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Princeton’s nanomesh nearly triples solar cell efficiency

There is huge potential in solar power. The sun is a giant ball of burning hydrogen in the sky, and it’s going to be sticking around for at least a few more billion years. For all intents and purposes, it’s a free source of energy. Sadly, humanity hasn’t been very good at harnessing its power directly. Our current methods of capturing the sun’s energy are very inefficient. For example, modern silicon and indium-tin-oxide-based solar cells are approaching the theoretical limit of 33.7% efficiency. Led by Stephen Chou, the team has made two dramatic improvements: reducing reflectivity, and more effectively capturing the light that isn’t reflected. PlaCSH is also capable of capturing a large amount of sunlight even when the sunlight is dispersed on cloudy days, which results in an amazing 81% increase in efficiency under indirect lighting conditions when compared to conventional organic solar cell technology. The gold mesh that sits on top is incredibly small. Related:  Clean EnergyEnergySolar

Solar Energy: Stanford scientists build the first all-carbon solar cell The Bao group's all-carbon solar cell consists of a photoactive layer, which absorbs sunlight, sandwiched between two electrodes. (Photo: Mark Shwartz / Stanford University) inShare6 October 31, 2012 By Mark Shwartz Stanford University scientists have built the first solar cell made entirely of carbon, a promising alternative to the expensive materials used in photovoltaic devices today. "Carbon has the potential to deliver high performance at a low cost," said study senior author Zhenan Bao, a professor of chemical engineering at Stanford. Unlike rigid silicon solar panels that adorn many rooftops, Stanford's thin film prototype is made of carbon materials that can be coated from solution. The coating technique also has the potential to reduce manufacturing costs, said Stanford graduate student Michael Vosgueritchian, co-lead author of the study with postdoctoral researcher Marc Ramuz. "Processing silicon-based solar cells requires a lot of steps," Vosgueritchian explained.

Breakthrough iron-based superconductors set new performance records (—The road to a sustainably powered future may be paved with superconductors. When chilled to frigid temperatures hundreds of degrees Celsius below zero, these remarkable materials are singularly capable of perfectly conducting electric current. To meet growing global energy demands, the entire energy infrastructure would benefit tremendously from incorporating new electricity generation, storage, and delivery technologies that use superconducting wires. But strict limits on temperature, high manufacturing costs, and the dampening effects of high-magnetic fields currently impede widespread adoption. Now, a collaboration led by scientists at the U.S. Department of Energy's Brookhaven National Laboratory have created a high performance iron-based superconducting wire that opens new pathways for some of the most essential and energy-intensive technologies in the world. Iron-based superconductors, however, are mechanically semi-metallic and therefore considerably less fragile.

V3Solar | The Most Efficient Energy Under The Sun engineer helps pioneer flat spray-on optical lens Kenneth Chau is excited about the newly published research that explains how he and his colleagues developed a negative-index material that can be sprayed onto surfaces and act as a lens. A team of researchers, including a University of British Columbia engineer have made a breakthrough utilizing spray-on technology that could revolutionize the way optical lenses are made and used. Kenneth Chau, an assistant professor in the School of Engineering at UBC’s Okanagan campus,worked with principal investigator Henri Lezec and colleagues Ting Xu, Amit Agrawal, and Maxim Abashin at the National Institute of Standards and Technology in Maryland on the development of a flat lens. Their work is published in the May 23 issue of the journal Nature. Nearly all lenses – whether in an eye, a camera, or a microscope – are presently curved, which limits the aperture, or amount of light that enters. “Curved lenses always have a limited aperture,” he explains. NB: An image of Prof.

Free Energy and Free Thinking Food versus Fuel: Native Plants Make Better Ethanol A mix of perennial grasses and herbs might offer the best chance for the U.S. to produce a sustainable biofuel, according to the results of a new study. But making that dream a reality could harm local environments and would require developing new technology to harvest, process and convert such plant material into biofuels such as ethanol. Biofuels have become controversial for their impact on food production. The ethanol used in the U.S. is currently brewed from the starch in corn kernels, which has brought ethanol producers (and government ethanol mandates) into conflict with other uses for corn, such as food or animal feed. To see if nonfood plants could be a source of a biofuel the way corn is, researchers followed six alternative crops and farming systems in so-called marginal lands over 20 years, including poplar trees and alfalfa. Turning marginal lands into biofuel farms could also have a negative impact on the local environment. Sprinkled nanocubes hold light tight Cristian Ciraci Scattering silver nanocubes over a metallic film may help harvest the sun's rays. Just sprinkle on and harvest light — that is the procedure with nanoscale cubes of silver that could be used to make efficient solar panels, heat detectors and specialist cameras. The cubes are scattered randomly on a piece of polymer-coated metal to form a device that absorbs nearly all the light that hits it. The material, which can be tuned to ensnare the desired wavelength of light, is described today in Nature1. Trapped in a gap Absorbers that can capture all, or almost all, of the light that hits them are typically made with metamaterials — materials engineered to have particular properties not found in nature. These minuscule components are painstakingly fabricated in a laborious, expensive etching process using lithography, so the light absorbers are difficult to make in large quantities. Smith and his team took a different approach. Different wavelengths