The Energy Saving Trust’s Basic Guide to Biofuels

As Biofuels are becoming increasingly important, with the Government is introducing legislation requiring all fuels to contain a proportion of biofuel by 2008, The Energy Saving Trust has issued a basic guide to help understand the issues surrounding biofuels.

What are biofuels?
Biofuels are fuels derived from biomass – plant material extracted from crops such as oil seed rape, and waste oils such as used cooking oils. The two most important biofuels in relation to transport are biodiesel and bioethanol.

Compared with conventional fossil fuels, biofuels usually lead to savings in carbon dioxide (CO2) emissions. The amount of CO2 released through the burning of biofuels is the same as that taken out of the atmosphere a year or two earlier when the biofuel crops were grown. However, biofuels are not “carbon neutral” and the actual CO2 benefit varies widely. This variance depends on the carbon emissions associated with its cultivation (including fertiliser use), harvesting, processing and transportation to the point of use.

The production of biofuels relies on intensive farming to produce the required biomass. There is some concern over the impact on agriculture and food production, as well as environmental damage caused from this farming. It is of particular concern in countries such as Indonesia, where the growth in export markets for fuel crops such as palm oil has led to the removal of forests. In the UK the Government attaches great importance to ensuring that biofuels come from sustainable sources, and is planning to introduce an environmental reporting scheme as an integral part of the Renewable Transport Fuel Obligation (RTFO), which is due to come into effect in April 2008.

Bioethanol is a petrol substitute produced by fermenting plant material such as sugar cane, sugar beet or wheat. Bioethanol fuel is widely used in some countries such as Brazil and more recently in Sweden, but in the UK refuelling infrastructure is limited.

There are currently fourteen WM Morrisons sites in selected areas of England (concentrated around East Anglia and Somerset) where bioethanol is available. Vehicles that can run on bioethanol are known as flexi-fuel vehicles (FFVs), as they can run on 100 per cent petrol or any blend up to 15 per cent petrol/85 per cent ethanol. Ford and Saab supply FFVs to the UK market.

More information about bioethanol and about the UK demonstration projects can be found at

Biodiesel is more widely available in the UK than bioethanol. Almost all biodiesel in the UK is produced from oil seed rape primarily because this crop is well suited to the UK climate. However, biodiesel may also be produced from other crops including sunflowers, soya and rapeseed.

To produce a fuel with similar properties to conventional diesel, plant oils are reacted with methanol to produce methyl esters.

Biodiesel mechanical and warranty issues
All vehicle manufacturers accept blends of up to five per cent biodiesel (95 per cent fossil diesel) in their vehicles. Provided the fuel used meets European standard (EN590), fuel suppliers do not have to declare bio content up to five per cent, so some fleets may be using five per cent biodiesel without knowing it.

Most manufacturers state that blends of more than five per cent biodiesel should be avoided and that vehicle warranties will be invalidated if higher blends are used. In some instances fleet managers have negotiated directly with manufacturers for vehicle warranties to be maintained with higher blends. A small number of vehicle manufactures have approved a blend of up to 30 per cent biodiesel, these include Peugeot and Citroën.

Biodiesel suppliers
For a list of suppliers of biofuels and other alternative fuels click here:

Fleet applications
As noted above, many fleets may already be using low percentage biofuels without knowing it, and in a few years all vehicles will be using low blend biofuels. This is because the Government is due to introduce the Renewable Transport Fuel Obligation (RTFO) in April 2008, which will require 5 per cent of all UK fuel sold on UK forecourts to come from a renewable source by 2010.

If you require more information on the RTFO visit:

Fleets can look at moving to higher blend biofuels, which represents an opportunity to move away from fossil fuels. However, the availability of refuelling stations selling high blend biofuels is limited. Some large fleets may be able to overcome this by bunkering biofules on site. In using these fuels, fleets should ensure that using high blend biofuels will not invalidate their warranties.

Biofuels development
The biofuels currently available are the first generation of biofuels. There is considerable development towards the next generation with new processes for producing biofuel. In addition to biodiesel and bioethanol, biogas is an emerging fuel with many production, efficiency and emission benefits.