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"Generating electricity is not only inefficient, it also makes pedal power less sustainable, less robust and more costly. To begin with, batteries have to be manufactured, and they have to be replaced regularly. This requires energy, which can completely negate the ecological advantage of pedal power. According to this research paper (pdf), the embodied energy of a 150Wh lead-acid battery (like the one offered with the Windstream pedal power generator) is at least 37,500 Wh, which equals 250 full charges of the battery (more sources: 1/2). In other words: if you can deliver 75 watts of power to the battery, you have to pedal for 500 hours in order to generate the energy that was needed to manufacture the battery. Because the life expectancy of a lead-acid battery can be as low as 300 discharge/charge cycles (sources: 1/2), you are basically pedalling to produce the energy required to manufacture the battery. If you also factor in the embodied energy of other electronics and parts, the ecological advantage of a pedal powered generator connected to a battery becomes rather doubtful. It might costs more energy than it delivers."

"Generating electricity is not only inefficient, it also makes pedal power less sustainable, less robust and more costly. To begin with, batteries have to be manufactured, and they have to be replaced regularly. This requires energy, which can completely negate the ecological advantage of pedal power. According to this research paper (pdf), the embodied energy of a 150Wh lead-acid battery (like the one offered with the Windstream pedal power generator) is at least 37,500 Wh, which equals 250 full charges of the battery (more sources: 1/2). In other words: if you can deliver 75 watts of power to the battery, you have to pedal for 500 hours in order to generate the energy that was needed to manufacture the battery. Because the life expectancy of a lead-acid battery can be as low as 300 discharge/charge cycles (sources: 1/2), you are basically pedalling to produce the energy required to manufacture the battery. If you also factor in the embodied energy of other electronics and parts, the ecological advantage of a pedal powered generator connected to a battery becomes rather doubtful. It might costs more energy than it delivers."

"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."

"Because energy fuels both human development and environmental damage, policies that encourage energy demand reduction can run counter to policies for alleviating poverty, and the other way around. Achieving both objectives can only happen if energy use is spread more equally across societies. However, while it's widely acknowledged that part of the global population is living in 'energy poverty', there's little attention given to the opposite condition, namely 'energy excess' or 'energy decadence'. Researchers have calculated minimum levels of energy use needed to live a decent life, but what about maximum levels? "

Ambicioso proyecto de educación estadounidense sobre el clima, energía y educación ambiental. The Climate Literacy and Energy Awareness Network (CLEAN) Portal was launched in 2010 as a National Science Digital Library (NSDL) Pathways project. It is led by the science education expertise of the Cooperative Institute for Research in Environmental Science (CIRES) at the University of Colorado Boulder and the Science Education Resource Center (SERC) at Carleton College. As of 2012, CLEAN has been syndicated to NOAA's climate.gov portal. CLEAN's primary effort is to steward the collection of climate and energy science educational resources and to support a community of professionals committed to improving climate and energy literacy. The three key components of the CLEAN project are: The CLEAN Collection of Climate and Energy Science resources- high-quality, digital resources---including learning activities, visualizations, videos, and short demonstrations/experiments---geared toward educators of students in secondary through undergraduate levels. Guidance in Teaching Climate and Energy Science pages designed to help educators understand and be equipped to teach the big ideas in climate and energy science. The CLEAN Network a community of professionals committed to improving climate and energy literacy.

"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."

"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."

"Imagine you could use any kind of small head difference in a river or canal. The power those drops contain might surprise you. We created a technology that can make use of all these small waterfalls or rapids in a way that's safe for the environment. Gone are the days that communities had to choose between having power or fish to eat. Our robust and fish friendly vortex turbiness will generate energy 24/7 at an incredibly low cost of energy. That way you can have a project with high return on investment that improves the world just that little bit. Now, if you look at a river or canal, you'll notice that it's full of these small cascades, that's how nature builds rivers. We have created a distributed turbine system that can combines a large amount of turbines into one big virtual hydropower powerplant. These virtual hydropower plants can be as large as 10MW in power output. That's the power production of a small city! We can do this because our civil structures are designed to be easy to install, and the electronics and robust power take-offs are designed to keep working with minimal maintenance. The energy produced can be directly connected to your appliances or machinery, and at the same time connected to the national distribution grid, so you can inject the unused power to it, maximizing the revenue through a net billing connection."

"Today, getting what you need is as easy as a trip to the store. From food to clothing, energy, medicine, and so much more, Andy George will discover what it takes to make everything from scratch. His mission is to understand the complex processes of manufacturing that is often taken for granted and do it all himself. Each week he's traveling the world to bypass the modern supply chain in order to harvest raw materials straight from the source. Along the way, he's answering the questions you never thought to ask."

"Today, getting what you need is as easy as a trip to the store. From food to clothing, energy, medicine, and so much more, Andy George will discover what it takes to make everything from scratch. His mission is to understand the complex processes of manufacturing that is often taken for granted and do it all himself. Each week he's traveling the world to bypass the modern supply chain in order to harvest raw materials straight from the source. Along the way, he's answering the questions you never thought to ask."

