Store wind energy for later? Idea still inefficient

Experts try to improve on two underground vaults that use compressed air

Wind power is unreliable. No one can turn up the wind every time electricity demand peaks. So some utilities are looking at ways to bottle up the wind’s energy and store it underground for later use.

“The wind blows a lot at 2 in the morning, so it makes sense to save it and use it at 5 in the afternoon when everyone comes home from work,” said Georgianne Peek of Sandia National Laboratories in New Mexico.

Compressed air energy storage (CAES) uses off-peak electricity from wind farms or other sources to pump air underground. The high pressure air acts like a huge battery that can be released on demand to turn a gas turbine and make electricity.

However, a good portion of the input energy is lost in this process, making CAES one of the least efficient storage technologies available.

MSNBC