Heard about the Haynesville Shale?

It's a newly discovered patch of Louisiana loam that could harbor 200 trillion - with a "t" - cubic feet of natural gas, reports the Wall Street Journal.

That coupled with other recent finds boost expert estimates of home-grown natural gas energy supplies equal to a century of demand.

You have to be a real sleuth - and persistent reader - to get to the kicker near the end of the long story. "Gas is now cheaper than coal in many parts of the country, leading utilites to burn more gas." The next sentence recounts the fact, known to many industry watchers, that of the 372 power plants planned in the next three years, 206 will burn coal and a mere 31 will combust coal.

Economics can be slippery. And what is cheap today may not be tomorrow. That goes for fuels. Natural gas is abundant and cheap today as a result of a two-year drilling spurt that boost production 11 percent. In that time, you no doubt recall, we had astronomical rises in fossil fuel prices. That was an incentive to hunt for oil and gas.

The timing of all this will have consequences, as Congress takes up proposals to put a price on greenhouse gas emissions as a means of throttling them back down.

Translation. Coal prices may be headed north - well north of the melting ice caps, while a supply glut will moderate natural gas prices as far as the eye can see.

We are the Saudi Arabia of coal, it has long been noted. We also have a kingdom of natural gas. Natural gas emits half the CO2 of coal, while coal currently is used to  produce more than twice as much electricity as natural gas. Regardless of where you stand on global warming, economics - at least for today - is swinging the needle away from coal and toward natural gas.