Concentrated photovoltaic (CPV) technology is one of the newest players on the solar energy scene. These systems are unique because sunlight is concentrated through a lens onto high performance solar cells, thus increasing the electricity generated. Panels are mounted on tracking systems to maximize the benefit of each ray of sunlight.
SolFocus, a solar startup based in California has designed a promising CPV panel for medium to utility-scale applications. Let’s explore some of the impressive characteristics of SolFocus’ 1100S:
Most Efficient PV Panel on the Market
Scientific journals are full of reports of recent advances in solar cell efficiency. Although this is very encouraging, it is hard to know how these breakthroughs will perform outside of the laboratories and when they will hit the market.
SolFocus says that it has the most efficient panel available on the market today. The panel efficiency of their 1100S system is 25%. Keep in mind that panel efficiency is different from cell efficiency. Panel efficiency considers the panel as a whole and is lower than cell efficiency.
Increased efficiency will decrease the cost of solar energy. Lower manufacturing costs, fewer raw materials, and less land will be needed to generate the same amount of energy.
Dual Land Use
According to SolFocus, one megawatt of panels requires 6 to 8 acres of land. CPV panels are mounted on tracking systems, allowing for the land underneath to be utilized as well. Shade crops can be cultivated under the solar panels, increasing the diversity of crops that can be cultivated in sunny regions.
Over 95% Recyclable
The solar industry has been criticized for creating a product that is difficult to recycle. Although the useful life of a solar panel is around 30 years, it is important to consider this while designing the product. SolFocus panels has achieved high rates because the two main materials used are glass and aluminum.
Energy Payback of 6+ Months
In the 1970’s, manufacturing a solar panel required as much energy as the panel would generate over its 20 year lifespan. That means that older solar panels didn’t result in any net energy gain.
“Solar power has been criticized in the past” for requiring too much energy to produce, said Vasilis M. Fthenakis of the Brookhaven National Laboratory in Upton, N.Y. “But what we find out is that those criticisms are not true with the new technologies.”
The four popular kinds of solar cells: multicrystalline silicon, monocrystalline silicon, ribbon silicon, and thin-film cadmium telluride have an energy payback between 1 and 3 years. Certainly solar technology has come a long way, but SolFocus is leading the industry with panels that boast an energy payback of just over 6 months.
Manufacturing Elements Similar to Auto Industry
With a wealth of knowledge in manufacturing products with glass and aluminum, some of the best qualified people for designing SolFocus’ manufacturing automation systems are from the auto industry. One of the keys to producing a cost-effective CPV panel is an automated manufacturing process.
“We have to design for manufacturability,” said Nancy Hartsoch, VP of Marketing for SolFocus. “Otherwise, we will end up with an expensive lab experiment.”
The challenge that many solar technologies are encountering is to take these products out of the laboratories and into the market. What will make or break the CPV industry is the ability to manufacture product at the scale needed while keeping costs low.
Silicon shortages have held the solar industry back in recent years and boosted panel prices. SolFocus’ 1100S however “uses approximately 1/1,000th of the active, expensive solar cell material compared to traditional photovoltaic panels.”
SolFocus has several installations planned in 2009 in Spain and Greece. It will be great to see how this technology performs in the field.
Photo Credit: SolFocus