Power pack: Each Semprius solar panel is made of an array of 660 lenses that focus light on 660 tiny solar cells.
Concentrated solar panels use tracking systems to follow the sun. These are expensive and can be unreliable, and they can’t be mounted on most roofs, limiting their application. They also only work in very sunny areas, since overcast skies can cause their power output to drop far more than with a conventional solar cell.
But as the cost of tracking systems comes down, and the efficiency of multilayer solar cells increases, concentrated photovoltaics are beginning to look more attractive. Large installations of this type of solar module have been increasing in recent months.
Semprius is building its factory at a particularly difficult time for the solar industry. An oversupply and a reduction in manufacturing costs has led to a rapid drop in prices for solar panels, making it difficult for new companies to enter the market, and forcing some existing manufacturers out of business.
In response to falling prices, many solar companies, including Semprius, are focusing on improved efficiency. As long as manufacturing can keep costs down, increased efficiency lowers the cost per watt of solar panels. More importantly, it also lowers the cost of installation and related equipment, which can account for over half of the cost of solar power. Semprius is also leaning as much as possible on proven manufacturing technology, which could make it easier to scale up production and lower development costs.
Semprius has another advantage: a partnership with Siemens. In addition to providing direct financing (Siemens has a 16 percent stake in the company), Siemens provides experience in manufacturing and in building complete solar farms, and the partnership makes it easier to secure financing from banks.
The small factory that Semprius plans to open this summer will have the capacity to produce 30 megawatts of solar panels a year. Semprius expects panels produced there to be cost-competitive for some applications, Carr says. Increasing production to 100 megawatts would bring down costs enough for the technology to compete with cheap solar panels made in China.
Ultimately, the cost per kilowatt-hour for solar power depends on a number of factors, such as financing costs, the cost of land, local labor rates, proximity to transmission lines, and so on. But Carr thinks Semprius can generate solar power for less than 10 cents per kilowatt-hour, low enough to get a share of the utility market in many areas. What’s more, he says it can do this without the help of government subsidies.