Published on January 26th, 2013 | by Tina Casey9
Race To Break Solar Cell Efficiency Record Heats Up With New $12 Million Grant
The U.S. Department of Energy has just added another $12 million to an existing $35.8 million grant program aimed at producing the next generation of record-breaking solar cells that get closer to the theoretical maximum efficiency of about 30 percent. That goalpost was established back in 1961 and solar researchers have been chasing it ever since, but according to DOE a “sizable gap” still separates the current state of the technology from its best potential.
The grant program, called Foundational Program to Advance Cell Efficiency II (FPACEII) will cover a range of technologies including silicon-based and thin film solar cells.
The Limits of Solar Cell Efficiency
If you’re new to this topic and googling around, you’re going to see all kinds of numbers being tossed about, so it’s helpful to keep in mind that the FPACE grant program is focused on improving the ability of single-junction solar cells to convert sunlight into electricity.
Loosely speaking, single-junction refers to a solar cell made from one layer of material, typically silicon. Multi-junction cells are made with layers of different materials. They can achieve conversion efficiencies up in the 80 percent range but generally involve greater costs.
The Energy Department’s figure of “about 30 percent” for maximum conversion efficiency refers to silicon solar cells. Overall, the researchers who developed the theory (William Shockley and Hans Queisser) describe a best-case scenario of 33.7 percent.
Solar Cell Efficiency and the SunShot Initiative
FPACE II is part of President Obama’s SunShot initiative, which launched in 2011 with the aim of funding critical research to bring the cost of solar power down to parity with fossil fuels.
Aside from improving the efficiency of solar cells, SunShot is also designed to keep the U.S. in the vanguard of the international race to bring down the “soft costs” of solar power.
Soft costs include permits, inspections, installation and grid connections, which can account for about half the final cost of a typical installation. SunShot’s efforts in this area include developing models for affordable rooftop solar installations that can be replicated by the thousands.
We Are Building this Record Breaking Solar Cell Efficiency!
The first round of the program, FPACEI, kicked off in 2011 with $35.8 million in grants for 18 separate solar cell research projects, partnering the Energy Department with the National Science Foundation.
The goal was to push new technologies out of the lab and into the factory by developing more efficient solar cell designs, using cheaper materials and integrating mass production efficiencies into the research process.
For example, one grant went to a Texas-based company called Astro Watt, which is working on an ultra-thin, large-area crystalline silicon cell that could be produced in modules for 50 cents per Watt or in cells alone for 30 cents per Watt.
Another piece of the pie went to Colorado State University, for a project to improve the efficiency of current cadmium telluride solar cell technology without causing manufacturing costs to go up.
The biggest single chunk ($6,240,942) went to the National Renewable Energy Laboratory (NREL) and industry partners for a low cost thin-film solar cell project based on copper indium gallium diselenide, aka CIGS.
If CIGS rings a bell, you may be thinking of a new conversion record for CIGS set by a Swiss research team, which was just announced last week at 20.4 percent.
NREL’s goal for its project is only 16 percent, which sounds excessively modest except when you consider the integrated position of manufacturing in the FPACE program. The Swiss achieved their mark in the laboratory, which is all well and good but NREL’s goal applies to the final result when the cells roll off a commercial assembly line.
Another two projects worth highlighting involve developing low cost, laser-based manufacturing methods for silicon solar cells, with a total of almost $8 million split between Oregon-based Solar World Industries America (the largest solar company in the U.S.) and a team spearheaded by the University of Delaware
As for PFACEII, this round of funding is more specifically focused on developing model single-junction systems that “have the potential to approach Shockley-Queisser power conversion efficiency limits.”
If the grants bear fruit, when integrated with the manufacturing improvements under PFACEI, that will be a killer combination.
Stay tuned: the application deadline for PFACEII is April 28.
Update: the article has been corrected to name Colorado State University as one of the grant recipients. Thanks to Russell Geisthardt for bringing that to our attention.
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