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Solar Panels Now Make More Electricity Than They UseAnd by 2020, the solar industry will have completely "paid back" the energy it took to produce the world's panels.Mobile solar panels at the Nellis Air Force Base in Nevada Nellis AFBSolar panels make energy, but they take energy to make, too. And, until about 2010 or so, the solar panel industry used more electricity than it produced, according to a new analysis. Now, the industry is set to "pay back" the energy it used by 2020.The study looked at what went into building and installing solar panels all over the world, including everything from home installations to solar farms, says Michael Dale, a climate and energy researcher at Stanford University, in a Stanford-produced video. He and a senior scientist, Sally Benson, thought that because the solar panel industry was growing so quickly, it might actually be using more electricity than it produced. Instead, they found an industry at a crux."I think that this paper shows that actually the industry is making positive strides and it's even in spite of its fantastically fast growth rates, it's still producing, or it's just about to start producing, a net energy benefit to society," Dale said.Most solar panels manufacturers now consume lots of electricity, usually pulled from coal or other fossil fuel-burning plants. Stanford News pointed to the example of melting silica rock to obtain the silicon used in most panels. The melting requires electricity to fire ovens to a temperature of about 3,000 degrees Fahrenheit.Solar panels' energy balance is now tipping, however, because newer technologies reduce that electricity consumption. For example, some newer panels require less silicon, or waste less material in the manufacturing process. Researchers are also looking to replace silicon with more abundant elements, such as copper, zinc, tin and carbon.Dale and Benson published their full analysis in the journal Environmental Science & Technology.
Que todo se ha hecho mal está claro, ahora se debería pensar en un programa de techos solares con subvenciones muy moderadas, apovechando que los costes de la FV han bajado tanto.
Cita de: Republik en Abril 04, 2013, 16:48:22 pmQue todo se ha hecho mal está claro, ahora se debería pensar en un programa de techos solares con subvenciones muy moderadas, apovechando que los costes de la FV han bajado tanto.Pero si es que ni hace falta, ni es deseable (todo lo que subvenciona el gobierno lo jode, a los hechos me remito). Apruebese de una puñetera vez el decreto que regula el balance neto, y no digo ya que lo escriba Greenpeace, pero conque con no lo escriban las eléctricas sino alguien medianamente neutral que vele por los intereses del país, y se llena España de tejados fotovoltaicos en un pispas. No hace falta poner un puto euro de subvenciones (si es caso, todo lo más, crédito a través del ICO o del sursuncorda, porque está el país más seco de liquidez que la mojama). ¡BALANCE NETO YA, HOSTIAS!
Cita de: TEOTWAIKI en Abril 04, 2013, 19:04:14 pmCita de: Republik en Abril 04, 2013, 16:48:22 pmQue todo se ha hecho mal está claro, ahora se debería pensar en un programa de techos solares con subvenciones muy moderadas, apovechando que los costes de la FV han bajado tanto.Pero si es que ni hace falta, ni es deseable (todo lo que subvenciona el gobierno lo jode, a los hechos me remito). Apruebese de una puñetera vez el decreto que regula el balance neto, y no digo ya que lo escriba Greenpeace, pero conque con no lo escriban las eléctricas sino alguien medianamente neutral que vele por los intereses del país, y se llena España de tejados fotovoltaicos en un pispas. No hace falta poner un puto euro de subvenciones (si es caso, todo lo más, crédito a través del ICO o del sursuncorda, porque está el país más seco de liquidez que la mojama). ¡BALANCE NETO YA, HOSTIAS!Es cierto, la clave realmente está ahí. Subvenciones ya ni testimoniales hacen falta. Pero con 107GW de planta instalada la mafia eléctrica no estará por la labor.
No seais inocentes. Más del cincuenta por ciento de la gasolina es impuesto. Sin ese impuesto nos vamos al guano pero de verdad. ¿Como queréis que haya coches eléctricos?
