Would gas to liquid (GTL) fuel work better than diesel fuel? PBO's engine whisperer, Stu Davies ponders the question

Recently I fell foul of the dreaded diesel bug when a plug of gunk in the fuel line caused our engine to fail at just the wrong moment.

We were returning to Conwy after a trip to Ireland and the engine failure necessitated returning to the Menai Strait under sail, and then a night on a mooring in Beaumaris during storm Betty.

An internet search for non-FAME diesel later revealed the existence of something called ‘GTL fuel’ as a straight replacement for diesel, something I’d not heard of but seems to have many advantages over biodiesel.

I wonder if you know whether recreational boat users could obtain gas to liquid (GTL) fuel?

Apparently, offshore vessels, inland barges, tourist boats and cruise ships in Europe are already using Shell GTL fuel which is said to offer:

  • 6-13% NOx reduction
  • 15-60% particulate matter reduction
  • Reported noise reduction of approximately 8dB

Claimed five-year storage life and zero biofuel content may considerably help with the dreaded bug.

I’ve been unable to find any details on costs or suppliers, it seems users may require a commercial account.

Mike Spencer-Harty

Stu Davies replies:

There are a couple of issues here: diesel bug and how to address it, and pollution and how to address it.

Shell produces GTL in the UK, a synthetic diesel fuel that is refined at a molecular level from gas rather than crude oil.

The product burns cleaner and produces less NO2 and that appears to be its raison d’etre.

Certas Energy is agent for the fuel but, as you mention, it’s currently aimed at supplying businesses like heavy haulage, agriculture, commercial marine and construction industries with their own fuel bunkers – it’s not available on garage forecourts.

Continues below…

However, to buy GTL to address diesel bug is to buy a product that is not aimed at that market.

I’ve been advising for the last year or so, with the introduction of FAME to our diesel, that your fuel system including the tank and the liquid that you put in it is a maintenance item now.

Basically, you’ll need to add biocide, clean your tank physically every couple of years, change your filters regularly and check your fuel lines for blockages.

Having said all that, an easier option to obtain a higher spec diesel with just a small amount of FAME in it is to use Shell V Power diesel (or a competitor equivalent).

A contact I know personally, who has recently retired from Shell, assures me that GTL diesel is used in the blending of V Power.

For a deeper analysis of diesel bug and modern fuels see ‘How should I look after my diesel fuel’.


Enjoyed reading Is there a better diesel fuel?

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