We still have used fuel sitting all over the place.

More modern technology would use less fuel to do the same work.

This was done so that the plane would use less fuel.

They used fossil fuels and even had their own dark age of a sort.

Boeing also plans to use alternative fuel on the 747.

Many countries are using more diesel fuel for a variety of reasons.

What did was the absurdity of using as much fuel.

By 2007, the plan calls for all vehicles to use such alternative fuels.

The other was for a two or three stage rocket using solid fuel.

Using less fuel will lead to more money in your pocket and a cleaner environment.