Solar cells have been around for 30 years, but have never made huge inroads into the energy market because they’ve always been more expensive than other ways of producing electricity. Now an MIT spinoff claims it’s going to make solar power cheaper than coal, not through any dramatic change in the technology but with a suite of more subtle improvements.
Electricity produced by today’s solar cells costs the consumer about 25 cents per kilowatt-hour, says Frank van Mierlo, president and CEO of 1366 Technologies, based in Lexington, MA. By contrast, van Mierlo says he pays about 19 cents per kilowatt-hour in Lexington, with the electrical grid fed by coal-powered and nuclear plants. By the year 2012, van Mierlo’s company hopes to bring the cost of solar power down to 10 cents per kilowatt-hour.
That proposition sounds valuable to local VCs. North Bridge Venture Partners and Polaris Venture Partners together led a Series A funding round for 1366 worth $12.4 million, the company announced today. MIT, which is licensing patents related to the solar cells to 1366, also has a “significant equity stake” in the company, van Mierlo says.
Carmichael Roberts of North Bridge says the climate is ripe for a renewable energy venture. “Obviously cleantech is a big deal, solar is a big deal,” he says. With the rising cost of oil, the difficulties inherent in depending on foreign energy sources, and growing concern about greenhouse gases, the market is ready for solar power if the costs can be competitive with coal, one of the cheapest energy sources, Roberts says. “Whole countries are betting on solar, so we feel pretty good about the demand.”
Van Mierlo says that 1366 is taking a “plain vanilla” approach to improving solar cells. The company will concentrate on cells made of multicrystalline silicon, which is already the lowest-cost type of solar cell. (More than half of today’s solar cells are of this type, with the majority of the rest based on monocrystalline silicon, which is more efficient but also more expensive—and so ultimately about the same cost per watt.) 1366 plans to boost the efficiency of multicrystalline-silicon-based cells using a series of design improvements developed by Emanuel Sachs, who specializes in the design of manufacturing processes at MIT’s Laboratory for Manufacturing and Productivity. Sachs, who cofounded 1366 with van Mierlo, has years of experience in photovoltaics, having founded Evergreen Solar of Marlborough, MA, in 1994, based on his invention of the “string ribbon,” a cheaper way of making solar cells. (He also invented a three-dimensional printing technology that was commercialized through another MIT spinoff, Z Corporation.)
One of Sachs’ innovations that 1366 will employ is a replacement for the flat copper wires currently used to connect several solar cells within a larger, glass-encased module. “All the light that hits those wires is reflected right back out of the module and lost,” Sachs says. His new wires have tiny mirrors embedded in them at just the right angle so that the reflected light hits the inner surface of the glass at an angle and is reflected again, this time back into the silicon, so more of it can be absorbed and converted to electricity. The wires alone, which don’t require any change in the manufacturing process for the modules, increase efficiency by about 3 percent.
But changes to the architecture of the solar cell itself bring about an even greater efficiency bump