Vessel biofuels

This page outlines what biofuels are, the implications for petrol and diesel engine owners if they use biofuels, and where to access further information.

What is happening?

In the interests of promoting the use of cleaner, greener, locally made fuels in NSW, the State Government has taken steps to ensure the broader use of biofuels.

Biofuels are perfectly safe to use in road vehicles designed to be compatible with them, but they create some significant issues for boat owners.

The biofuels available in NSW are ethanol and biodiesel which are mixed in varying degrees with petroleum. For example E10 is petrol containing 10 per cent ethanol, B20 is diesel containing 20 per cent biodiesel.

E10 is now widely available in NSW and, subject to certain exemptions including for marinas, the minimum ethanol content of all regular unleaded petrol sold in NSW after July 2011 will be 10 per cent. Petrol that contains ethanol must be labelled at the dispenser. Premium grade unleaded petrol without ethanol will still be available.

On 1 March 2009, the national Diesel Fuel Quality Standard was amended to permit up to 5 per cent biodiesel in all diesel fuel in Australia.  B20 will also be increasingly available but any diesel blend with more than 5 per cent biodiesel will have to be labelled at the dispenser.

Marine engine manufacturers are producing new engines capable of using biofuels, however there are still some significant safety and fuel management issues of which boat owners need to be aware.

Implications for petrol engine owners:

Generally ethanol blended fuel is not recommended in a marine application because ethanol absorbs water readily, to the point where it may seperate from the petrol.

The ethanol itself may cause problems for carburettors, fibreglass fuel tanks, rubber fuel lines, fittings, seals and filtration systems, particularly in older engines, and non-standard engine installations.

The NSW Government has provided for exemptions so that regular unleaded petrol may continue to be available from marinas after 2011.

Boat owners who purchase their petrol from service stations will be able to purchase premium grade unleaded fuel without ethanol.

E10 should not be used in a boat unless:

  • The engine manufacturer recommends the engine model is compatible with E10
  • The fuel tank, fuel hoses/fittings and fuel filtration system use ethanol-compatible components
  • The vessel is used frequently, ensuring fuel is not stored for long periods of time
  • The fuel system, including fuel tank, is regularly inspected and serviced to remove water and debris
  • Specific procedures are adopted for “off season” fuel management
  • The vessel will not be operated in conditions where engine failure may result in a serious threat to the safety of the vessel and its occupants.

Always consult your marine dealer or engine manufacturer before using E10.

Implications for diesel engine owners

If you intend to use biodiesel fuel in your vessel:

  • Ensure the engine manufacturer recommends that the engine model is compatible with biodiesel before any biodiesel blend greater than 5 per cent is used
  • Ensure the fuel tank, fuel hoses/fittings and fuel filtration system use biodiesel-compatible components
  • Biodiesel has a shorter storage life than mineral diesel.  Oxidation stabilisers are added by biodiesel manufacturers to meet the Fuel Quality Standard, however an additional fuel stabiliser additive may be required if biodiesel blends are stored for more than a few months.  Acidity should be measured monthly
  • Biodiesel blends are more susceptible to microbial contamination.  Sound fuel management practices, including monitoring and especially keeping all water out of the fuel system, are essential
  • The fuel system, including fuel pumps, tanks, filters and injectors should be regularly inspected and serviced to remove water and debris
  • Specific procedures should be adopted for ’off season’ fuel management.

More information on biofuels

For more information on this issue, see:

Explanatory brochures and other specific information may also be available from your engine manufacturer.

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