Red Diesel to be ‘virtually sulphur free’

Boaters advised to check the grade of fuel they are buying following changes to fuel quality due to come in January 2011. 

An amendment to the fuel quality Directive means that, from 1 January 2011, all gas oil, commonly known as 'red diesel' in the UK, must not contain more than 10 milligrams of sulphur per kilogram of fuel, but what does this mean for recreational boaters.

The amendment, adopted by the European Parliament and EU Council in April 2009 covers fuel marketed for use in 'Non-Road Mobile Machinery', which includes recreational craft when not at sea and inland waterways vessels. The 10 milligrams per kilogram limit means the fuel will be virtually sulphur free.

Sulphur free gas oil is needed to ensure the reliable operation of pollutant emissions control systems, which will be fitted to new off-road equipment from 2011 to meet EU emissions requirements. However, the rules for the sulphur content of gas oil used in sea-going vessels will not change for the time being.

Two diesel grades

Currently, UK fuel supply includes two diesel grades, road diesel and gas oil. Road diesel is already virtually sulphur free and may contain up to 7% by volume of biodiesel whereas gas oil generally contains no biodiesel but up to 1,000 milligrams of sulphur per kilogram.

The permissible sulphur content of gas oil for non-seagoing vessels is now the same as road diesel. Duty rates applicable to gas oil are, however, not affected by the introduction of sulphur free gas oil.

The oil industry originally indicated that because of limitations in the production and supply infrastructure, they expected to meet the requirement for non-seagoing gas oil largely by supplying road diesel with a red marker dye added, rather than by producing a third grade of diesel (i.e. biodiesel-free sulphur-free gas oil).

Following pressure from the RYA and the marine industry, the oil producers have now suggested that they might now produce such a third grade of diesel.  However, it remains uncler how widely available this fuel will be.

Fuel may contain some biodiesel

It is therefore evident that fuel supplied to the inland waterways and many recreational craft may contain a proportion of biodiesel.

It is important therefore that boaters ask suppliers what grade of fuel it is that they are buying as fuel containing biodiesel requires different storage and usage requirements.

Guidelines on usage of fuel containing biodiesel

  • Remove all water from the tanks and conduct monthly checks that they remain free of water
  • Tanks that don't already have drain points for removing water are likely to need modification
  • Examine sight gauges on older fuel storage tanks for signs of leakage and replace any leaking seals
  • If you are having tanks serviced before you receive the new fuel it would be advisable to replace fuel seals as a one-off, precautionary exercise
  • Replace fuel filters after two to three deliveries/turnover of the new fuel
  • Ensure the content of tanks is turned over every six months or in any event no less often than every 12 months to help prevent blockage of filters.

Most engines are fully compatible with fuel containing biodiesel. However, some fuel system components on older engines, in particular fuel seals and pipes, may not be compatible with sulphur free gas oil.

Users of older equipment should examine fuel systems in the months following the switchover and replace seals or pipes with compatible ones if there are signs of leakage.

Further advice on the storage and usage of gas oil containing biodiesel.

Stuart Carruthers, RYA Cruising Manager