SolFocus Receives $25 Million in Funding
by Justin Thomas, Virginia on 08.15.06
SolFocus, which recently teamed up with Xerox PARC (details), has now received 25 million dollars in venture capital funding to manufacture it's innovative solar panels. SolFocus' panels are much more compact, and use much less silicon than regular panels because they use lenses and mirrors to concentrate sunlight. The concentrators magnify sunlight 500 times, which according to the company, is the "sweet spot" between higher energy production and excessive heat. A second-generation design squeezes the process into a single glass block (seen here). The blocks have two sets of mirrors: mirrors on bottom face reflect sunlight back to mirrors on the top face, and these in turn reflect the light on to one-millimeter-square photovoltaic cells popped into the center of the bottom mirrors.
Silicon-based solar panels today cost close to $3 per watt to produce, SolFocus will manufacture solar systems at $2 per watt when it opens its first concentrator plant next year. Larger scale production (in the area of gigawatts) will cut the cost per watt to just 50 cents. The second generation should cut costs further, says Conley, to as low as 32 cents per watt.
The products are aimed at the commercial market, such as retail stores or office parks. SolFocus also intends to build large-scale power generation, where a field of panels could generate several hundred megawatts of power, Conley said. The company intends to have a 100-megawatt manufacturing facility in India operating at the end of next year, he said. SolFocus then intends to replicate that plant in China, Europe and somewhere in the Americas.
:: SolFocus
It should be noted that only direct sunlight can be concentrated.
So this technology works well in areas with many sunhours such as California or Spain.
However, in areas with many cloudy days most light is diffuse (i.e. scattered by the clouds) and this technology is pretty useless.
It's not clear, perhaps it is to some, whether or not these panels track the sun as the Sirling Energy concentrators do. Do they have to track the sun?
I like the idea of trying to fit various solar technologies together. As an example, think about siting for both wind and solar and putting a Sirling Energy concentrating solar assembly on top of one of these vertical wind turbines from TMA http://www.tmawind.com/
What if TMA used the Chinese MagLev technology http://www.treehugger.com/files/2006/07/china_unveils_w.php with their 50-55% efficient verticle turbines?
Detailed article about the SolFocus technology appeared in MIT's tech review recently
http://www.technologyreview.com/read_article.aspx?id=17246&ch=biztech&sc=&pg=1
This is a good idea but a better one is to use large fresnel lens instead of tiny ones which ensure you use even less PV. The is the tech behind the SunCube rooftop concentrator:
http://www.greenandgoldenergy.com.au/
Another problem with SolFocus is that they use regular silicon based PV (SunCube uses triple junction cells that have more than double the efficiency) which means it'll lose efficiency rapidly as temperatures rise. Regular PV run at peak power at the optimal temperature of 25%. The higher the temperature, the less power will be produced.
To clarify the last sentence in my previous post, I was referring to ambient temperature.
Pieter, you don't use your car to drive across the ocean, so why are you trying to create a similar straw man argument here?
Solar panels are wonderful for arid climates where hydro and wind might not be plentiful. We don't get our energy from one source now, why act like we ever would?
i dont care if its made of marbles and toilet paper rolls, if they can gimmie 1$/w or less, this is a good step forward.
i agree that the larger units that Manu mentioned are better efficency, but they may not be as practical for the home user.
fyi, i say screw the green roof and gimmie solar.
froggy
@ben schiedelman
I think you misinterpreted me: I am all in favour of solar energy. I just meant to give some additional info about the application range of this product: If you live in an area with many sunshine hours this could be a good product, but if you live in an area with lots of cloudy days (like the Netherlands, were 60% of the light is diffuse) a 'normal' PV-panel will be more usefull.
To use your comparison: For most people it will not be so self-evident that this car is great for land, but not so good for the ocean.
What Manu says is pretty false.
- What reduces PV crystal size is concentration factor, which can be independent on lens size (you only need to scale the whole system!)
- Solfocus does not base on silicon, but in highly efficient multijunction cells from Spectrolab