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"Our new blog is designed to radically reduce the energy use associated with accessing our content. Low-tech Magazine was born in 2007 and has seen minimal changes ever since. Because a website redesign was long overdue - and because we try to practice what we preach - we decided to build a low-tech, self-hosted, and solar-powered version of Low-tech Magazine. The new blog is designed to radically reduce the energy use associated with accessing our content. Why a Low-tech Website? We were told that the Internet would "dematerialise" society and decrease energy use. Contrary to this projection, it has become a large and rapidly growing consumer of energy itself. In order to offset the negative consequences associated with high energy consumption, renewable energy has been proposed as a means to lower emissions from powering data centers. For example, Greenpeace's yearly ClickClean report ranks major Internet companies based on their use of renewable power sources."

"Abstract Many people believe renewable energy sources to be capable of substituting fossil or nuclear energy. However there exist very few scientifically sound studies, which apply due diligence to substantiating this impression. In the present paper, the case of photovoltaic power sources in regions of moderate insolation is analysed critically by using the concept of Energy Return on Energy Invested (ERoEI, also called EROI). But the methodology for calculating the ERoEI differs greatly from author-to-author. The main differences between solar PV Systems are between the current ERoEI and what is called the extended ERoEI (ERoEI EXT). The current methodology recommended by the International Energy Agency is not strictly applicable for comparing photovoltaic (PV) power generation with other systems. The main reasons are due to the fact that on one hand, solar electricity is very material-intensive, labour-intensive and capital-intensive and on the other hand the solar radiation exhibits a rather low power density."

"... Soil is the bedrock of civilization (Perlin 1991, Ponting 1993). Biofuels are not sustainable or renewable. Why would we destroy our topsoil, increase global warming, deplete and pollute groundwater, destroy fisheries, and use more energy than what's gained to make ethanol? Why would we do this to our children and grandchildren? Perhaps it's a combination of pork barrel politics, an uninformed public, short-sighted greedy agribusiness corporations, jobs for the Midwest, politicians getting too large a percent of their campaign money from agribusiness (Lavelle 2007), elected leaders without science degrees, and desperation to provide liquid transportation fuels (Bucknell 1981, Hirsch 2005). ..."

"In terms of energy conservation, the leaps made in energy efficiency by the infrastructure and devices we use to access the internet have allowed many online activities to be viewed as more sustainable than offline. On the internet, however, advances in energy efficiency have a reverse effect: as the network becomes more energy efficient, its total energy use increases. This trend can only be stopped when we limit the demand for digital communication."

"In terms of energy conservation, the leaps made in energy efficiency by the infrastructure and devices we use to access the internet have allowed many online activities to be viewed as more sustainable than offline. On the internet, however, advances in energy efficiency have a reverse effect: as the network becomes more energy efficient, its total energy use increases. This trend can only be stopped when we limit the demand for digital communication."

"El problema de las « energías renovables » (por Kim Hill)"

"El problema de las « energías renovables » (por Kim Hill)"

"La empresa belga Turbulent está apostando por usinas hidroeléctricas de pequeño porte para generar energía renovable con bajo impacto para el medio ambiente. En este sentido ellos desarrollaron una turbina de remolino que se puede instalar en ríos, arroyos y canales, aprovechando el agua corriente para generar energía para hasta sesenta casas. El objetivo de esta empresa belga es hacer la energía hidroeléctrica sostenible y aplicable a pequeña escala. A diferencia de las grandes represas, su turbina de baja presión requiere una diferencia de altura de tan solo un metro y medio para funcionar a toda capacidad. Probado en ríos en toda Bélgica, el dispositivo se puede ampliar para generar 15, 30 y hasta 100 kilovatios."

"El sistema energético actual, basado en la extracción y quema de recursos fósiles, ha alimentado a una sociedad global de producción y consumo en permanente expansión. Los impactos ambientales y la distribución desigual de costos sociales evidencian la in-sustentabilidad de este modelo. En este contexto ¿es suficiente transitar al uso expansivo de energías renovables para alcanzar un modelo más justo y sustentable? O bien ¿necesitamos repensar de manera sistémica nuestros proyectos de vida y desarrollo? ..."

"¿Quieres saber qué usos damos a la energía solar en nuestro planeta?Energía solar térmica.Energía solar fotovoltaica.Energía solar termoeléctrica."