The Democratic leaders also pledged a 25 percent reduction in oil use by 2020, largely by developing fuel alternatives in the United States.

And there is simply no other fuel alternative for the faster-than-light stardrive.

Both Ildirans and human scientists had reworked the stardrive, but there simply was no fuel alternative.

Here, we look at some weirder fuel alternatives used by companies.

Offshore drilling should be part of a much larger policy, including fuel alternatives, to achieve energy independence.

You've driven to work the day after Thanksgiving, using your own turkey grease as a fuel alternative!

Public transportation also provides an arena to test environmentally friendly fuel alternatives, such as hydrogen-powered vehicles.

The hydrogen based fuel alternative boasts 12-percent greater fuel efficiency when compared to either of the remaining fueling options.

Nuclear fission produces roughly a million times more energy per unit weight than fossil fuel alternatives [source: Helman].

Both problems require fossil fuel alternatives - not just environmentalists' favorite hobbyhorses, like wind and solar power, but biofuels that can take the place of gasoline.