Solar Junction broke a world record for solar cell efficiency last week. The California company, which specializes in producing high-efficiency solar materials, announced that it has 5.5 mm by 5.5 mm solar cell with an efficiency of 43.5 percent.
“We achieved that using lattice-matching,” said Solar Junction spokeswoman Diandra Weldon. “Lattice-matching results in fewer defects and higher efficiency.”
Lattice-matched solar cells, according to scholarly articles, tighten the connections within solar crystals and allows them to cover more of the light spectrum. High-efficiency lattice-matched solar cells typically use different materials than regular commercial solar cells, which are generally constructed with silicon. High-efficiency silicon solar cells tend to achieve efficiency percentages in the low 20s.
One of the most common ingredients in high-efficiency multi-junction cells like the one Solar Junction announced is Germanium, a rare Earth mineral.
Solar Junction did not discuss in its release what materials it used to achieve its record-breaking efficiency, only that it reached that efficiency by incorporating Solar Junction’s proprietary adjustable spectrum lattice-matched technology, which it has branded A-SLAM.
The company’s technology was a success and broke the record by 1.2 percent, according to a press release. That’s significantly higher than the average efficiency gain achieved by previous record holders and demonstrates the company’s tremendous gains over a short time.
The 43.5 percent efficiency rating is at a strength of 400 suns and stays as high as 43 percent up to 1,000 suns, according to the release. Those efficiency ratings were especially remarkable when the cells were only measuring 41.4 efficient in the National Renewable Energy Laboratory tests two months earlier, according to the release.
Solar Junction builds cells primarily for the concentrated photovoltaics industry.
“What we’re really hoping for is that this technology will really help CPV to move forward,” Weldon said.
The announcement this week also highlight’s Solar Junctions vitality. The company has been competing with itself and breaking its own records, pushing for greater results, Weldon said.
“There’s no question that we’ve been on a nine-month tear,” Jim Weldon, CEO of Solar Junction, was quoted in the release. “We’ve delivered on milestone after milestone and attribute this to our superior performing technology platform, driven by our dedicated, hard-charging technical team, supported by our integrated in-house manufacturing line that has enabled, and will continue to enable, multiple iterations of product improvement on an accelerated timeline.”
Image courtesy of PV-Tech.org.