Originally Posted by corrado33

Let's do some math. In the US in 2014 we used roughly 40 quadrillion BTU of energy to produce electricity. That's about 12 trillion kWh. If a wind farm can produce 3 W/m^2 (the max of UK wind farms, where it's MUCH more windy), it'd take roughly 62 MILLION square miles of wind farms to power the US. Oh, the US is only 3.8 million square miles large. (That includes Alaska...) Oh, and I also assumed that the wind farms are producing their 3 W/m^2 all 24 hours in a day.

Ok, fine, wind isn't that great of a power source. What about solar? Solar farms can produce a bit less than 200 W/m^2 (I'm being generous). Even at that energy density, it'd take ~ 1.9 MILLION square miles of solar panels to power the US. So, you know, a bit less than 2/3rds of the US. Again, I assumed that the solar panels were producing max power for 12 hours every day. I'm not even going to talk about cloudy days, or how the majority of the US isn't suited for solar panels, or how we can't store energy well so if we had a solar panel based power generation system we'd have no electricity at night, or how electricity transmission is very lossy, especially since we'd have to convert the DC into AC to transmit it (DC has historically been difficult to transmit over long distances due to the difficulty of converting it to higher voltage. Transformers make this easy.) so that's even more lossy. Etc. etc. etc. Please note that I've only talking about ELECTRICITY here. While the production of electricity does take a lot of energy, it's not the only thing that NEEDS energy in the US. The US, in total, used about 85 quadrillion BTU of energy. Now, you can discount the losses associated with the production of electricity if you want for these calculations, but you'd still have to produce electricity for everything else in the US that doesn't currently use it. Cars, jets, etc.