Solar Energy for a Rainy Day

Nov 18, 2013

Credit Stock Image

The cost of solar panels has dropped so much in recent years that they’re becoming more common everywhere you look. But storing the energy for a rainy day has been a problem. 

Now another form of solar electricity promises to extend the reach of the sun’s energy and help make existing fossil fuel plants more sustainable.

It’s called “Concentrating Solar Power” or “C-S-P.”  Utility scale power plants use mirrors to reflect and focus sunlight.  The resulting heat spins a large turbine to make electricity, the same way conventional power plants do. But coal and natural gas can generate electricity on demand.  And thanks to CSP, so can the sun. The heat stored in solid or molten materials and used on demand the way fossil fuels are.

Ranga Pitchumani
Credit Virginia Tech

Ranga Pitchumani, is Chief Scientist and Director of the Concentrating Solar Power program for the U.S. Department of Energy   Initiative, and a Professor of Mechanical Engineering at Virginia Tech.   

“Concentrating solar power plays very nicely with conventional fossil generating sources.  By virtue of the fact that the turbine is the same for any thermal power generation plant you can actually integrate Concentrating Solar Power to add a boost to a fossil generation plant very easily and there are plants that exist of that kind.”

So far, most Concentrating Solar Power is generated in the southwest, but costs for all forms of solar energy have been dropping in recent years, making it more attractive in less sunny parts of the country.  And because utilities can add solar power to their existing power plants, the fear of job loss to heavy coal producing regions may be lessened, making the transition to green energy easier.

“The advantage is that the more solar you integrate into this plant the less fossil (fuel) you burn and therefore you reduce the carbon footprint.  And it uses existing infrastructure and it’s the same utility operators, the same plant operators so nothing goes away, it’s just adding on to existing infrastructure."

Pitchumani oversees a number of projects across the nation aimed at streamlining the adoption of solar power. Studies suggest concentrating solar power technology systems could provide approximately one-quarter of global electricity needs by 2050.