also lossy, typically about 65% efficient round-trip.
Mass battery technology costs about ten times as much as pumped storage ($2 million per MWh for sodium/sulfur batteries from NGK), flywheels are a bit less but still a lot more than pumped storage. Cheaper methods of energy storage like compressed air tend to be very lossy.
Grid gas, coal and nuclear generators don't need storage as they either run flat out to meet the instantaneous demand and they can throttle back in quieter times. At the moment intermittent wind and solar generators use the grid as free storage but the more intermittent power that is added to the generating mix the more that storage will be needed to deal with peak inputs and debits. Getting wind and solar farm operators to pay for this extra storage probably isn't going to happen, sadly.