David LaGesse, May 16, 2013 (National Geographic)
“…[S]ome scientists are…arguing that the laws of physics will limit wind's potential for meeting the world's energy needs. The controversy arises from the turbines themselves…[R]esearchers have explored the issue of turbines stealing energy from the wind, creating drag or a ‘wind shadow’ of air slowed by the spinning blades. Each turbine added to a particular landscape captures less energy…[At a point, more turbines may produce] no more energy… “…[But the potential of wind] is far above the levels we are seeing harvested in even the most aggressive wind-energy countries today…Many proponents of replacing fossil fuels count on wind power as the single biggest source of renewable energy for the nation's future. Industry experts, for example, have predicted wind could supply a third of the world's electricity by 2050…[and it would take billions of turbines worldwide] for wind energy to become oversaturated to the point that it undermines its own effectiveness…”
click to enlarge“…[The Jacobson and Archer] study projected that producing half the world's energy needs in 2030, or six terawatts of energy, would take some four million 5-megawatt (MW) turbines…Jacobson contends that even that large number of turbines could be spaced in such a way to keep them from robbing each other of efficiency…Even eight megasize wind farms, each with a half-million turbines, would prove efficient enough to output a total of four terawatts, or about a third of the world's projected energy needs in 2030, according to his paper…[Four million turbines] spread among thousands of wind farms…would boost the turbines' efficiency enough…[to] provide at least half the world's energy needs, Jacobson said… “Geography and politics will combine to limit turbine placement to certain areas, and the question of diminishing returns from dense arrays will become a significant factor [other researchers say]…No doubt, the models will be refined as research continues [they argue]…”
0 comments:
Post a Comment