MIT spinoff shoots for solar power at $1 per watt

An MIT spinoff with Ethernet co-inventor Bob Metcalfe on its board has landed seed money to bring the cost of solar power to the much-pursued level of $1 per watt.

Called 1366 Technologies, the company raised $12.4 million from North Bridge Venture Partners and Polaris Venture Partners, where Metcalfe is partner, to build a pilot solar cell plant in Lexington, Mass., co-founder Ely Sachs said on Wednesday.

1366 Technologies co-founder and MIT professor Ely Sachs.

(Credit: 1366 Technologies)

Rather than design new materials in pursuit of a solar cell efficiency breakthrough as many newly formed solar companies are doing, 1366 Technologies is focusing on manufacturing improvements around silicon cells.

A combination of two manufacturing technologies will allow it to make polycrystalline cells 25 percent more efficient at converting light to electricity, executives said.

The technology was developed in the labs of Sachs, a noted professor at Massachusetts Institute of Technology who developed the "string ribbon" manufacturing process commercialized by Evergreen Solar.

Its goal is to produce solar cells at one dollar per watt, or 10 cents per kilowatt-hour by 2012, which is about half the manufacturing cost now. At that price, solar power is competitive with electricity from coal.

The company chose to focus on silicon because it's a material that's well understood, nontoxic, and reliable. Polycrystalline silicon is the most commonly used solar cell material.

"(Silicon) has all the fundamentals in place," said Sachs. "It has been on a 20 percent learning curve, meaning that over the 30-year history of photovoltaics, costs have declined by 20 percent every time the cumulative production levels double."

One technology the company is commercializing is called "grooved ribbon," an alternative method for wiring solar cells together. Small mirrors reflect light back onto solar cells that would otherwise be reflected away from the cell. That technique adds about a 3 percent improvement in cell production.

The second technology the company is working on is a way to take low-cost silicon wafers and package them for cell production, Sachs explained.

Both processes, which the company has sought patents for, can be used in existing solar manufacturing sites.

In fact, in addition to planning to make its own 25-megawatt pilot plant, 1366 Technologies is also in discussions with other solar manufacturers to license its technology, said company President Frank van Mierlo.

The company's name comes from the solar constant, or the average amount of solar radiation that hits Earth's atmosphere, which is 1366 watts per square meter.