That they have the potential to produce cheaper electricity than coal-fired generators can
SUNLIGHT is free, but that is no reason to waste it. Yet even the best silicon solar cells—by far the most common sort—convert only a quarter of the light that falls on them. Silicon has the merit of being cheap: manufacturing improvements have brought its price to a point where it is snapping at the heels of fossil fuels. But many scientists would like to replace it with something fundamentally better.
John Rogers, of the University of Illinois, Urbana-Champaign, is one. The cells he has devised (and which are being made, packaged into panels and deployed in pilot projects by Semprius, a firm based in North Carolina) are indeed better. By themselves, he told this year’s meeting of the American Association for the Advancement of Science, they convert 42.5% of sunlight. Even when surrounded by the paraphernalia of a panel they manage 35%. Suitably tweaked, Dr Rogers reckons, their efficiency could rise to 50%. Their secret is that they are actually not one cell, but four, stacked one on top of another.
Solar cells are made of semiconductors, and every type of semiconductor has a property called a band gap that is different from that of other semiconductors. The band gap defines the longest wavelength of light a semiconductor can absorb (it is transparent to longer wavelengths). It also fixes the maximum amount of energy that can be captured from photons of shorter wavelength. The result is that long-wavelength photons are lost and short-wave ones incompletely utilised.
Dr Rogers gets round this by using a different material for each layer of the stack. He chooses his materials so that the bottom of the band gap of the top layer matches the top of the band gap of the one underneath, and so on down the stack. Each layer thus chops off part of the spectrum, converts it efficiently into electrical energy and passes the rest on.
The Latest on: Efficiency of solar cells
via Google News
The Latest on: Efficiency of solar cells
- Solar panel cleaningon May 27, 2022 at 6:25 am
Any wet leaves, debris or film on the surface of a solar panel can block incoming solar radiation and reduce efficiency. Most solar panels require at least annual cleaning, though cleaning them more ...
- Terbium-doped perovskite solar cell with 17.5% efficiencyon May 27, 2022 at 5:09 am
The device was also able to retain more than 90% of its initial efficiency after aging in 50% to 60% relative humidity for more than 500 hours. The researchers claim they were also able to build a ...
- Solar panels making farming more efficienton May 27, 2022 at 4:55 am
Agrivoltaics is the combination of farming and solar power, and it's a more efficient way to farm that's starting to become more popular across the country.
- JA Solar introduces n-type solar panel with 22.4% efficiencyon May 26, 2022 at 11:20 pm
JA Solar said the smallest solar panel in its new n-type product line has a power output of 435 W and a power conversion efficiency of 22.3%. The largest module in the series has an efficiency rating ...
- Highest Efficiency 1-Sun Solar Cellon May 24, 2022 at 3:00 pm
Researchers have created a solar cell with a record 39.5% efficiency under 1-sun global illumination. This is believed to be the highest efficiency solar cell of any type, measured using standard ...
- Scientists smash solar cell efficiency recordon May 24, 2022 at 5:00 am
Researchers have produced a world record in solar cell efficiency using real-world conditions. A team from the (NREL) used an innovative form of “quantum well” solar cell to achieve 39.5 per cent ...
- Scientists just broke the record for the highest efficiency solar cellon May 20, 2022 at 9:05 am
A team of researchers at the US Department of Energy's National Renewable Energy Laboratory has created a solar cell with a record efficiency of 39.5 percent under 1-sun global illumination.
- Quantum well solar cell clocks world record efficiency of almost 40%on May 19, 2022 at 8:43 pm
Researchers at the National Renewable Energy Laboratory (NREL) have broken the world record for solar cell efficiency. Reaching almost 40 percent, the new device boasts the highest efficiency recorded ...
- Researchers create highest efficiency 1-sun solar cellon May 19, 2022 at 8:50 am
Researchers at the U.S. Department of Energy's National Renewable Energy Laboratory (NREL) created a solar cell with a record 39.5% efficiency under 1-sun global illumination. This is the highest ...
- Solar cell achieves record-high efficiencyon May 18, 2022 at 12:16 pm
A solar cell developed by researchers at the National Renewable Energy Laboratory has achieved a record 39.5% efficiency under 1-sun global illumination.
via Bing News