Solution to high energy costs could lie underground
Sandia National Laboratories researcher Georgianne Peek thinks a possible solution to high energy costs lies underground – and it’s not coal or oil: It’s compressed air energy storage.
“Until recently energy has been relatively inexpensive. But now prices are rising dramatically, and we need solutions,” Peek said. “CAES and other storage technologies are not the only answer to our energy needs, but they can be an important part of the solution.”
CAES facilities function like big batteries. Electric motors drive compressors that compress air into an underground geologic formation during off-peak electric use times like evenings and weekends. Then, when electricity is needed most during high-demand times, the pre-compressed air is used in modified combustion turbines to generate electricity. Natural gas or other fossil fuels are still required to run the turbines, but the process is more efficient. This method uses up to 50 per cent less natural gas than standard electricity production.
While the concept of compressed air energy storage is more than 30 years old, only two such plants exist – a 17-year-old facility in Alabama, and a 30-year-old plant in Germany, both in caverns in salt domes. A third is being developed near Des Moines, Iowa, in an aquifer. In addition, the Public Service Company of New Mexico and several other US utilities are considering CAES to help mitigate potential problems associated with the high penetrations of wind generation in their systems.