The Economics of Green Jobs

Here's a question: We keep getting told how many jobs are going to be created through green technology, and how wonderful it will be for the US economically. But all of those jobs are going to get factored into our overall energy costs, right? So, if lots more people are going to be employed making green energy than all those nasty fossil fuel producers (who will surely lose their jobs, due to the fact that they are fundamentally evil), doesn't that mean that the cost of energy has to go way, way up? And if energy costs go way up, doesn't that imply that US GDP goes down, or at least flattens out a lot? And doesn't that really mean that cutting over to green energy is more-or-less a zero-sum game?