The key to creating a material that would be ideal for converting solar energy to heat is tuning the material’s spectrum of absorption just right: It should absorb virtually all wavelengths of light that reach Earth’s surface from the sun—but not much of the rest of the spectrum, since that would increase the energy that is reradiated by the material, and thus lost to the conversion process.
A new report prepared by analysts from Lawrence Berkeley National Laboratory examines the...
A collaboration between scientists in the Univ....
Yale Univ. associate professor of electrical engineering Minjoo Larry Lee has been awarded $2,540,000 to develop dual-junction solar cells that can operate efficiently at extreme temperatures above 750 F. In addition to converting a portion of the sunlight directly into electricity, the solar cells will use the remainder of the light to heat high-temperature fluids that can drive a steam turbine or be stored for later use.
The price of solar energy in the U.S. continues to fall substantially, according to the latest editions of two annual reports produced by Lawrence Berkeley National Laboratory (Berkeley Lab). A third Berkeley Lab report, written in collaboration with researchers at Yale Univ., the Univ. of Texas at Austin and the DOE, shows that local permitting and other regulatory procedures can significantly impact residential photovoltaic prices.
The most familiar photovoltaic (PV) designs use rigid layers of silicon crystal, but recently inexpensive organic semiconductor materials have also been used successfully. At this time, organic PV devices are hindered by low efficiency, in part because quantifying their electrical properties is a challenge. Researchers have now developed a method that allows the prediction of the current density-voltage curve of a photovoltaic device.
Lighter, more flexible and cheaper than conventional solar-cell materials, carbon nanotubes (CNTs) have long shown promise for photovoltaics. But research stalled when CNTs proved to be inefficient, converting far less sunlight into power than other methods. Now a research team has created a new type of CNT solar cell that is twice as efficient as its predecessors.
A research team investigating an important cofactor in photosynthesis, a manganese-calcium complex which uses solar energy to split water into molecular oxygen, have determined the exact structure of this complex at a crucial stage in the chemical reaction. The new insights into how molecular oxygen is formed at this metal complex may provide a blueprint for synthetic systems that could store sunlight energy in chemical energy carriers.
A team of researchers at Michigan State Univ. has developed a new type of solar concentrator that when placed over a window creates solar energy while allowing people to actually see through the window. It is called a transparent luminescent solar concentrator and can be used on buildings, cell phones and any other device that has a clear surface.
This could be a classic win-win solution: A system proposed by researchers at Massachusetts Institute of Technology recycles materials from discarded car batteries—a potential source of lead pollution—into new, long-lasting solar panels that provide emissions-free power. The system is based on a recent development in solar cells that makes use of a compound called perovskite.
New Stanford Univ. research outlines the path to a possible future for California in which renewable energy creates a healthier environment, generates jobs and stabilizes energy prices. Among other metrics, the plan calculates the number of new devices and jobs created, land and ocean areas required, and policies needed for infrastructure changes.
A new material structure developed at Massachusetts Institute of Technology generates steam by soaking up the sun. The structure—a layer of graphite flakes and an underlying carbon foam—is a porous, insulating material structure that floats on water. When sunlight hits the structure’s surface, it creates a hotspot in the graphite, drawing water up through the material’s pores, where it evaporates as steam.
One of the major road blocks to the design and development of new, more efficient solar cells may have been cleared. Researchers with the Lawrence Berkeley National Laboratory have developed the first ab initio method for characterizing the properties of “hot carriers” in semiconductors. Hot carriers are electrical charge carriers with significantly higher energy than charge carriers at thermal equilibrium.
The solar panels that Idaho inventor Scott Brusaw has built aren't meant for rooftops. They are meant for roads, driveways, parking lots, bike trails and, eventually, highways. Brusaw, an electrical engineer, says the hexagon-shaped panels can withstand the wear and tear that comes from inclement weather and vehicles, big and small, to generate electricity.
Researchers at Princeton Univ. joined with experts at Liquid Light Inc. to devise an efficient method for harnessing sunlight to convert carbon dioxide into a potential alternative fuel known as formic acid. This type of acid is already being explored as an alternative in fuel cells. The new process takes place inside an electrochemical cell, which consists of metal plates the size of lunch-boxes that enclose liquid-carrying channels.
