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Submission + - Renewable Energy Might Not Be 2

lee1 writes: "Physicist Axel Kleidon of the Max Planck Institute for Biogeochemistry
in Jena, Germany has shown that it is a mistake to consider the wind and
waves to be truly renewable energy sources. Build enough wind farms to
replace fossil fuels, he says, and we would reduce the energy available
in the atmosphere and actually accelerate climate change. We know from
thermodynamics that only a modest fraction of the solar energy reaching
Earth is available as 'free energy' we can use, taking the form of
winds, ocean currents, and lifting of evaporated water. The rest becomes
heat, which is not available to do work. By building wind and wave farms, we
will be converting part of the sun's useful energy into thermal energy.
The effects of this would probably show up first in the wind farms
themselves, where the gains expected will be less than predicted as the
energy of the Earth system is depleted. Kleidon’s calculations show
that the amount of energy which we can harness from the wind is reduced
by a factor of 100 if you take this into account. In addition, sucking that much energy out of the
atmosphere will alter precipitation, turbulence and the amount of solar
radiation reaching the Earth's surface. The effect
will be comparable to the results of doubling
atmospheric concentrations of carbon dioxide. Even current photovoltaic
designs will contribute to global warming, because they
convert only a small fraction of the light that hits them converting the rest to heat that warms the environment."

Going the speed of light is bad for your age.