Cost and expense all depend on how far-reaching your thought process goes. If you look too short term, the switch to alternative sources is, indeed, too costly. If you look too far ahead, you see that eventually the sun will flare and we'll be left sitting on a burned out pile of rock anyway, so why bother?

The solution (to prolong the interim) lies in following a balanced approach to changing our energy use patterns. We need to ween ourselves off fossil fuels and decrease our energy reliance. We need to develop alternative sources of energy, to augment the existing sources that feed the grid. Exploiting the oil reserves accessible through protected lands extends our use of natural gas and oil for only a few years; it just puts off the inevitable.

We need to change our way of thinking. Eventually we need to find a way off this glorious rock, or we will be as extinct as the fossils that we're using as fuel today.

And on that cheery note, I bid you "Adieu' for now.
Bart