I often get asked the meaning of 'Alternative Fuel' and what is actually covered by the 'label' - so here is a guide to what is currently available, remembering that this sector is fast changing - daily in some cases!

Basically, the label "Alternative Fuels" covers fuel that is not made from petroleum.

ALCOHOL
Ethanol and Methanol are included under this heading.

COMPRESSED NATURAL GAS (CNG)
This is natural gas, stored under high pressure.

ELECTRICITY
Stored in batteries, which are recharged from a renewable source.

HYDROGEN
Hydrogen is one of two natural elements that combine to make water, so one would assume it would be readily available. But it's an energy carrier and it takes a great deal of energy (and cost at present) to extract it from water. It is useful as a compact energy source in fuel cells and batteries.

LIQUID(FIED) NATURAL GAS (LNG)
Natural gas, which is stored at very low temperature. This is a non-renewable source, so doesn't really solve the problem.

LIQUID(FIED) PETROLEUM GAS (LPG)
Hydrocarbon gases stored under a low pressure (cold), as called Propane. This is a non-renewable source, so doesn't really solve the problem.

COAL-BASED LIQUIDS
Petroleum and diesel that doesn't come from Petroleum, but as it comes from coal is not really a better solution.

BIODIESEL
Similar to diesel fuel, but is made from plant (often rapeseed) or animal fat. Can be mixed with regular diesel if a vehicle will not run on pure biodiesel. Can cause problems if a large amount of farmland is used for its production over food.

STRAIGHT VEGETABLE OIL (SVO)
Made from plants and can be mixed with regular diesel as above.

VEG OIL (Veggie OIL)
Often recycled vegetable fat (chip oil), which has been cleaned and had certain chemicals added. Sometimes it is blended with SVO. Can be mixed with regular as above.