PVT Solar Bags Cash to Peddle Electric-Heat Combo

PVT Solar, which is developing a way to capture and use the heat from a solar-panel rooftop system for heating water and homes, has raised a series B round of $13.7 million and also brought in a new CEO, Vikas Desai, the company plans to announce Tuesday.

PVT, which is based in Berkeley, Calif., but plans to move to nearby Fremont soon, received some high-profile coverage of its plan in 2008. But back then, the company was still mum about its technology, presumably because it was still fine-tuning it.

One of PVT”s investors has called the technology “game changing.” While PVT may be taking a different approach to harnessing the heat, the concept is hardly novel. A solar electric system is comprised of panels that can mostly only convert 10-20 percent of the sunlight that hits them into electricity, depending on the types of materials used.

The process also generates heat, which can threaten the performance of the solar cells inside the panels. In fact, the waste heat has been a major concern for roofing material companies that are looking at building solar cells into their products.

What PVT has developed is a system to capture the heat and funnel it into the home to heat water and provide heating and cooling of the interior space (see video demo). The company might add heat-collecting plates along with the solar panels to generate more heat. To move the heat inside the house, exhaust/intake vents will have to be drilled on the roofs. The heat and the outside air are sucked into the vents and through what it calls an energy transfer module, which is made up of a filter, heat exchanger and fan. The module turns the hot air into useful heating and cooling medium.

PVT is selling the entire system of solar panels and heat harvester, but it doesn’t make its own solar panels, it buys them from suppliers. The company has designed its own mounting system that eliminates the gap between solar panels to better collect the heat.

Many other companies are engineering hybrid systems that can make electricity and harvest any resulting heat for heating and cooling. Some of these designs come with reflectors to concentrate the sunlight onto solar cells and additional equipment to harness the heat. Companies in this electricity-heat generating field include Chromasun, BrightPhase Energy and Cool Energy.

PVT said it now counts Meritage Homes, Joseph Carl Homes among its customers, but it didn’t provide details of its sales. The company’s B round came from Sigma Partners, Japan-based Energy & Environment Investment and Khosla Ventures. The company raised $5 million for the A round.

In addition to Desai, who was vice president and general manager of SunPower’s residential and light commercial business, PVT also is adding five other new executives: Steve Walden as its new director of national sales; Mike Harshfield as the director of field operations; Ian Smith as director of product development; Ram Narayanamurthy as the chief science officer and Wade Albritton as the director of mechanical systems.

For more research on cleantech financing check out GigaOM Pro (subscription required):