|MadSci Network: Environment & Ecology|
This is a good question! Actually, the energy generated in the Sun that we see now was already created millions of years ago as the Sun fused the nuclei of light atoms into heavier ones. That energy took millions of years to reach the surface as heat, and then the light and heat radiated from the sun actually takes a little over 8 minutes to reach us. The energy being produced by the Sun now will emerge the same way in millions of years whether we use the energy that's currently hitting us or not. If we convert some of the sunlight incident on the Earth into electrical power instead of it being lost as heat, it will eventually become heat again as that electrical power is used. So the answer is no, we have no effect on the sun. Not to worry, even if solar power did have an effect on the Sun (which it can't) the amount of sunlight that hits the earth is approximately approximately one part in 2 billion of its output. (I calculated this from the apparent area of the Earth when looking at the sun, compared to the area of the whole sky at the Earth's distance.) The same can be said of hydroelectric power since it's a form of solar power! The energy to heat water and make clouds (hence rain) comes from the Sun. That lifts the water up, and it rains down. We use a few hundred feet of gravity pulling a tiny fraction of this water downward again to generate power, but we use only an incredibly small fraction of the rain that falls on the Earth for power. This process of creating clouds uses far more solar energy than human solar farms could ever achieve. I recall reading that a single thundercloud contains enough water to fill enormous railroad tank cars in a train over 20 miles long...just one cloud, and that's about a mile up in the sky! Imagine how much power is released when the clouds around the globe make rain, it's a truly mind-boggling amount of energy from solar power released every day, it dwarfs all our tiny man-made methods of energy production. And it's a form of solar power. If you become a scientist someday, figure out how to use a large natural power source like that and you'll solve a lot of the world's problems (and probably become exceedingly wealthy).
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