GreenVolts hasn't been too outspoken about their design until now,
except perhaps at trade shows. They've decided to take the cover
off for this announcement.
San Francisco solar startup GreenVolts today announced an agreement to build a demonstration solar power plant for Pacific Northwest utility Avista. GreenVolts was one of the companies featured in Green Wombat's Big Solar story that appeared in the June issue of Business 2.0. Avista (AVA), based in Spokane, Washington, will also make a "strategic investment" in GreenVolts. The terms of the deal were not disclosed. GreenVolts has developed a high concentration photovoltaic technology that features microdishes that track the sun and focus its rays on small but highly efficient solar cells. Rotating platforms hold 176 of the dishes. GreenVolts 1-to-20-megawatt power plants are designed to be placed near cities or utility substations to provide electricity during peak demand without the need for new transmissions lines or other infrastructure that often must be built for large-scale solar power plants located in the desert. In other words, GreenVolts offers a plug-in power plant designed to save utilities from having to crank up fossil-fueled power stations to provide electricity when demand soars in the afternoon.
...
Of course, GreenVolts will only score contracts with utilities if its plug-in power plants can produce electricity at competitive - or near competitive - rates. The key to doing that is the company's technology, according to Cart. He disappears and returns carrying a prototype of the GreenVolts microdish. It's about the size of an overhead projector - remember those? - and features a curved mirror that faces a module holding a tiny solar cell about the size a cameraphone lens. GreenVolts licensed the mirror technology from Lawrence Livermore Laboratories. "It gives us a mirror that is low-cost to produce, is highly reflective and highly durable," says Cart. The design allows the sun to be intensely concentrated on the solar cell, which is made by Boeing's (BA) Spectrolab subsidiary and is the world's most efficient at converting photons into electrons. The dish contains an automated pressure washing system, which keeps mirror clean and thus its efficiency high while reducing maintenance costs. The off-axis design prevents shade from falling on the dish when the sun is directly overhead.
Cart tapped the expertise of a cadre of engineers to help design the GreenVolts system, paying them in stock. GreenVolts' manufacturing VP is the CEO of Spokane fabrication company Ecolite, which is performing the mechanical design and assembly of the dishes and platform, which GreenVolts calls a CarouSol.
http://blogs.business2.com/greenwombat/2007/06/big_solar_green.html