On the drive up to Pittsbrugh from Washington DC two things stand out: the billboards for the coal industry and the giant windmills slowly turning along interstate 76.

The coal industry is spending a chunk of change to make the point that more than half the state's electricity comes from mines. People here have been digging out coal for more than a century. 250,000 thousand people still make a living off the industry.

But now there are windmills here too. A new carbon economy is rising up. Pennsylvania companies are rushing to take advantage of new opportunities in nuclear, wind and solar power.

Most surprising thing I learned: Pennsylvania is fortunate to sit two to three miles above geological formations that might just be perfect places to pump in greenhouse gas emissions. The idea is to pipe the gas deep underground where, over time, it may eventually turn back into rock.

Imagine that. Pennsylvania could make money off greenhouse gases coming and going -- digging it up and burying it.

Maybe that's why I didn't find voters in Pittsburgh were overly concerned about plans by presidential candidates to cap and trade carbon.