Last Updated May 27, 2011 3:06 PM EDT
The Achilles heel of solar and wind power is its variability. Meaning, when the wind stops blowing and the sun sets, renewable power sources drop off and that can create headaches for grid operators trying to maintain a steady electricity supply. Now General Electric (GE) has a plan to fix it -- one inspired by its jet engines, no less.
GE has designed a natural gas-fired combined-cycle power plant that can start up or slow down rapidly -- like its jet engines -- to accommodate the fluctuations of renewable power. The design accomplishes four goals:
- It smooths out the electricity supply
- Allows for more renewable energy to be integrated into the power grid
- Saves wasted energy
- Greater efficiency typically means saving money as well
A quick comparison
GE's new FlexEfficiency natural gas power plant can ramp up energy production at a rate of more than 50 megawatts a minute. That's twice the rate of current industry benchmarks. And its fuel efficiency is greater than 61 percent. Some of GE's other power plants offer up to 60-percent efficiency, but they weren't able quickly ramp up energy production. It's that speedy ramp up capability, plus the efficiency that makes this particular design stand out.
Meanwhile, traditional plants like nuclear and coal-fired ones that provide base load power -- a set, minimum amount available to customers -- are designed to run continuously. These offer cheap energy, but they don't have the flexibility to power up or down quickly to meet demand. They can take hours, or even days to start up. This new GE design can start up in less than 30 minutes without wasting energy.
Why Europe and China go first
Unfortunately, the power plant will head off to Europe and most of Asia first. The plant was designed to operate at 50 Hz, the power frequency most used in countries around the world, including Europe and most of Asia. The U.S. would need a 60 Hz version, which GE does plan to build.
Listening to GE's webcast presentation, it's clear why the company went with the 50 Hz version first. Regions that have widely adopted renewable energy (like Europe), or are spending boatloads of cash in clean energy including wind power (like China) or that have disproportionately large demands for power (like Asia) go to the head of the line.
Photo from GE