Solar power has held out a promise of energy independence for a very long time. Unfortunately, its taken a very long time to become a significant part of the energy production in the US. California leads the way with solar power, thanks to rebates and tax initiatives.
I was fortunate enough to be able to take advantage of that in putting solar power on my own home and as Trustee for Chico Unified School District, I spearheaded their first ever solar power installation
at Little Chico Creek Elementary School which you can see online here
The panels used for both of those projects had solar to electricity conversion efficiencies of about 14-15%, which is normal for today’s silicon solar cells. So its with some real excitement that I found on the U.S. Department of Energy website news of a real breakthrough in solar energy efficiency
From the article: "…with DOE funding, a concentrator solar cell produced by Boeing-Spectrolab has recently achieved a world-record conversion efficiency of 40.7 percent, establishing a new milestone in sunlight-to-electricity performance." Ever since solar cells were invented to power satellites for the space program, improving conversion efficiency has been a slow process as you can see in the graph below.
Now here’s where it gets really interesting.
A page linked from Wikipedia’s article on solar energy calculates the land area that would need to be covered by solar collectors at 8% efficiency to meet the world’s energy needs (18 Terawatts using 2003 figures). At this new 40% efficiency, it looks like a square 265 square miles American southwest would be enough to supply the
entire world energy needs. Just supplying the USA would take about 25% of that land area. It’s possible. It’s within our reach.
The big question is: will it be cost effective to produce this new type of solar cell?
Right now, off the shelf silicon solar panels are still so expensive that rebate and incentive programs are needed to make it cost effective. Let’s hope that congress will take our presidents call for oil independence seriously enough to put some funding behind this new discovery.