The source of energy for driving wind turbines is the wind, and in this context, it is important to remember the first law of thermodynamics, which states that energy cannot be created or destroyed, only transformed from one form to another. Wind is not exempt from the laws of physics; therefore, if the available energy from the wind is reduced by wind turbines, the energy remaining in the wind is less for performing other functions, such as moving, dissipating, and mixing heat and moisture in the atmosphere.
Based on the above, there seems to be no basis for wind power generation to be termed “renewable.” There is no magic that restores or renews the energy lost to wind turbines. In support of this contention, the Proceedings of the National Academy of Sciences of the United States of America (PNAS) article titled “The influence of large-scale wind power on global climate,” states, “Wind power is a renewable resource, but the rate of its renewal is finite and, in some respects, comparatively small.” In my opinion, if the rate of renewal is finite and small, it should not be classified as a renewable resource at all.
Wind Is Not Limitless
Wind is in part created by solar energy. Winds are caused by the uneven heating of the atmosphere by the sun, the irregularities of the earth’s surface, and rotation of the earth. Wind flow patterns are modified by the earth’s terrain, bodies of water, and vegetative cover. Many of these factors are fairly constant entities, so any extraction of energy by wind turbines means there is less energy for other functions. Furthermore, the energy extracted by wind turbines cannot be replenished as suggested by the term renewable.
Think of it this way, if the wind initially had the equivalent of 1,000 MW of power and 100 MW were transformed by wind turbines, no mechanism or magical terrestrial phenomenon exists to replace the lost 100 MW, it’s removed from the atmosphere completely. Therefore, wind power is certainly not renewable in the context of its ability to be refurbished.
With worldwide air and water temperatures soaring, ocean currents diminishing, polar ice caps and glaciers melting, seas rising, storms intensifying, and floods and fires everywhere, humans must look at all possible contributing factors that may be causing these climatic changes, including wind power. Interestingly, the PNAS paper mentioned earlier does support a relationship between wind power and climate change. Its authors wrote, “We find that very large amounts of wind power can produce nonnegligible climatic change at continental scales.” Additionally, the article says, “Large-scale use of wind power can alter local and global climate by extracting kinetic energy and altering turbulent transport in the atmospheric boundary layer.” This clearly establishes the link to climate change.
Adverse Side Effects
Unfortunately, wind power has seldom been identified as a possible source of climate change, while still being portrayed as a green renewable inexhaustible source for worldwide generation of power. The only negatives many people recognize are turbine blade noise and vibration, visual impacts, migratory bird losses, economics, and the impact on civilian and military radar.
Onshore and offshore wind farms are expanding all over the world, while manufacturers continue to develop larger and larger turbines to help promote their industry. World wind generation capacity is doubling about every three years, and that is something to be very concerned about because of its impact on climate change.
Although local environmental and aesthetic impacts of wind power may have been explored, there have been few recent assessments and studies of climatic and other impacts from the increased use of wind turbines. More research, studies, and analyses are needed to evaluate the consequences on global climate of the decreased energy in the wind from the rise in wind turbine power generation. Some obvious topics for further evaluation include global warming with dangerously high temperatures, rising seas, torrential rainfalls, devastating hurricanes, deadly forest fires from exacerbated wind patterns, polar warming, diminished ocean currents, higher ocean temperatures, and a decrease in the earth’s rotational speed and shift of the earth’s axial tilt.
Learning from Past Mistakes
We must not forget the shortsighted thinking of the early to mid-1900s, when it was believed that the world’s lakes, rivers, and oceans had limitless capacity to absorb sewage, chemicals, pollutants, nuclear waste, and waste heat. It was also believed that the atmosphere was so vast that humans could freely release whatever gases, toxins, and pollutants without any discernible effects. As we know now, the earth is very fragile, and everything people do has some long-term effect. This same warped thinking cannot be repeated for wind power.
My hope is that this commentary will inspire engineers, physicists, and scientists to express their thoughts and urge further research into the climatic effects of wind power, especially because it appears to be one of the contributors that must be recognized and addressed in perspective.
In conclusion, wind power’s classification as renewable is a misnomer, both erroneous and misleading, and a dangerous precedent. Equally disturbing is the widespread and intentional disregard of the consequences of wind power on climate change. ■
—Farouk D. Baxter, PE ([email protected]) is a nuclear power plant consultant, specializing in electrical power systems..