Hydro power is what percentage?
On average, 37% of the electricity to recharge the plug ins is produced by burning coal.

Where I live, by paying extra, you can opt in to 100% wind power. You still get the same mixture of sources but it makes you "feel good" just like the other so called environmentally friendly "feel good" activities. Like Gasohol.

Will the world build 1,200 new coal plants?
Brad Plumer Washington Post

Climate scientists have sometimes warned that it could prove impossible to avoid high levels of global warming unless the world stops building new coal-fired plants. But that's not a simple proposition. Across the globe, there are at least 1,199 coal plants now on the drawing board, according to a new report from the World Resources Institute.

Many of these proposed new plants are in China and India, which account for 76 percent of proposed capacity. Turkey and Russia also have big plans. And a growing number of coal plants are being proposed for developing countries such as Cambodia, Guatemala and Uzbekistan, nations that are looking to cut-rate sources of energy to fuel economic growth.