Sunday, October 7, 2018
During the first century, transition to wind power is worse than coal and gas, a new US research report shows. The report, conducted by researchers at Harvard University, shows that if the United States received all the electricity from wind turbines, the temperature in the country would have increased by + 0.24 degrees Celsius, up to + 1.5 degrees at night. + 0.54 Celsius around the wind farms. This would have more than eaten the benefits of decarbonizing the country’s power sector, which is intended to give a profit of – 0.1 Celsius. However, some places on the east coast will experience lower temperatures. In addition, the wind farms will occupy five to 20 times more area than previously thought, which will seize about a third of the United States.
Will take 100 years to achieve environmental benefits It will take around 100 years of wind power before the benefits begin to outweigh the disadvantages, researchers conclude, no matter how much of the energy wind power takes. “The reason is that the climate impacts of wind power instantly enter, while the benefits of reduced emissions accumulate slowly,” says physics professor David W. Keith to The Harvard Gazette, adding that “there is no free lunch.” “If the perspective is ten years, wind power in some aspects has more impact on the climate than coal and gas,” he says. “If the perspective is a thousand years, wind power is hugely much cleaner,” Keith says. – Affects the climate Keith further explains in an article in the Joule magazine that wind turbines, in addition to making power, also change the air movements in the atmosphere. The turbines mix the air layers close to the ground with the slightly higher in the atmosphere, while extracting energy from the wind. Normally the air is more quiet at night where cold air is close to the ground while the air is warmer higher up. Therefore, the effect is particularly noticeable at night. The turbines move more of the hot air down to the ground. In addition, they make a “windshadow” behind, where the wind is weaker, and the consequences of this are not fully investigated. In any case, the wind farms become less efficient the bigger they become. Around individual wind turbines, the effect is negligible, but the case becomes completely different when there are thousands of them. Previously, the study shows ten other cases where higher temperatures are detected locally around the wind farms.
– Redistributes heat into the atmosphere – The wind turbines redistribute heat and humidity into the atmosphere, which affects the climate. We have tried to make models for this on a continental scale, Keith says. The more wind turbines placed in the same place, the less efficient they become, especially if the wind farms span several kilometers. In addition, more of them will have to be placed in more windy places when the most attractive areas are filled up. This is something that has not been taken into account in previous studies, Keith and his research colleague Lee Miller believe. Refuses climate impact Critics of the report believe that Keith and Miller really talk about your local temperature rather than global warming. In particular, the American Wind Energy Association, AWEA, is in the throat of the report, which believes that climate change is not at all the only baking temperatures. – Keith and Miller’s analysis explores an excessively high level of wind turbine deployment and the effect it can have at higher local temperatures. However, they have not found that wind power leads to global warming, nor to the cascade of side effects and self-reinforcing effects we get from carbon pollution, writes communications advisor Greg Alvarez. Keith emphasizes that the report is not meant to be a fundamental criticism of wind power. “The work should also be seen as the first step in looking more seriously at the consequences of increased use of renewable energy sources,” he said. To the Technology Review magazine, powered by MIT, he believes that the world should perhaps support more against solar cell technology and invest less on wind power.