Game changer in alternative energyA team of Virginia Tech researchers has discovered a way to extract large quantities of hydrogen from any plant, a breakthrough that has the potential to bring a low-cost, environmentally friendly fuel source to the world.“Our new process could help end our dependence on fossil fuels,” said Y.H. Percival Zhang, an associate professor of biological systems engineering in the College of Agriculture and Life Sciences and the College of Engineering “Hydrogen is one of the most important biofuels of the future.”Zhang and his team have succeeded in using xylose, the most abundant simple plant sugar, to produce a large quantity of hydrogen that previously was attainable only in theory. Zhang’s method can be performed using any source of biomass.The discovery is a featured editor’s choice in an online version of the chemistry journal Angewandte Chemie, International Edition.This new environmentally friendly method of producing hydrogen utilizes renewable natural resources, releases almost no zero greenhouse gasses, and does not require costly or heavy metals. Previous methods to produce hydrogen are expensive and create greenhouse gases.The U.S. Department of Energy says that hydrogen fuel has the potential to dramatically reduce reliance of fossil fuels and automobile manufactures are aggressively trying to develop vehicles that run on hydrogen fuel cells. Unlike gas-powered engines that spew out pollutants, the only byproduct of hydrogen fuel is water. Zhang’s discovery opens the door to an inexpensive, renewable source of hydrogen.Jonathan R. Mielenz, group leader of the bioscience and technology biosciences division at the Oak Ridge National Laboratory, who is familiar with Zhang’s work but not affiliated with this project, said this discovery has the potential to have a major impact on alternative energy production.“The key to this exciting development is that Zhang is using the second most prevalent sugar in plants to produce this hydrogen,” he said. “This amounts to a significant additional benefit to hydrogen production and it reduces the overall cost of producing hydrogen from biomass.”Mielenz said Zhang’s process could find its way to the marketplace as quickly as three years if the technology is available. Zhang said when it does become commercially available, it has the possibility of making an enormous impact.Game changer in alternative energy“The potential for profit and environmental benefits are why so many automobile, oil, and energy companies are working on hydrogen fuel cell vehicles as the transportation of the future,” Zhang said. “Many people believe we will enter the hydrogen economy soon, with a market capacity of at least $1 trillion in the United States alone.”Obstacles to commercial production of hydrogen gas from biomass previously included the high cost of the processes used and the relatively low quantity of the end product.But Zhang thinks he has found the answers to those problems.For seven years, Zhang’s team has been focused on finding non-traditional ways to produce high-yield hydrogen at low cost, specifically researching enzyme combinations, discovering novel enzymes, and engineering enzymes with desirable properties.The team liberates the high-purity hydrogen under mild reaction conditions at 122 degree Fahrenheit and normal atmospheric pressure. The biocatalysts used to release the hydrogen are a group of enzymes artificially isolated from different microorganisms that thrive at extreme temperatures, some of which could grow at around the boiling point of water.The researchers chose to use xylose, which comprises as much as 30 percent of plant cell walls. Despite its abundance, the use of xylose for releasing hydrogen has been limited. The natural or engineered microorganisms that most scientists use in their experiments cannot produce hydrogen in high yield because these microorganisms grow and reproduce instead of splitting water molecules to yield pure hydrogen.To liberate the hydrogen, Virginia Tech scientists separated a number of enzymes from their native microorganisms to create a customized enzyme cocktail that does not occur in nature. The enzymes, when combined with xylose and a polyphosphate, liberate the unprecedentedly high volume of hydrogen from xylose, resulting in the production of about three times as much hydrogen as other hydrogen-producing microorganisms.The energy stored in xylose splits water molecules, yielding high-purity hydrogen that can be directly utilized by proton-exchange membrane fuel cells. Even more appealing, this reaction occurs at low temperatures, generating hydrogen energy that is greater than the chemical energy stored in xylose and the polyphosphate. This results in an energy efficiency of more than 100 percent — a net energy gain. That means that low-temperature waste heat can be used to produce high-quality chemical energy hydrogen for the first time. Other processes that convert sugar into biofuels such as ethanol and butanol always have energy efficiencies of less than 100 percent, resulting in an energy penalty.In his previous research, Zhang used enzymes to produce hydrogen from starch, but the reaction required a food source that made the process too costly for mass production.The commercial market for hydrogen gas is now around $100 billion for hydrogen produced from natural gas, which is expensive to manufacture and generates a large amount of the greenhouse gas carbon dioxide. Industry most often uses hydrogen to manufacture ammonia for fertilizers and to refine petrochemicals, but an inexpensive, plentiful green hydrogen source can rapidly change that market.“It really doesn’t make sense to use non-renewable natural resources to produce hydrogen,” Zhang said. “We think this discovery is a game-changer in the world of alternative energy.”
Endesa afirma que los precios del mercado eléctrico son "un espejismo" y ve "poca" colaboración del GobiernoEl director de regulación de Endesa, Juan José Alba, señaló que el precio cero marcado en el mercado mayorista de electricidad durante muchas horas es "un espejismo", porque no impide la generación de costes que luego se acaban cargando en el recibo de la luz, y criticó la "poca" colaboración con el Gobierno para desarrollar normativas energéticas.EFE - EUROPA PRESS MADRID 10 · 04 · 2013 Durante las jornadas "Asuntos clave de la energía en Europa", organizadas por Enerclub, Alba aludió a la "situación bastante peculiar" en el "pool" durante los últimos días, en los que se registraron "muchas horas" de precio cero. Esta circunstancia se debe a que la generación nuclear, hidráulica y eólica, que suelen entrar a precio cero, son suficientes para cubrir toda la demanda durante varias horas.El director de regulación de Endesa explicó que esto "no deja de ser un espejismo" ya que la mayor entrada de renovables encarece las primas reguladas, al tiempo que la ociosidad de los ciclos de gas requiere también un pago por capacidad, lo que eleva el coste de la electricidad en España.Ayer, el secretario de Estado de Energía, Alberto Nadal, afirmó que el Ministerio de Industria trabaja en una revisión del mercado mayorista de electricidad para adaptarlo a la situación económica y energética actual."Lo que en primera instancia parece más barato, al final nos acabamos encontrando con un resultado más caro derivado de la coexistencia de objetivos que no hemos sido capaces de encajar adecuadamente", señaló el director de regulación de Endesa, que también reconoció que hay poca colaboración con el Gobierno."En estos momentos, el grado de negociación del Gobierno con el sector eléctrico y los usuarios en el desarrollo de políticas no es muy elevado. Colaboración hay poca", afirmó.El directivo de Endesa también cuestionó el "invento español" del déficit de tarifa, deuda generada al ser los ingresos vía recibo de la luz insuficientes para cubrir los costes del sistema."Se genera una deuda que acabarán pagando a plazos los consumidores que además no reciben señal de precio adecuada, puesto que perciben que el consumo de energía es más barato de lo que es. Eso no es lo mejor para la eficiencia", argumentó.