13 September 2012
WIND AND SOLAR
This just in ~ new research indicates that "there is enough energy for people to reap from the wind to meet all the world's power demands without radically altering the planet's climate, according to two independent teams of scientists. Wind power is often touted as environmentally friendly, generating no pollutants. It is an increasingly popular source of renewable energy, with the United States aiming to produce 20 percent of its electricity by wind power by 2030. Still, there have been questions as to how much energy wind power can supply the world, and how green it actually is, given how it pulls energy from the atmosphere.
"Adding wind turbines (see image above, click to enlarge) of any kind slows winds, and .... adding more than a certain number of turbines would no longer generate more electricity. Still, simulations suggest that at least 400 terawatts ~ or 400 trillion watts of power ~ could be generated from surface winds, and more than 1,800 terawatts could be extracted from winds throughout the atmosphere. In comparison, people globally currently use about 18 terawatts of power.
"Simulating a century's worth of amped-up wind energy production suggests that harvesting maximum power from these winds would have dramatic long-term effects on the climate, triggering major shifts in atmospheric circulation .... In contrast, extracting enough wind energy to satisfy current global power demands would only have minimal climate effects, as long as wind turbines were spread out. Doing so might affect surface temperatures by about 0.1 degree Celsius and affect average precipitation by about 1 percent.
"The researchers suggest half these turbines be placed in the ocean, while the others would require a little more than 0.5 percent of the Earth's land surface ~ about half the area of Alaska. Virtually none of this area would need to be used solely for wind, but could for instance also serve as farmland, ranchland or wildlife preserves. Spreading out the ground-based turbines in windy locations worldwide such as the American plains and the Sahara would increase efficiency by keeping them from stealing energy from each other, and would reduce their overall environmental impact."
To my knowledge these are the first studies to quantify the available power available from surface winds, as well as from winds at various altitudes, and compare that to the current and projected power needs of the human population. The studies also take into account possible adverse effects from erecting too many wind turbines, ranging from climate effects to mortality inflicted on migrating birds. It appears quite impressive that wind power alone could meet the energy needs of the planet.
Geopolitical realities may complicate matters, however. Implicit among the assumptions of the studies is the notion that a global power grid would operate in tandem with global wind energy production. Currently power grids are at best national or regional (as in the European Union). Given the positive impact on any nation's economy, the potential for eradication of poverty, and the potential stabilizing effect on political relations, one would hope that the majority of nations would be willing to participate ~ mediated, perhaps, by an international body such as the United Nations.
Together with ongoing developments in solar power (see image below), this writer believes that it is time to rid ourselves of reliance on more dangerous and costly energy sources such as nuclear power, not to mention time to reverse corporate and government determination to eke out the last ounce of profit from highly polluting, non-renewable energy sources such as fracking for natural gas, offshore drilling for oil, or mining for coal. The ideas and the funding have been available for decades. All that's been missing is the vision and the will. The time has come to embrace the vision, and to exert our will ~ in the voting booth, in the media, and on the streets.