¿Qué es un esclavo energético? ¿cómo nos afecta y por qué? el pensamiento de Buckminster Fuller en comic

"El pasado 25 de septiembre, Nate Hagens envía un mensaje al grupo de reflexión sobre la transición energética que dirige Ugo Bardi, llamado Energy Transition, donde existe una gran mayoría de personas que creen en una solución, al menos parcial, para el futuro de la Humanidad, con energías renovables. Lo que ahora transcribo a continuación, traducido al castellano, para los lectores de Crisis Energética y de la revista 15/15\15, con el permiso de Nate Hagens y de Ugo Bardi es el intercambio de opiniones que se ha producido. Espero con ello contribuir a profundizar el debate sobre nuestro futuro energético, donde sigue habiendo toda una amplia gama de posturas, desde los muy pesimistas y apocalípticos hasta los muy optimistas y creyentes en las modernas energías renovables, pasando por una variedad de posturas intermedias, que moderan ambos extremos. El intercambio, para resumirlo en lo posible, comienza con una comunicación de Nate a Ugo en el correo de energytransition, que Ugo o el grupo responden entre líneas como sigue:"

"New scientific research is quietly rewriting the fundamentals of economics. The new economic science shows decisively that the age of endlessly growing industrial capitalism, premised on abundant fossil fuel supplies, is over. The long-decline of capitalism-as-we-know-it, the new science shows, began some decades ago, and is on track to accelerate well before the end of the 21st century. With capitalism-as-we-know it in inexorable decline, the urgent task ahead is to rewrite economics to fit the real-world: and, accordingly, to redesign our concepts of value and prosperity, precisely to rebuild our societies with a view of adapting to this extraordinary age of transition."

"... 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). ..."

"... Así lo concluye un estudio publicado este lunes en la revista científica Nature Energy. Realizado por un equipo de investigación de la Universidad de Leeds, combinaron los datos de la Unión Europea y del Banco Mundial para calcular la distribución de las huellas energéticas y conocer en qué bienes y servicios de alto consumo energético tienden a gastar su dinero los diferentes grupos de ingresos. En total, se analizaron 86 países, desde los muy industrializados hasta los que están en vías de desarrollo, revelando una extrema disparidad en los resultados, tanto dentro de los países como a nivel mundial. A medida que aumentan los ingresos, apunta el estudio, la gente gasta más de su dinero en bienes de alto consumo energético, como paquetes de vacaciones o vehículos, lo que conduce a una gran desigualdad energética. En este sentido, los autores hallaron que el 10% más rico de los consumidores utiliza 187 veces más energía de combustible para vehículos que el 10% más pobre. ..."

"El ocaso del petróleo: Edición de 2015 En el último informe anual de la Agencia Internacional de la Energía (AIE), el World Energy Outlook (WEO) edición de 2015 (informe que ya comentamos in extenso en este blog) tuvimos la suerte de que la AIE nos dejara una tabla numérica sobre la evolución de la producción de hidrocarburos líquidos (lo que en un abuso de notación hace años que denomina "petróleo" o "todos los líquidos del petróleo") prevista para los próximos 25 años de acuerdo con su escenario central. Es la Tabla 3.5, que reproduzco aquí debajo"

"The cryptocurrency uses as much CO2 a year as 1m transatlantic flights. We need to take it seriously as a climate Bitcoin's electricity usage is enormous. In November, the power consumed by the entire bitcoin network was estimated to be higher than that of the Republic of Ireland. Since then, its demands have only grown. It's now on pace to use just over 42TWh of electricity in a year, placing it ahead of New Zealand and Hungary and just behind Peru, according to estimates from Digiconomist. That's commensurate with CO2 emissions of 20 megatonnes - or roughly 1m transatlantic flights."

"Industrial Ecology: Some Directions for Research May 1997 - Pre Publication Draft Prepared by: Iddo K. Wernick and Jesse H. Ausubel Program for the Human Environment, The Rockefeller University with the Vishnu Group for the Office of Energy and Environmental Systems, Lawrence Livermore National Laboratory"

"Carbon dioxide (CO2) is a gas essential for life- animals exhale it, plants sequester it. It exists in Earth's atmosphere in comparably small concentrations, but is vital for sustaining life. CO2 is termed a greenhouse gas (GHG) - a gas which absorbs and emits thermal radiation creating the 'greenhouse effect'. Along with other greenhouse gases, such as nitrous oxide and methane, CO2 is important in sustaining a habitable temperature for the planet: if there were absolutely no GHGs, our planet would be simply too cold. It has been estimated that without these gases, the average surface temperature of the Earth would be about -18 degrees celcius.1 Since the Industrial Revolution, however, energy-driven consumption of fossil fuels has led to a rapid increase in emissions of CO2, disrupting the global carbon cycle and leading to a planetary warming impact. As an international community, UN member parties have set a target of limiting average warming to 2 degrees celcius above pre-Industrial temperatures."

"Our core ecological problem is not climate change. It is overshoot, of which global warming is a symptom. Overshoot is a systemic issue. Over the past century-and-a-half, enormous amounts of cheap energy from fossil fuels enabled the rapid growth of resource extraction, manufacturing, and consumption; and these in turn led to population increase, pollution, and loss of natural habitat and hence biodiversity. The human system expanded dramatically, overshooting Earth's long-term carrying capacity for humans while upsetting the ecological systems we depend on for our survival. Until we understand and address this systemic imbalance, symptomatic treatment (doing what we can to reverse pollution dilemmas like climate change, trying to save threatened species, and hoping to feed a burgeoning population with genetically modified crops) will constitute an endlessly frustrating round of stopgap measures that are ultimately destined to fail."

"Un mundo virtual en el que debes ir realizando acciones para fomentar las energías renovables y tomar decisiones sobre distintos elementos para intentar mantener un equilibro ambiental, a la vez que energético y social. Este juego ha sido desarrollado por WWF España y Fundación AXA para concienciar y fomentar un cambio de modelo energético que nos permita mitigar los efectos del Cambio Climático."