How to Double the Power of Solar Panels
How to Double the Power of Solar Panels - Technology Review
In an attempt to further drop the cost of solar power, Bandgap Engineering, a startup in Woburn, Massachusetts, is developing a nanowire-based solar cell that could eventually generate twice as much power as conventional solar cells.
That’s a long-term project, but meanwhile the company is about to start selling a simpler version of the technology, using silicon nanowires that can improve the performance and lower the cost of conventional silicon solar cells. Bandgap says its nanowires, which can be built using existing manufacturing tools, boost the power output of solar cells by increasing the amount of light the cells can absorb.
Right now most solar-panel manufacturers aren’t building new factories because the market for their product is glutted. But if market conditions improve and manufacturers do start building, they’ll be able to introduce larger changes to production lines. In that case the Bandgap technology could make it possible to change solar cells more significantly. For example, by increasing light absorption, it could allow manufacturers to use far thinner wafers of silicon, reducing the largest part of a solar cell’s cost. It could also enable manufacturers to use copper wires instead of more expensive silver wires to collect charge from the solar panels.
These changes could lead to solar panels that convert over 20 percent of the energy in sunlight into electricity (compared with about 15 percent for most solar cells now) yet cost only $1 per watt to produce and install, says Richard Chleboski, Bandgap’s CEO. (Solar installations cost a few dollars per watt now, depending on their size and type.) Over the operating lifetime of the system, costs would come to between 6 and 10 cents per kilowatt-hour. That’s still higher than the current cost of natural-gas power in the United States, which is about 4 cents per kilowatt-hour. But it’s low enough to secure solar power a substantial market in many parts of the world where energy costs can be higher, or in certain niche markets in the United States.