Despite five months of below-average temperatures and twice the normal amount of snowfall, NIST's Net-Zero Energy Residential Test Facility (NZERTF) in Washington, D.C. ended its one-year test run with 491 KW-h of extra energy. Instead of paying almost $4,400 for electricity, the experimental all-electric house actually earned a credit by exporting surplus energy to the local utility.
Experts don't fully understand how “plastic” solar panels work, which complicates the improvement of their cost efficiency and hinders wider use of the technology. However, an international team has now determined how light beams excite the chemicals in solar panels, enabling them to produce charge. Their findings were made possible with the use of femtosecond Raman spectroscopy.
Concentrating solar power (CSP) could supply a large fraction of the power supply in a decarbonized energy system, according to a new study of the technology and its potential practical application. For this research, scientists simulated the construction and operation of CSP systems in four regions around the world, taking into account weather variations, plant locations, electricity demand, and costs.
Rice Univ. scientists have created a one-step process for producing highly efficient materials that let the maximum amount of sunlight reach a solar cell. The Rice laboratory of chemist Andrew Barron found a simple way to etch nanoscale spikes into silicon that allows more than 99% of sunlight to reach the cells’ active elements, where it can be turned into electricity.
Los Alamos National Laboratory researchers have demonstrated an almost four-fold boost of the carrier multiplication yield with nanoengineered quantum dots. Carrier multiplication is when a single photon can excite multiple electrons. Quantum dots are novel nanostructures that can become the basis of the next generation of solar cells, capable of squeezing additional electricity out of the extra energy of blue and ultraviolet photons.
Researchers the world over are investigating solar cells which imitate plant photosynthesis, with the goal of using sunlight and water to create synthetic fuels such as hydrogen. Scientists in Switzerland have developed this type of photoelectrochemical cell, but this one recreates a moth’s eye to drastically increase its light collecting efficiency. The cell is made of cheap raw materials: iron and tungsten oxide.
Think those flat, glassy solar panels on your neighbor’s roof are the pinnacle of solar technology? Think again. Researchers at Univ. of Toronto have designed and tested a new class of solar-sensitive nanoparticle that outshines the current state of the art employing this new class of technology.
Wouldn’t it be nice to use solar- or wind-generated electricity to turn excess carbon dioxide into fuels and other useful chemicals? The process would store up the intermittent solar or wind energy in a form that could be used when and where it was needed, including in transportation applications, all while getting rid of some greenhouse gas.
Investigated heavily since the 1970s, solar cells have been the great unfulfilled promise for unlimited, almost free energy to power the world. The reasoning is solid: The Earth absorbs almost as much energy per hour than the entire human race uses in a single year.
A Swiss-made solar-powered aircraft has made a successful inaugural flight as its makers prepare for what they hope will be the first round-the-world solar flight. The aircraft spent 2 hours and 17 minutes in the air above western Switzerland early Monday. The Solar Impulse 2 is a bigger and better version of a single-seat prototype that first took flight five years ago and can theoretically stay airborne indefinitely.
Solar panels made in China have a higher overall carbon footprint and are likely to use substantially more energy during manufacturing than those made in Europe, said a new study from Northwestern Univ. and Argonne National Laboratory. The report compared energy and greenhouse gas emissions that go into the manufacturing process of solar panels in Europe and China.
Researchers are trying to develop solar-driven generators that can split water, yielding hydrogen gas that could be used as clean fuel. Such a device requires efficient light-absorbing materials that attract and hold sunlight to drive the chemical reactions involved in water splitting. Semiconductors are excellent light absorbers. However, these materials rust when submerged in the type of water solutions found in such systems.
Researchers at NIST have developed a laser-based instrument that generates artificial sunlight to help test solar cell properties and find ways to boost their efficiency. The novel NIST system simulates sunlight well across a broad spectrum of visible to infrared light. More flexible than conventional solar simulators, the laser instrument can be focused down to a small beam spot and shaped to match any desired spectral profile.
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