To Operate In Cold Places Like Canada, Heating Can Be Applied To Some Essential Components Of Turbines, Such As Motor And Gears
At the main U.S. research station in Antarctica, annual temperatures average zero degrees Fahrenheit, but often drop much lower. There, near the United States’ McMurdo Station, a few wind turbines can provide enough electricity to power 100 American homes, and avoid burning over 120,000 gallons of diesefuel each year. This is no surprise. Wind turbines, cleverly designed from airplane wings, provide reliable, ever-cheaper energy that doesn’t emit deadly air pollution and planet-warming greenhouse gases into the atmosphere. Such lofty turbines were far from responsible for Texas’ disastrous energy collapse following a well-predicted surge of Arctic air into the region (it was largely a failure of gas power plants and infrastructure along with an ill-equipped, vulnerable grid). Yet, grossly irresponsible reporting inaccurately blamed a “MASSIVE GREEN ENERGY FAILURE,” specifically Texas’ over 13,000 wind turbines, for the historic collapse.
The reality about wind turbines, however, is they regularly operate in frigid conditions and can be weatherized to perform in wintry extremes. That’s why they work in places like Sweden, Antarctica, and Iowa (over 40 percent of Iowa’s electricity comes from wind). At times, some turbines (particularly those that aren’t weatherized like many in Texas) are temporarily shut down during excessively icy conditions, wherein other energy sources, be it nuclear, solar, gas, or hydropower, are meant to pick up the slack. And just like solar, nuclear, and hydropower, wind energy is one important contributor to a greater energy system — a system that’s gradually growing more efficient, more reliable, and clean. Sure, some turbines today aren’t weatherized and the wind doesn’t always blow, but that’s well known. That’s OK. “That’s normal. We’ve thought of solar and wind as part of our overall supply of electricity,” said Grant Goodrich, the executive director of the Great Lakes Energy Institute at Case Western Reserve University, which operates and researches wind turbines.
Working in the cold
Wind energy will continue to expand in the United States. That’s because in the U.S. money talks, and the prices of wind turbines have plunged. What’s more, wind energy doesn’t come with the cost and risk of transporting fossil fuels through hundreds of miles of pipelines, and the realistic potential for massive leaks and grim explosions. “The economics are there,” emphasized Gavin Dillingham, the energy director at the Houston Advanced Research Center, an energy research organization in Texas. Solar and wind are often cheaper than natural gas, added Dillingham, who is also the director of the U.S. Department of Energy’s Southcentral and Upper West Combined Heat and Power Technical Assistance Partnership, which works to improve the region’s energy efficiency and resilience. When accounting for weather extremes, the engineering is there, and improving, too. To operate in cold places like Canada, heating can be applied to some essential components of the turbines, such as the motor and gears.
“Cold climate weatherized wind turbines are not rocket science,” explained Vijay Modi, a professor of mechanical engineering at Columbia University’s School of Engineering and Applied Science. However, weatherizing turbines adds costs, perhaps less than 10 percent of the price of a new turbine, he said. And during freezing events, some wind energy is then diverted to warming the turbines. “The electricity output of the turbine reduces slightly when heating elements that prevent freeze-up kick in,” said Modi. “But this is a very small reduction in turbine output considering that otherwise you risk having no output at all.” A current area of turbine innovation today, however, is not how to just deal with the cold, but what to do with ice (which is caused by moist and freezing weather conditions). “Temperature really isn’t the important factor for operating the turbine,” said Goodrich. “The issue is ice formation on the blades.” Lots of ice accumulation on the blades can make them too heavy to productively, or safely, spin.
Developing ice-resistant coatings for big turbine blades is an ongoing, important area of research, explained Hui Hu, the director of the Aircraft Icing Physics and Anti-/De-icing Technology Laboratory at Iowa State University. Coatings (made with chemicals intended to repel water droplets) are ideal because they don’t require energy to heat up the blades, said Hu. Yet warming the blades might be a viable option, too. In Sweden, the power company Skellefteå Kraft has started both heating a carbon fiber layer on blades and circulating warm air inside the blades.
Wind turbines, of course, aren’t the only energy infrastructure that should be weatherized for the potential of extreme temperatures. After wintry extremes led to major outages in Texas and New Mexico in 2011, the Federal Energy Regulatory Commission recommended making Texas’ electrical infrastructure — including gas plants, gas pipelines, wind turbines, and transmission lines — winter-ready, such as by insulating pipes. This didn’t happen. As a result, cold weather (which Texas knew was coming) just collapsed large swathes of the grid. Misery and death ensued.
“The whole infrastructure was comprised because the state did not take the appropriate steps to weatherize its infrastructure,” said the Houston Advanced Research Center’s Dillingham, noting that the shutdown of gas plants was the greatest factor in Texas’ grid failure. In the coming decade, and beyond, wind power will be bolstered by the ability to store excess energy in batteries. This will provide more reliable renewable energy when, for example, some turbines might be less productive. “We need to build [wind farms] with storage in mind,” said Goodrich. Battery storage costs plunged by nearly 70 percent between 2015 and 2018, according to the U.S. Energy Information Administration. As wind energy is set to multiply across the nation, Modi emphasizes that it’s wise to consider weatherizing more wind turbines. The wind is free, and our ability to expertly harness energy from air currents still impresses even mechanical engineers.
This news was originally published at Mashable