The LCOE for coal runs from $0.01 to $0.12 with a median of $0.05/kWh

http://en.openei.org/apps/TCDB/

But that doesn’t tell the full story. First, wind has an operating cost of about a penny per kWh. And it gets a subsidy of 2.3 cents per kWh. That means that wind can sell for -1.3 cents and break even. It can make money simply giving its electricity away (2.3 – 1 = profit).

Coal and nuclear plants can’t shut down and turn back on quickly. When demand is low and the wind blowing they have to sell their product for next to nothing and sometimes less than nothing in order to make wind farms drop out. Even without the 2.3 cent subsidy they would be hurting just competing against wind able to sell for a bit over 1 cent.

If thermal plants sell close to zero a number of hours then they need to sell at higher prices other hours in order to stay in business.

Coal and nuclear depend on a relatively few hours of very profitable sales to keep their bottom line positive. I don’t know the number of hours in the US, but I recently read that coal plants in Australia make 25% of their annual profits during only 40 hours a year when demand is super high and the wholesale price of electricity it through the roof.

Now along comes solar. Solar is starting to produce electricity under 10 cents (without subsidies). The traditional earning hours for coal and nuclear are hot, sunny afternoons. Solar is starting to kill those profits. It’s happened in Germany. It’s starting to happen in Australia. Solar is lowering the wholesale price ceiling and wiping out the high revenues of peak demand hours. Plus end-user solar is lowering peak demand.

And then there’s natural gas, which is cheap right now. If the wholesale price of electricity goes above 5 cents or so, on come the gas plants. Away goes profits for coal and nuclear.

First week of May we saw a perfectly fine, paid off nuclear reactor close down because it was losing money. We saw another which had been down for repairs announce that it wouldn’t be coming back. About a quarter of our existing nuclear reactors are in danger of bankruptcy.

http://www.nytimes.com/2012/10/24/business/energy-environment/economics-forcing-some-nuclear-plants-into-retirement.html?_r=1

Australia is seeing coal plants closed due to lots of rooftop solar.

http://reneweconomy.com.au/2013/shift-from-base-load-slashes-value-of-state-coal-generators-92669

The utility business is getting a major shake up. Interesting times ahead.

Still, the average price comparison metric can provide a sense of how close wind might be to displacing existing fossil fuel plants.

It makes no sense to compare a new wind turbine, solar panel, nuclear plant LCOE against, for example, the price of electricity coming from a TVA dam built in the 1930s.

An old, paid off nuclear plant can produce electricity for five or six cents. In the best of cases a bit lower. A new plant that has to pay for its capital expenses and financing would produce electricity above 12 cents per kWh.