Using a wind energy and expensive lithium-ion batteries, AES Energy Storage is making money by stabilizing the grid.
April 12, 2013
The conventional wisdom is that batteries, particularly lithium-ion batteries, are way too expensive to be used on the electricity grid in a financially viable way. Chris Shelton begs to differ and he has two years of data to make his case.
Shelton is the president of AES Energy Storage, which has developed 150 megawatts worth of energy storage projects in four locations using giant lithium-ion batteries. The trick to making them economic is using them for what they’re good at and in this case, that’s speed.
The company earlier this week said it has provided 400,000 megawatt-hours worth of frequency regulation services to the electricity grid in the mid-Atlantic states, a portion run by grid operator PJM. The battery–actually 16 connected batteries packaged in shipping containers–draws its energy from 61 mountaintop wind turbines in West Virginia with a capacity of 98 MW. That configuration consistently outperforms natural gas and coal power plants in providing the service, says Shelton. “It’s competing every day in getting selected and winning. It’s a commercial, scalable proof point that storage is economic,” he says.
Frequency regulation is one of those essential but invisible grid services that few people outside the utility industry are aware of. Electric current needs to be sent at a consistent frequency and when the amount of power that’s being pumped into the grid is out of sync with the amount of power that’s being consumed–essentially a supply demand imbalance–then service can be interrupted. Right now, fossil fuel power plants provide bursts of power into the grid to maintain that stability. Energy storage can perform the same task either by quickly absorbing or delivering power...