EoW November 2010

Transat lant ic Cable

From the results of a member survey by the Washington-based trade group, that is nearly asmuch as the amount of wind capacity that was actually built in the same year. Eliminating turbine clutter on radar is challenging. Ms Broydo ❈ Vestel observed that many radar systems in use in the United States date back to the 1950s and have outmoded processing capabilities – “in some cases, less than those of a modern laptop computer.” She wrote, “While there are technology xes to ease interference on these aging systems, it can be tricky to lter out just the turbines.” Gary Seifert characterises the radar-wind energy clash as “the train wreck of the 2000s.” The researcher with the Idaho National Laboratory, an Energy Department facility, told the Times , “The train wreck is the competing resources for two needs: energy security and national security.” Canada is quietly carving out a speciality in the use of industrial robots for the inspection of overhead high-voltage transmission lines, an operation ordinarily (and expensively) performed from a helicopter, through binoculars. Canadian utilities are experimenting with line-crawling robots to monitor aging 1970s-era transmission infrastructure for wear and tear and other hazardous conditions. (Let it be remembered that an overhanging tree branch triggered the massive Northeast Blackout of 2003.) An article in the Toronto Star reported on the midsummer inspection of transmission lines crossing the St Lawrence River. “Each 735-kilovolt line carries a powerful punch,” wrote Tyler Hamilton. “So getting close enough to these live wires can be tricky – and potentially deadly if mistakes are made.” But not for the two robots engaged in the inspection project overseen by Hydro-Québec, a provincial utility and one of the biggest electricity producers in North America. A typical stint for the robots, on the job for two weeks to that point, was ve to sixhours aday, duringwhicheachof them inspectedsix kilometres of line. (“A High-Wire Act for Robots,” 1 st August) The battery-powered LineScout – in use by developer Hydro- Québec since 2006 and by BC Hydro [an electric utility in the province of British Columbia] since 2008 – overcame the inability of an earlier model to move past transmission towers and hop onto and o di erent lines. It is waterproof, equipped with four cameras, packed with sensors that can detect such problems as corrosion, and capable of working in extreme temperatures. As described by Mr Hamilton, it hangs from the line “like a mechanical sloth on roller skates.” Serge Montambault, a manager of the St Lawrence crossings project, told the Star that inspection used to require that “hot” transmission lines be de-energised – disconnected temporarily from the grid. But rising demand for electricity argues against taking lines out of service. Now, he said, “They can send the robot to do the live-line inspection, bring back high-quality images and data, then let an engineer on the ground decide if repairs are necessary.” Canadian advances in mobile robotics enable safer and more economical inspection of overhead power lines

Energy

Air power meets wind power – and a formerly blameless green-energy technology comes under suspicion

Scepticism of e orts to generate electricity from wind power tends to centre on unreliability (when the wind dies down, so does the windmill) and unsightliness: no vista, onshore or o , is enhanced by a“wind farm”of steel turbines with vanes as tall as 400 feet. No one has been heard to impugn the virtue of a non- polluting technology which seeks to reap value from a renewable source free to all. The United States Air Force asserts that moving wind turbine blades can mimic airplanes on many radar systems and even cause planes to disappear from radar screens altogether; also that clusters of turbines can create false storm activity on weather radar, making it harder for air tra c controllers to give accurate weather information to pilots. Accordingly, the Air Force has declared wind turbines a danger to its operations and called for the removal of thousands of them now standing in the Tehachapi Mountains that skirt the Mojave Desert in southern California. Writing from Barstow, California, in the New York Times , Leora Broydo Vestel pointed out that this indictment of wind turbines has important support in Washington. In March, Dr Dorothy Robyn, Deputy Under Secretary of Defense (Installations and Environment), told a congressional subcommittee that the turbines pose an unacceptable risk to training, testing and national security in certain regions. While the military has not ascribed any serious incidents to this cause, the Defense Department has emerged as a strong opponent of wind projects. This stance puts Defense in direct opposition to another branch of the federal government, the Energy Department, which is spending billions on wind projects as part of President Barack Obama’s e ort to promote renewable energy. Collisions between military and industry have occurred elsewhere in the country but appear to be most frequent in California and Nevada. There, as noted by the Times , the Air Force, Army and Navy control 20,000 square miles of airspace and associated land used for bomb tests; low-altitude, high-speed air manoeuvres; and radar testing and development. The impact of wind turbines on radar, which the Times said “had been a back-burner concern for years,” is now very much to the forefront for rms in the Mojave area thwarted by opposition from the military to wind-powered electrical generators. Ms Broydo Vestel wrote, “Horizon Wind Energy recently withdrew three project applications. AES Wind Generation said it found out in May, after nine years of planning, that the military had objections to its proposal to build an 82.5-megawatt, 33-turbine wind farm.” (“Wind Turbine Projects Run Into Resistance,” 26 th August). According to the AmericanWind Energy Association, in 2009 about 9,000 megawatts of proposed wind projects were abandoned or delayed because of radar concerns raised by the military and the Federal Aviation Administration. Until now, that is.

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EuroWire – November 2010