Qun Tian, Gang Huang, Kaiming Hu, Dev Niyogi. Observed and global climate model based changes in wind power potential over the Northern Hemisphere during 1979–2016. Energy, Volume 167, 15 January 2019, Pages 1224-1235.
Using an observed dataset, we study the changes of surface wind speeds from 1979 to 2016 over the Northern Hemisphere and their impacts on wind power potential. The results show that surface wind speeds were decreasing in the past four decades over most regions in the Northern Hemisphere, including North America, Europe and Asia. In conjunction with decreasing surface wind speeds, the wind power potential at the typical height of a commercial wind turbine was also declining over the past decades for most regions in the Northern Hemisphere. Approximately 30%, 50% and 80% of the stations lost over 30% of the wind power potential since 1979 in North America, Europe and Asia, respectively. In addition, the evaluation of climate models shows their relatively poor ability to simulate long-term temporal trends of surface winds, indicating the need for enhancing the process that can improve the reliability of climate models for wind energy assessments.
“At today’s costs, $1 million invested in a modern wind turbine will produce, over 30 years of operation, about 50 million kWh (kilowatt-hours). And $1 million spent on utility-grade solar panels will produce about 25 million kWh over 30 years. Meanwhile, $1 million spent on a shale rig will produce enough natural gas to generate 400 million kWh over the same 30 years” click here
Lee M Miller and David W Keith. Observation-based solar and wind power capacity factors and power densities. Environmental Research Letters 13 (2018) 104008.
Power density is the rate of energy generation per unit of land surface area occupied by an energy system. The power density of low-carbon energy sources will play an important role in mediating the environmental consequences of energy system decarbonization as the world transitions away from high power-density fossil fuels. All else equal, lower power densities mean larger land and environmental footprints. The power density of solar and wind power remain surprisingly uncertain: estimates of realizable generation rates per unit area for wind and solar power span 0.3–47 We m−2and 10–120 We m−2 respectively. We refine this range using US data from 1990–2016. We estimate wind power density from primary data, and solar power density from primary plant-level data and prior datasets on capacity density. The mean power density of 411 onshore wind power plants in 2016 was 0.50 We m−2. Wind plants with the largest areas have the lowest power densities. Wind power capacity factors are increasing, but that increase is associated with a decrease in capacity densities, so power densities are stable or declining. If wind power expands away from the best locations and the areas of wind power plants keep increasing, it seems likely that wind’s power density will decrease as total wind generation increases. The mean 2016 power density of 1150 solar power plants was 5.4 We m−2. Solar capacity factors and (likely) power densities are increasing with time driven, in part, by improved panel efficiencies. Wind power has a 10-fold lower power density than solar, but wind power installations directly occupy much less of the land within their boundaries. The environmental and social consequences of these divergent land occupancy patterns need further study.
“Wind turbines are the world’s new ‘apex predators’, wiping out buzzards, hawks and other carnivorous birds at the top of the food chain, say scientists. A study of wind farms in India found that predatory bird numbers drop by three quarters in areas around the turbines. This is having a ‘ripple effect’ across the food chain, with small mammals and reptiles adjusting their behaviour as their natural predators disappear from the skies.” click here
“Infrasound has a frequency under 20 Hz and thus is not audible to the human ear. However the low frequency sound is physically perceptible at high sound pressure and lead to health consequences, a German medical researcher said.
Wind turbines convert 40 percent of the wind’s energy into power and 60 percent into infrasound, thus making them a real potential threat to human health.” click here
“If the US were to install a lot of turbines, Wind power could warm the United States by 0.24 degrees Celsius instead of cooling it, because wind turbines “redistribute heat” in the atmosphere. They mix the surface layers. (0.24C would be equivalent to two decades of recent warming.) The largest effect is at night where wind plants can warm the local area by 1.5C.” click here
“Thousands of aging wind turbines will eventually need to be decommissioned, but the disposal of this “green” technology could prove to be a dirty job for environmental regulators.” click here