Iran's most important energy fuel is NOT oil today but it is its natural gas.

There is still enough astronic energy fuel on the planet to cause a huge explosion.

Thermal power plants convert energy rich fuel into electricity and heat.

Guanidine nitrate is a high energy fuel used in some gas generator and solid rocket propellant applications.

Oil was the most popular energy fuel.

Zip fuel designates a series of experimental boron-containing "high energy fuels" intended for long range aircraft.

Where particularly high energy fuels are a necessity - for example in aircraft - the only practical fuel is kerosene (natural or synthetic).

They also have the capacity to handle large volumes of renewable energy fuels, such as wood chips and biomass.

Bossart used this opportunity to advance work with high energy cryogenic fuels that resulted in the Centaur upper stage.

By and large, we have to import the other energy fuels.