Storage: Ugly in the Green Closet - by Doug Mohney

Views and Opinions on Green IT (Aug 12 2010)

1. 

   Green-a-holics may love wind and solar, but the breeze comes and goes while the sun goes down every night.   Being able to store power is the ugly part of best-loved green options and it's not easy.

   Beacon Power (www.beaconpower.com) is getting buzz this week because it landed a $43 million Department of Energy loan guarantee for a 20 megawatt flywheel plant in Stephentown, New York.  Yes, you read that correctly, flywheel : taking electrical energy and putting it into kinetic, then pulling it out again when needed.  The flywheel plant will be used to "absorb" energy from the local grid and pump it back in when needed.

   In essence, the flywheel plant -- with two more New York facilities in the pipeline -- will act as a big energy buffer.  The 20MW plant will provide about 10 percent of New York's total "frequency regulation" capacity on a typical day, avoiding the need to fire up a natural gas plant to cover peak needs.   One recent study asserts that 30 to 50MW of "fast-response" energy storage can provide the same or better results as a 100MW combustion turbine.

   While the Beacon flywheel is a carbon-fiber-based device spinning at 16,000 rpm and operating in a vacuum, it's still, well, Victorian as William Gibson might say.  I suppose it beats the heck out of pumping water up and down or compressing air for power storage, but there's something just a wee bit offensive about all those moving parts in an ICT world.

   Batteries?  Xcel Energy and others are running sodium sulfur batteries as storage devices for wind power; Xcel's battery  out in Minnesota next to an 11 MW wind farm is about the size of two semi trailers and can store about 7.2 megawatt-hours of electricity and can charge/discharge at one megawatt.  

   Further down the road, a fuel cell cycle based on Bloom Energy technology (or to be fair, someone else's) might work, with energy going into a Bloom Server to split water into hydrogen and oxygen, but Bloom says it won't have maturity for that sort of thing for about a decade -- and it is the big optimist in the room for fuel cells.

   Fortunately, there are a lot of different people working on the problem of storage. Unfortunately, we are just getting to the point to scaling up power storage and buffering solutions. 

   Bookmark or Share this article

Login to comment.

Related Articles