Chinese solar panel manufacturer LONGi announced it has reached an efficiency of 26.81% for its HJT silicon solar cells on full-size silicon wafers through mass production. The record was confirmed by the Institute for Solar Energy Research in Hamelin (ISFH).
“Improving the efficiency and reducing the LCOE (levelized cost of energy) is the eternal theme of the development of photovoltaic industry. Solar cell efficiency is the beacon of photovoltaic technology innovation. Every 0.01% improvement in solar cell conversion efficiency requires enormous efforts. In particular, crystalline silicon solar cells account for nearly 95% of the current photovoltaic market, so the ultimate efficiency of crystalline silicon solar cells also shows the development potential and direction of the photovoltaic industry, which is of great significance in the entire photovoltaic industry,” said Li Zhenguo, founder and president of LONGi.
LONGi previously announced a milestone of 25.47% efficiency for these cells in March 2022.
News item from LONGi
Solarman says
“Every 0.01% improvement in solar cell conversion efficiency requires enormous efforts. In particular, crystalline silicon solar cells account for nearly 95% of the current photovoltaic market, so the ultimate efficiency of crystalline silicon solar cells also shows the development potential and direction of the photovoltaic industry, which is of great significance in the entire photovoltaic industry,” said Li Zhenguo, founder and president of LONGi.”
Interesting, the 26.81% efficiency off of a manufacturing line is impressive. This amount of solar harvest efficiency is pushing the theoritical 30% efficiency of silicon cell with the prospect of tandem or tri layered cells to grab more than 30% of the solar spectrum efficiency. There is more to the solar PV cell and final solar PV panel assembled product. In just the last 10 years so many new technologies have been implemented, the real World use experience will not be fully known for perhaps 20 years of actual in use of the product World wide. It is common for a manufacturer to give one at least a 25 year output specification of 80% up to 90% after 25 years of use and around 82% after 30 years in use as a warranty. This lends to confidence in the purchase of the product. (YET), one must also think about some of the technology being used like; shingling of solar PV cells and using conductive “adhesives” to assemble some panels. The wafer saws that allow thin wafers to be used as solar PV cells, but the thinner cells are more prone to cracking and loss of efficiency over years of heat/cold cycling or even mechanical stress on the solar PV cells in a panel, by being installed. The accelerated test cycles are fairly accurate on MTBF of solar PV cells, when one aggregates years of LID, PID, delta heating/cooling stresses on an assembled panel, then the longivity will be thoroughly tested over actual years of use. Depending on site of installation, hot dry deserts present stress problems as well as cold wet sites that can penetrate panel sealing and create corrosion that can degrade the panel below specifications in only a few years. Over the years introduction of Boron has lessened the effects of LID and PID to allow solar PV panels to have a linear degradition warrany of up to 30 years of use. The long term will determine if conductive adhesives, thin wafer cells and laser annealing will ameloriate cell degradation problems when these panels are actually in use for 30 years.