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Oxford Photovoltaics has been spun out of the University of Oxford to develop solar cell windows.
The rapid consumption of fossil fuel has caused unacceptable environmental problems such as the greenhouse effect, which may lead to disastrous climatic consequences. Now renewable and clean energy resources are definitely required in order to deal with such global energy and environmental issues. Nature harnesses solar energy with photosynthesis for its production tasks, and fossil fuel is the product of photosynthesis. Thus, it is highly desirable to develop artificial photosynthetic systems for the production of hydrogen or other fuels by exploiting and applying the basic chemistry of photosynthesis, hopefully in a more efficient manner than natural systems.
May The Berkley Lab at the University of California Berkley has come up with a new catalyst for splitting water. In fairness to readers, there have been other claims from out there that didn’t seem, well, practical.
A startup called Nanotune says its ultracapacitor technology could make electric cars cheaper and extend their range. The company, based in Mountain View, California, has developed a way to make electrodes that results in ultracapacitors with five to seven times as much storage capacity as conventional ones. Conventional ultracapacitors, which have the advantage of delivering fast bursts of power and can be recharged hundreds of thousands of times without losing much capacity, are too expensive and store too little energy to replace batteries.
Titre du document / Document title Auteur(s) / Author(s) Résumé / Abstract
Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, and Chemistry Department, Brookhaven National Laboratory, Upton, New York 11973-5000 J. Am. Chem. Soc. , 2010 , 132 (5), pp 1545–1557 DOI: 10.1021/ja904906v
(PhysOrg.com) -- Expanding on work published two years ago, MIT's Daniel Nocera and his associates have found yet another formulation, based on inexpensive and widely available materials, that can efficiently catalyze the splitting of water molecules using electricity. This could ultimately form the basis for new storage systems that would allow buildings to be completely independent and self-sustaining in terms of energy: The systems would use energy from intermittent sources like sunlight or wind to create hydrogen fuel, which could then be used in fuel cells or other devices to produce electricity or transportation fuels as needed. Nocera, the Henry Dreyfus Professor of Energy and Professor of Chemistry, says that solar energy is the only feasible long-term way of meeting the world’s ever-increasing needs for energy, and that storage technology will be the key enabling factor to make sunlight practical as a dominant source of energy.
Traditional homogeneous water oxidation catalysts are plagued by instability under the reaction conditions. We report that the complex [Co 4 (H 2 O) 2 (PW 9 O 34 ) 2 ] 10– , comprising a Co 4 O 4 core stabilized by oxidatively resistant polytungstate ligands, is a hydrolytically and oxidatively stable homogeneous water oxidation catalyst that self-assembles in water from salts of earth-abundant elements (Co, W, and P). With [Ru(bpy) 3 ] 3+ (bpy is 2,2′-bipyridine) as the oxidant, we observe catalytic turnover frequencies for O 2 production ≥5 s −1 at pH = 8. The rate’s pH sensitivity reflects the pH dependence of the four-electron O 2 -H 2 O couple.
Speaking at the National Meeting of the American Chemical Society in California, MIT professor Daniel Nocera claims to have created an artificial leaf, made from stable and inexpensive materials, which mimics nature's photosynthesis process. The device is an advanced solar cell, no bigger than a typical playing card, which is left floating in a pool of water. Then, much like a natural leaf, it uses sunlight to split the water into its two core components, oxygen and hydrogen, which are stored in a fuel cell to be used when producing electricity . Nocera's leaf is stable -- operating continuously for at least 45 hours without a drop in activity in preliminary tests -- and made of widely available, inexpensive materials -- like silicon , electronics and chemical catalysts.
One drinking- water bottle could provide enough energy for an entire household in the developing world if Dan Nocera has his way. A chemist from M.I.T. and founder of the company Sun Catalytix, Nocera has developed a cobalt-based catalyst that allows him to store energy the same way plants do: by splitting water. "Almost all the solar energy is stored in water splitting," Nocera told the inaugural ARPA-E conference on March 2.
MIT scientists are developing an alternative to photovoltaic and solar-thermal systems for capturing the sun's energy. Discovered decades ago, but largely undeveloped, the thermo-chemical approach captures solar energy in the configuration of certain molecules which can then release it on demand to produce usable heat. Unlike conventional solar-thermal systems, which even with effective insulation let the heat gradually leak away, the heat-storing chemicals can remain stable for years.
For 91 years, Nenana, a village of 450 people, 55 miles southwest of Fairbanks, has held a wager on the exact moment that the ice breaks up on the nearby Tanana River. The winners in 2007 shared a jackpot of $303,272. But for geophysicists, the historical record of Tanana's yearly thaw since 1917 is far more valuable as evidence of a longterm warming trend affecting lakes and rivers throughout the Northern Hemisphere. For example, researchers at the University of Wisconsin's Center for Limnology who analyzed newspaper archives, transport ledgers and religious records dating back to the 16th century found 17 lakes in Europe, Asia and the US with records going back 150 years.