So if somebody wants to build a coal-powered plant, they can; it's just that it
will bankrupt them because they're going to be charged a huge sum for all
that greenhouse gas that's being emitted
West Virginia (along with, more important in electoral terms, Ohio, Pennsylvania and Montana, among others) depends on the coal industry. 40,000 jobs in the state are directly in the industry. So even at a hospital in a non-coal region of the state, people are pissed.
So I've spent most of the past 6 hours or so trying to talk NICU nurses out of burning Obama in effigy. It's important, like with many political "gaffes", to look at the complete context of the quote. It's long, so I'll just post a link.
In short, Obama is talking about charging electric companies for the damage to the environment that pollution from their plants does. A traditional coal plant that pumps tons and tons of CO2 into the air would contribute to global warming. Obama wants to use a cap and trade system, under which companies are taxed based on how polluting their plants are, to encourage cleaner techniques, such as trapping CO2 instead of emitting it. So what he meant in the bad-sounding quote was if someone wanted to build a traditional, high-polluting coal plant, they can; it's just that it would bankrupt them..."
Obama is not suggesting ending the use of coal for electricity; he's just saying that consumers and producers should pay its true cost, instead of just releasing pollution for all of us to deal with.