The National Renewable Energy Laboratory (NREL), and their industry partner Solar Junction, have just set the bar even higher in the race for ultra-high-effiency photovoltaic (PV) cells by achieving another world record of 44% efficiency.
The newest cells build on previous successes with multi-junction PV cells (which use layered semiconductors, with each layer optimized to capture different wavelengths of light) and combine them with low-cost concentrating lenses to multiply the intensity of the sun's energy hitting the cells.
Last year, NREL and Solar Junction set a record in efficiency with their SJ3 cells, which are designed for use in utility-scale concentrated solar photovoltaic projects. The SJ3 was verified as being able to convert 43.5% (at 415 suns - a measurement of the intensity of the sun's energy when multiplied) of the energy in sunlight into electricity, but this latest iteration set a new high of 44% efficiency (at 947 suns).
The breakthrough garnered NREL yet another R&D 100 award from R&D Magazine, their third so far, and according to them, it, along with other advances, could "pave the way for a 50%-efficient solar cell in the not-distant future".
Advances such as these are great showcases for the possibilities of public/private partnerships, as Daniel Friedman, manager of the NREL III-V Multijunction Photovoltaics Group states:
"This is really a classic example of NREL developing something and then industry picking it up and running with it and making it a great commercial success. We started with some very basic materials research. We took it to the point where it made sense for industry to take over and take it to the marketplace.
We conceived the cell, demonstrated the individual parts, and let the world know about it. But Solar Junction put all the parts together with record-breaking results, made it work with MBE, and commercialized it at a time when no one else seemed to be interested in or able to do it." - Friedman
Read more about this advance in ultra-high-efficiency PV cells at NREL: Award-Winning PV Cell Pushes Efficiency Higher