Renewable Energy

The Ground (Geo-Thermal)

Plants (Bio-mass)

Rain Water (Hydro)

The Sun (Solar-Thermal Photovoltaic)

Tide and Waves

Wind

All of the above are currently being developed to some degree in a bid to reduce the reliance placed upon coal, gas and nuclear energy production methods.

Biofuel

Electric

Hydrogen

Are all  fairly new sources of fuel for vehicles and are all an alternative to diesel and petroleum, which have a higher carbon footprint.