Spectrolab is taking its high-flying solar cells and bringing them down to earth.

After building a reputation as the supplier of advanced cells for satellites, the International Space Station and two Mars rovers, the Boeing Co. subsidiary is gearing up for a major push into land-based solar installations.

The Sylmar company now has a very different challenge: competing with both traditional fossil fuels and a glut of low-cost silicon solar cells, especially those made by the Chinese, which have flooded the U.S. market in recent years.

"The cost of delivering solar has to be competitive," said Spectrolab President Troy Dawson.

But the company has an advantage matched by few competitors--ultra high-efficiency solar cells.

In 2009, the U.S. Department of Energy National Renewable Energy Laboratory verified that the thumbnail-size cells produced by the company reached a world record of converting 41 percent of collected sunlight into electricity.

And the commercial cells it markets for space applications have an industry-leading efficiency of more than 30 percent. By contrast, typical cells used in commercial buildings have efficiencies of 15 percent to 20 percent.

Spectrolab achieves it results by building what are called concentrated photovoltaic cells, which require sunlight directed by mirrors and lenses. As a result, the cells are installed in utility-scale arrays. Spectrolab does not provide the panels, mirrors or other optics needed for these arrays.

However, the total cost for such a system...