National Parks (and the ADA) are some of the few great things that America has going for it and turning Yellowstone National Park into a power plant would not be one of them.
You are not even trying to understand. Aesthetics is not more important than existence. If Yellowstone is not mined, then when it blows, there will be no Americans left to appreciate it.
Secondly, the mining stations will be limited. Yellowstone is a vast land. There is expected to be no diminishing of the forest.