BIODIESEL What you need to know, and what’s changed

Sales Executive at IPU Group

Biodiesel is not new. Rudolf Diesel, the inventor of the diesel engine, tested peanut oil fuels in his engines. Vegetable oils were also widely used during the Second World War as a diesel substitute. Biodiesel is now a common ingredient of modern diesel blends, and organisations have to educate themselves on how to store and maintain it.

Although many types of biodiesels are available, Fatty Acid Methyl Ester (FAME) is the most common. It is used to form most diesel blends used across the world today. FAME is used because it contains less sulphur than petrochemical diesel. Lower levels of sulphur reduce the health risks associated with diesel and reduce the number of unburned hydrocarbons, carbon monoxide (CO) and particulate matter in the atmosphere.

When compared to most pure petrochemical diesel, biodiesel reduces: ● CO emissions by up to 50%. ● Particulate emissions by 30%. ● Exhaust emissions of total hydrocarbons (a contributing factor in the localised formation of smog and ozone damage) up to 93%. ● The levels of polycyclic aromatic hydrocarbons (PAH) (which are identified as potential cancer-causing compounds) by 75-85%.

Despite the benefits, most engines will not function reliably on pure biodiesel. It’s necessary to use it in conjunction with petrochemical diesel. The current ratio used across Europe is 7% biodiesel to 93% petrochemical diesel, identified as B7. The ‘B Factor’ identifies the percentage of biodiesel used, e.g. B100 is pure 100% biodiesel and B20 is 20% biodiesel and 80% petrochemical diesel.

‘We’ve never had to maintain our fuel before, why now?’ Technically speaking, even petrochemical diesel required maintenance, but introducing biodiesel blends has accelerated the rate of degradation. Biodiesel suffers from more aggressive water and microbial contamination than petrochemical diesel.

The natural ingredients facilitate bacterial growth. Biodiesel is hydroscopic, meaning it attracts water, and whilst a contaminant in its own right, it encourages the growth of microbial organisms known as ‘diesel bug’.

As the ratio of biodiesel in fuel rises, so will the instances of fuel contamination. The level of FAME currently sits at 7% in the UK, but it is expected to rise to 20% in the future future. It is already 8% in France. Preventative measures must be taken by anyone who stores diesel.

A fuel management programme, like IPU’s, is essential to keep biodiesel in a good condition. Regularly sampling and testing fuel gives you a clear view of what’s happening in your fuel tank. Fuel cleaning removes contamination and restores fuel back to original condition. Fuel polishing units act as a preventative measure, to reduce circulate fuel and reduce contamination build up. Adding fuel additives to the tank help to reduce contamination. On-engine filters are the last line of defence to protect your engines from dirty fuel blocking filters and damaging injectors.

There are now two grades of petrol available on the forecourt: E5, 97+ octane and E10, 95 octane. The new E10 aims to reduce CO2 emissions.

The ‘E’ number represents the percentage of bioethanol the fuel contains. And, as a result, some vehicles could suffer. There is a strong risk of ‘corrosion’ in some components such as hoses and seals. The lower octane is also less efficient and likely to impact fuel economy and miles per gallon. Check the government website to ascertain your vehicle’s compatibility.