We’re all familiar with standard photovoltaic solar panels, and many of us are starting to become acquainted with solar thermal tech that uses the sun’s heat to generate power, but there’s also a third option. Over a dozen startups are working on ways to use mirrors and lenses to concentrate sunlight hundreds of times onto tiny, highly efficient solar cells. Called concentrating photovoltaic technology (CPV) the systems are meant to cut back on one of the most expensive parts of traditional PV: the silicon-based solar panel.
CPV startups say the latest tech can provide solar systems at a lower cost per watt by producing as much or more power from the same amount of silicon. Though many companies are just starting to bring products to market, and the systems seem to require a lot of moving parts, these 13 companies are working out the details:
SolFocus: The Mountain View, Calif.-based company is only a little over two years old, but has been amassing significant funds from well-known Valley firms to deploy its CPV systems. The startup already raised $95 million from New Enterprise Associates, Moser Baer India, David Gelbaum, Metasystem Group, NGEN Partners and Yellowstone Capital, and it’s reported to be looking to add between $60 million and $80 million in a Series C round.
The company also has a serious presence in Spain. Its sister company SolFocus Europe has offices in Madrid, Spain, and this week the company said it had completed the first 200 kW installation of a 3 MW concentrating solar PV plant owned by Spain’s Institute of Concentration Photovoltaic Systems (ISFOC).
Cyrium Technologies: Cyrium makes the multi-junction solar cells for concentrating PV systems — these cells have to be highly efficient and robust. Just this week the company says it has closed a Series B round of $15 million in funding led by David Gelbaum’s Quercus Trust, and including BDC Venture Capital, Chrysalix Energy Venture Capital, and Pangaea Ventures.
Solar Systems Tech: Founded in 1991 by John Lasich, Hawthorne, Victoria, Australia-based Solar Systems has developed the “CS500 dish concentrator PV unit,” which stands 14 meters high, has 112 curved mirrors (each 1.2 square meters) and tracks the sun on a mounted steel frame. The company only sells solar power plants with a minimum of 8 dishes, and it says the CS500 produces up to 30 percent more electricity per installed watt and is cheaper per installed watt than traditional PV.
GreenVolts: GreenVolts is a three-year-old, San Francisco-based solar startup that sells a sun-tracking concentrating PV system called the CarouSol that can concentrate sunlight up to 625 times. GreenVolts says the system can produce energy at less than half the cost of traditional PV.
In 2006 the company won the California Clean Tech Open business competition, and a year later raised a $10 million Series A round led by Greenlight Energy Resources and included Avista and other investors. The company said earlier this month it was looking to raise funding of “less than $100 million” later this year.
Concentrix Solar: The Freiburg, Germany-based company was spun out of the Fraunhofer Institute for Solar Energy Systems in 2005. The company sells concentrating PV plants called Flatcon, which the company says produce electricity 10 to 20 percent cheaper than standard PV.
For about two years the company has been operating a pilot production line and by the end of the summer plans to have started up another 25 MW production line. Concentrix is backed by Good Energies and Abengoa Solar and has a joint venture with Abengoa, called Concentrix Iberia, for the Spanish markets.
Silicon Valley Solar: The two year old company was founded by Patrick Callinan and backed by a $10.2 million Series A round from Bessemer Venture Partners. The company’s Sol-X concentrator is a flat plate internal concentrator, which is low cost and delivers two times the concentration and reduces silicon by 50 percent. The system also doesn’t rely on a tracking system, so there are fewer moving parts (which cuts the cost and complexity of the system).
Energy Innovations: “EI” is a startup that makes a variety of solar photovoltaic products, including the Sunflower, which the company claims is “the world’s first high-concentration PV system for both commercial rooftop and ground-mounted applications.” Energy Innovations is backed by Bill Gross (dotcom entrepreneur turned cleantech investor) and his Idealab incubator, as well as Mohr Davidow.
Soliant Energy: Soliant’s rooftop concentrating solar panels are the same dimension and weight as conventional PV panels, so are much easier to install than many of the other CPV systems out there. The systems use triple junction cells that can deliver 40 percent efficiency, and the lenses concentrate the sunlight by 500 times.
Amonix: Torrance, Calif.-based Amonix is almost 2 decades old, which has given them a chance to go through 6 generations of improvements on their high concentration PV systems. The lenses concentrate the sunlight over 500 times and the company says it manufactures its high efficiency solar cells “at existing microelectronic chip manufacturing foundries,” which can deliver significant cost savings.
Green & Gold Energy: This Australian startup was formed in 2005 with $250K in seed funding from the founder. The company has now grown large enough that it says it has already committed to sell 400 MW per year of its SunCube concentrating solar PV systems. The company only officially launched its SunCube technology in February of this year but says it intends to sell 1 GW of SunCube manufacturing facilities around the world. G&GE also claims it has “placed the largest CPV industry order to date for 105 MWs of Emcore’s world leading 1,000 sun concentrator cells.”
Pyron solar: We first heard about Pyron Solar when the company raised Series A financing from New Energies Invest for its concentrating solar PV systems. The company, which is headquartered in San Diego, Calif., has a working 6.6 kW prototype of its unusual solar system that floats in water, which helps to cool the system and can prevent damage. The solar setup uses three 15-meter-diameter arrays on a two-axis tracker with multi-junction PV cells from Spectrolab.
Sol3g: Like SolFocus solar concentrating PV system maker Sol3g is building out a part of the 3 MW solar system that belongs to the Institute of Concentration Photovoltaic Systems in Castilla La Mancha. Founded in 2004, the company is based in Cerdanyola, Spain, and says the PV surface of its system is 400 times smaller than that of a traditional PV system, “with the consequent cost saving.”
Cool Earth Solar: You might have seen pictures of this one across the web; the solar system that looks like a oversized foil balloon. Cool Earth Solar makes inflated mirror concentrators, half made of reflective mylar and half clear film. Inside the bubble is a high-efficiency PV receiver. The system is supposedly designed to be lightweight and easy enough to string up but rugged enough to withstand 100 mph winds. In February the company said it had raised $21 million.