Better solar for big buildings

A startup is selling cylindrical solar cells that can generate more power than conventional panels.

By Consulting Specifying Engineer Staff October 13, 2008

Solyndra , a startup based in Fremont, Calif., has developed a novel type of solar panel that’s cheaper to install and produces more power than conventional panels. The report appeared in MIT’s Technology Review .

Unlike conventional solar panels, which are made of flat solar cells, the new panels comprise rows of cylindrical solar cells made of a thin film of semiconductor material. The material is made of copper, indium, gallium, and selenium.

To make the cells, the company deposits the semiconductor material on a glass tube. That’s then encapsulated within another glass tube with electrical connections that resemble those on fluorescent light bulbs. The new shape allows the system to absorb more light over the course of a day than conventional solar panels do, and therefore generate more power. What’s more, arrays of these tubes offer less wind resistance than conventional flat solar panels, which makes them easier and cheaper to mount on roofs, the company said.

Solyndra is one of several companies that have recently received hundreds of millions of dollars to develop thin-film solar cells. Miguel Contreras, a senior scientist at the National Renewable Energy Laboratory , in Golden, Colo., which developed the semiconductor deposition method used by Solyndra, notes that several other companies have developed solar cells based on thin films using the same combination of semiconductors; these thin films are making possible a range of new forms for solar cells, including flexible solar cells and solar roofing materials.