Problems with biofuels in recreational vesselsProblems with biofuels in recreational vessels

by Anton le Rutte*
  Not long ago, the Federal Government brought into law new fuel standards regulating the production, distribution and sale of biofuels. These standards were not designed to mandate the sale of biofuel but to ensure that, wherever it is available, it conforms to specific standards and is appropriately labelled.
  The NSW Government, on the other hand, has legislation in place that mandates the use of biofuels – administered through a special department styled the Office of Biofuels. Other states, so far at least, appear to be taking a more measured approach.
  Arguments supporting the production and blending of ethanol and biodiesel with petrol and diesel respectively are well understood. And subject to the purpose for which such blended fuels are used, these arguments have merit.
  But a number of characteristics, specific to each of these fuels, make them unsuitable for fuelling vessels used for recreational purposes. The most significant of these and common to both fuels concerns shelf life – the time it takes for the fuel in the tank of a vessel to deteriorate to the point where it is likely to compromise the safe running of an engine.
  As it concerns ethanol blended petrol, moisture in the air of a tank is absorbed by the mixed fuel until a point is reached where the water absorbed into the mixture, along with the ethanol, separate from the petrol and sink to the bottom of the tank. This is known as phase separation.
  Depending on where the pick up point is in the tank, the engine is now treated to either water soaked ethanol, which stops the engine dead, or octane depleted petrol, which can cause pre-ignition (pinging), loss of power and probably engine damage.
  The time it takes for this to occur can be as little as two weeks and it is for this reason that ethanol blended petrol is acknowledged by even the authorities to be unsuitable for recreation vessels.
  The NSW Government, to its credit, has dealt with this in two ways – firstly, it has provided for a specific exemption from its new biofuels legislation the mandatory ethanol content of regular unleaded petrol (ULP) for the fuelling of boats and, secondly, NSW Maritime has broadcast a warning to all boat owners of the dangers of using ethanol blended petrol. BIA Victoria has also warned Victorian boat owners not to use ethanol fuels in their boats to avoid potentially costly damage to engines and fuel systems.
  The problem with biodiesel is the time it takes to deteriorate. Much of its promotion is based on its successful use in industry – construction, transport and even inshore marine (ferries, tourist boats and tugs etc). But common to its success in these applications is the short time in which the fuel is in the tank.
  Biodiesel has a shelf life of somewhere between three and six months – not a problem in an industrial application, where tanks are cycled in days if not hours, but a big problem for recreational vessels where the fuel cycles are very much longer.
  Biodiesel blends, even at the 5% level, exhibit poor long term storage characteristics. Biodiesel in storage over periods longer than three to six months typically begins to exhibit heightened acid content (which attacks fuel injection systems and the engines lubricating oils), higher viscosity, and the formation of gums and sediments that clog filters.
  This deterioration moreover is not linear – once it starts, the rate of deterioration increases exponentially. And if there is any of this contaminated fuel still left when it is decided to top up, the rate at which the new fuel deteriorates will be considerably accelerated.
  It should also be noted that a lot of the data used to support the Australian biodiesel industry comes out of Europe and the US where the feedstock is rapeseed and canola respectively. Not only does this process actually absorb carbon but also the resultant product is understood to be more predictable.
  In Australia, most of the feedstock for the production of biodiesel is recycled cooking oil, which is understood to be considerably less predictable as to quality and considerably less stable over time. The reason recycled cooking oil is used in Australia is because it is about one third of the price.
  Unfortunately, Federal fuel labelling law makes it unnecessary to label biodiesel blends up to five percent – the Federal Government’s view being that there is no difference between straight diesel and a 5%-biodiesel blend. But this view, particularly as it concerns its use in applications involving long term storage, does not accord with the views of the oil companies or independent fuel analysts.
  The use of such fuel in recreational vessels is considered unwise and could clearly compromise safety at sea.
  Interestingly, the IMO, a United Nations specialist agency responsible for improving maritime safety, seems to agree. Through its adoption of ISO 8217, covering the specification of marine fuels, biodiesel is effectively excluded from being used to fuel ships for international voyages.
  The NSW Government, meanwhile, has mandated a 2% volumetric biodiesel content referable to the aggregate of all diesel sold in this state by (it is expected) the end of this year – increasing to 5% by January 2012. And because NSW has taken the same very selective view in regard to biodiesel as its Federal counterparts, no specific exemption for the fuelling of boats has been provided for. Fortunately, the mandate is volumetric which means that diesel sold with a higher than 2% or 5% biodiesel blend can offset diesel sold with a zero blend.
The Boat Owners Association of NSW has taken the view that the use of all biofuels should be avoided. It strongly recommends to boat owners that they take the following action.
  1. Insist that your yacht club or marina operator only sells ethanol free petrol. NSW biofuels legislation provides for a specific exemption for such outlets to sell regular unleaded petrol (ULP) not containing ethanol.
  2. If purchasing petrol from a petrol station, purchase a higher grade fuel not containing ethanol. It may be more expensive but it might save you motor. And remember that any petrol containing ethanol has to be so labelled under Federal law.
  3. Insist that your yacht club or marina operator only sells straight diesel (not containing biodiesel). It can stipulate this arrangement with major oil suppliers by contract – specifying to the supplier exactly what it is contracting to purchase. Yacht clubs and marina operator would do well to take this issue seriously and to advise their members and/or clients accordingly.

*Anton le Rutte is a member of the Boat Owners Association of NSW.