When I recently made some observations on the progress of the Pickens Plan for American energy security, I downplayed the momentum behind T. Boone's ideas surrounding natural gas as a transportation fuel. It looks like I spoke too soon.

The very same afternoon, a trio of Senators (including Majority Leader Harry Reid) introduced the NAT GAS Act in Congress. This legislation, which Reid may be able to stick into the forthcoming Senate climate bill, would provide a host of tax breaks for natural gas vehicles (NGVs). Basically, most everything for which Chesapeake Energy (NYSE:CHK) began campaigning last year.

The U.S. market for NGVs is currently tiny, with Honda Motor's (NYSE:HMC) Civic GX currently representing the sole passenger vehicle option, despite NGVs being rolled out by American carmaker General Motors in foreign markets like India and Thailand, for example.

Being a Civic owner myself, I was curious to check out the specs. What first jumped out at me is that the GX has a higher sticker price and poorer highway fuel economy than the Civic Hybrid Sedan. The car does shine in the realm of fuel cost, however, which keeps the payback period quite short. Unlike some of the ridiculous luxury hybrids out there, this does in fact look like a reasonable consumer option.

A bigger sticking point, I think, is the lack of fueling stations. Besides Pickens' own Clean Energy Fuels (NASDAQ:CLNE), there isn't much of a concerted effort to roll out compressed natural gas pumps around the nation. Of course, the NAT GAS Act (a cute acronym for New Alternative Transportation to Give Americans Solutions) covers refueling stations as well as the manufacture and purchase of NGVs. So, it's at least possible for the legislation to move us beyond the current chicken-and-egg impasse.

Given the recent success of ExxonMobil (NYSE:XOM), Southwestern Energy (NYSE:SWN), and the rest of the energy industry in unlocking massive natural gas deposits, I can certainly see the appeal of phasing in natural gas in place of gasoline derived from crude oil. On the question of whether natural gas trumps electricity or green gasoline, however, I'm far less convinced.

So, what's your favored future fuel, Fool? Please leave a comment below.