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ENVIRONMENTALISTS AND EPA MOVING IN WRONG DIRECTION. MOST WIND FARMS ARE NOT PROVIDING ANY AFFORDABLE ENERGY AND 14,400 WIND GENERATORS HAVE BEEN ABANDONED IN THE US.

Technology Review has an article on advances in wind turbine technology - Better Wind Turbines. ExRo Technologies, a startup based in Vancouver, BC, has developed a new kind of generator that's well suited to harvesting energy from wind. It could lower the cost of wind turbines while increasing their power output by 50 percent. The new generator runs efficiently over a wider range of conditions than conventional generators do. When the shaft running through an ordinary generator is turning at the optimal rate, more than 90 percent of its energy can be converted into electricity. But if it speeds up or slows down, the generator's efficiency drops dramatically. This isn't a problem in conventional power plants, where the turbines turn at a steady rate, fed by a constant supply of energy from coal or some other fuel. But wind speed can vary wildly. Turbine blades that change pitch to catch more or less wind can help, as can transmissions that mediate between the spinning blades and the generator shaft. But transmissions add both manufacturing and maintenance costs, and there's a limit to how much changing the blade angle can compensate for changing winds.

Earlier this week, Portugal debuted the world's first commercial wave energy farm. Wave energy at the Agucadoura station is converted into electricity with the use of three red "sea-snakes", or cylindrical wave energy converters, that are attached to the seabed off Portugal's northern coast. Energy captured by the sea-snakes is carried to an undersea cable station, where it is then fed into the electrical grid.

An underwater turbine that generates electricity from tidal streams was plugged into the UK's national grid today. It marks the first time a commercial-scale underwater turbine has fed power into the network and the start of a new source of renewable energy for the UK.

Jerome a Paris has an excellent (and long) article at TOD about the economics of wind power - The cost of wind, the price of wind, the value of wind. I'd like to try to clear some of the confusion that surrounds the economics of wind power, as it is often fed and used by the opponents of wind to dismiss it. As I noted recently, even the basic economics of energy markets are often wilfully misunderstood by commentators, so it's worth going in more detail through concepts like levelised cost and marginal cost, and identify how different electricity producers have different impacts on electricity (market) prices (which may or may not be reflected in retail prices) and have different externalities. Value for society of a generation source may also include other items that are harder to acount in purely monetary terms (and/or whose very value may be disputed), such as the long term risk of depletion of the fuel, or energy security issues, such as dependency on unstable and/or unfriendly foreign countries or vulnerable infrastructure.

Effective replacement filter for countertop, gravity-fed water filter systems. Removes 99.9999% of all bacteria, 99.99% virus and pathogens; purifies 1/2 gallon non-salt water per minute.Works for Berkey, Doulton and AquaRain.

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