This topic came up the other day, I’m not sure exactly how or why. The question proposed: What was the most prominent source of electrical power generation in the United States? Someone said nuclear power and I disagreed. I couldn't name the biggest source (I know Dad, I should know this) but I knew it was some sort of fuel that burned to turn a turbine.
I thought because coal was so bad for the environment that it would not account for 50% of generation. Surprise surprise. A diagram of electrical generation output:

Is that diagram about right? What do you see as being the biggest source in the decades to come?