Wind Power Extraction: Limits and Impacts

Thursday - November 2 2023, 00:58 UTC - 1 year ago

Wind power is growing source of renewable energy and has the potential to affect the climate on a global-scale. We use a three-step approach to estimate how much power can be extracted and its potential impacts. The first method outlines the processes associated with wind power generation, followed by a momentum balance model and then general circulation model simulations. The maximum estimates in the range of 18-68 TW are significantly lower than recent estimates that claim abundant wind power availability.

Basic circulation model indicates that increasing global wind power by 18-34 times from 1 Terawatt today will be like doubling atmospheric CO2. This would be counter to the stated goals of reducing CO2 from energy using solar and wind. There is a trillion tons of excess CO2 in the atmosphere since the industrial age started. Each part per million of atmospheric CO2 is 7.82 gigatonnes of CO2. The current CO2 readin g is 417. There are 3.2 trillion tons of CO2 in the atmosphere. Doubling atmospheric CO2 would be 6.4 trillion tons of CO2.

Thanks to reader, Brett Bellmore, for reminding me about this research paper.

Wind power is a rapidly growing source of renewable energy and is projected to become an increasingly important energy provider in the near future. Wind power extraction has the potential to affect the climate on a global-scale due to the coupling of the atmosphere to the extracted energy flux. To effectively identify how much wind power can be extracted and the potential impacts of this extraction, we need a better understanding of the limits of wind power extraction on a global-scale. We use a three-step approach to estimate this limit.

First, they outline the processes associated with wind power generation and extraction with a simple power transfer hierarchy based on the assumption that available wind power will not geographically vary with increased extraction for an estimate of 68 TW. Second, we set up a simple momentum balance model to estimate maximum extractability which we then apply to reanalysis climate data, yielding an estimate of 21 TW. Third, we perform general circulation model simulations in which we extract different amounts of momentum from the atmospheric boundary layer to obtain a maximum estimate of how much power can be extracted, yielding 18–34 TW. These three methods consistently yield maximum estimates in the range of 18–68 TW and are notably less than recent estimates that claim abundant wind power availability. Furthermore, we show with the general circulation model simulations that some climatic effects at maximum wind power extraction are similar in magnitude to those associated with a doubling of atmospheric CO2. They try to understand fundamental limits to renewable energy resources, as well as the impacts of their utilization, it is imperative to use a "top-down" thermodynamic Earth system perspective, rather than the more common "bottom-up" engineering approach.