Wind turbines and coal power

Ok, so, how many wind turbines would it take to replace a coal power plant? Well, I underestimated...but I also think Rod overestimated.

Here's a more accurate calculation.

First of all, how much energy does a coal power plant produce? Well, in the US there are 1,493 coal generators with total nameplate capacity of 335,830MW or 225MW/coal power plant (http://www.eia.doe.gov/cneaf/electricity/epa/epat2p2.html).

When talking about energy produced from wind power, we also have to factor in that the wind isn't always consistent, and on the low side, wind turbines will have a 20% capacity factor. So, a 3MW turbine would probably have an effective rating of 3*0.2=0.6MW, or as high as 1.2MW with a 40% capacity factor.

So, you would need 375 wind turbines (each rated to a max. power of 3MW) with a 20% capacity factor to replace a 225MW coal power plant or 187 wind turbines with a 40% capacity factor.

Now, most new coal power plants are probably going to have a nameplate capacity of 500MW (maybe even higher), not 225MW. So, in this case, we would need 833 wind turbines (3MW turbines at 20% capacity factor) to replace that 500MW coal power plant. BUT, wind turbines can also go up to 5MW now. So, if your wind farm had 5MW turbines, then you could replace a 500MW coal power plant with 500, 5MW turbines (with 20% capacity factor) or 250 5MW turbines with a 40% capacity factor.