GRANGEMOUTH oil refinery is to reduce the amount of biodiesel added to its conventional fuel while the investigation into problems with farm machinery continues.

Following emergency talks with the National Farmers Union Scotland, Grangemouth's operating company, Petroineos, has apparently accepted at least the possibility that the percentage of recycled biological oils being added to standard diesel might be involved in the current epidemic of blocked filters on tractors.

Fatty Acid Methyl Ester extracted from biological sources like cooking oil and tallow has been allowed in non-road diesel (so-called red diesel) since 2006, under the Renewable Fuel Transport Obligation, but was rarely used as such, due to its relatively high price.

However, changes to the RTFO in 2018 brought more binding biofuel targets into force, compelling all suppliers of fuel into the UK market to be using at least 12.4% biofuel by 2032 - and the progression towards that target saw the red diesel minimum percentage lifted to 9.75 % from January 1, 2019.

As such, this autumn was the first when all of Scotland's tractors headed out to harvest with at least a tenth of their tanks filled with FAME, and when fuel filters started blocking up with gunk, farmers were not slow to make the connection. Unlike diesel cracked from crude oil, FAME is a 'hygroscopic' substance, which means that it attracts and retains water, and can therefore have issues with algal growth in storage.

All that would have been on the table when NFU Scotland met with Petroineos on November 20, and the company has now 'acted swiftly' to test the hypothesis by giving farmers reduced FAME in their fuel, not a moment too soon given that cold weather is a trigger for fuel problems, and temperatures have plummeted this weekend.

Since its meeting with Petroineos, NFUS has continued to log calls from members, and now has 380 individuals who have reported fuel issues. As well as its dealings with Grangemouth, the union has mounted a 'determined and concentrated' political lobbying effort, contacting the Cabinet Secretary for Transport, Michael Matheson MSP, corresponding with the Department of Transport, Transport Scotland and the Scottish Government, and calling for a short term derogation on biofuel percentages - and a longer term taskforce to look into its future use.

President Andrew McCornick said: “It is positive to see Petroineos acting swiftly off the back of the discussions with NFU Scotland and other industry leaders. This issue is not a quick fix though and may not completely resolve this problem. We need government to work with producers and users to find a workable, long term solution to these issues.

“We need to see an expert working group established and NFU Scotland needs to be involved to represent our members, whose businesses have been heavily affected by these biofuel issues," said Mr McCornick.

“I would like to personally thank each and every member who has taken the time to report this issue to NFUS," he added "It is important that other members who have yet to report problems contact NFU Scotland and report it. This information is still important and will help to give us the best possible understanding of problem so that we can feed these into discussions going forward.”