Transport currently accounts for ¼ of the UK’s carbon emissions, 85% of which comes from road transport.

Liquid biofuels were originally used by the first cars. For example the Ford Model T, produced from 1903 to 1926 was designed to run completely on ethanol and the first diesel engine ran off peanut oil. However when crude oil became more cheaply available, cars began using fuels derived from mineral oil.

What are biofuels?

The two main types of biofuel are biodiesel and bioethanol.

Biodiesel is produced from oily crops such as rapeseed, sunflower, palm etc, or from recovered used cooking oil. These oils are less viscous then fossil diesel so require processing to make them flow easier in fuel pumps. Biodiesel can be used as an additive with fossil diesel (up to 5%); high quality biodiesel can be used in any diesel engine car without damaging it. In the future it is hoped to be used in higher blends and even neat, this would however require changes to the engine components.

Bioethanol is used as an additive (up to 5%) in petrol. It too can be used in higher blends but vehicles require engine modifications (which are relatively cheap). For example the majority of cars in Brazil run on at least 30% blends. Car manufacturers including Ford are currently producing “flex-fuel” vehicles which can run on anything up to 85% bioethanol. Bioethanol is alcohol derived and can be produced from almost any organic substance e.g. grass and wood, but the technologies for doing so are not available on a commercial scale. At present bioethanol is produced from starchy crops like wheat, sugarbeet and sugar cane (as seen in the picture). Bioethanol is not produced in the UK as yet, however large volumes are being produced in the US and Brazil with around 3% of all US gasoline sales in 2005 being from bioethanol.

Other types of biofuel include biogas, which can be used in compressed natural gas (CNG) powered cars (of which there are only about 500 in the UK). Biogas is produced by collecting methane which is naturally emitted at landfill sites and areas of rotting vegetation. Research is currently looking into using green algae, grown in large fresh-water tanks for biofuel. Initial studies suggest that the energy produced this way is much greater then any land-based biofuel crops and there could be considerable fossil fuel savings whilst using a limited area of land.

Current biofuel use and targets

Between 2000 and 2005 biodiesel output quadrupled and ethanol production doubled, with Brazil producing the greatest amount of ethanol at 16 billion litres per year from its sugar cane industry. At present, 60% of cars can now run on a fuel mix made up of 85% ethanol.

Biodiesel is currently available as a per cent blend at about 100 filing stations in the UK.

Bioethanol is starting to be used in UK petrol. In March 2006 some 8 million litres (approximately 0.4% of UK petrol sales) of bioethanol were sold.

The EU target of 5.75% of transport fuel to be from biological sources by 2010 is unlikely to be met.

The Renewable Transport Fuels Obligation (RTFO) in the UK aims to have 5% of fuel sold at the pump as biofuel by 2010. The RTFO will be put in place in March 2008 and will require suppliers of fossil fuels to ensure a proportion of the fuel they supply in UK comprises green fuels. Certificates can be claimed when biofuels are supplied, if suppliers do not have enough certificates at the end of the obligation period they will be fined 15 pence per litre.

Carbon savings from Biofuels

In principle biofuels can help to reduce carbon emissions compared with fossil fuel. When the fuels are burnt they release no more carbon then was taken in during the growth of the plant so are deemed carbon neutral. However there is some argument over the carbon produced during the growth, transporting and processing of the crop.

Greenergy Fuels Ltd, a British company, who supply biofuels retailed through supermarket forecourts, supplied 17.1 million litres of bioethanol and biodiesel, which it calculated a saving of more than 40,000 tons of carbon dioxide emissions during the first quarter of 2006. The firm compared this savings to taking more than 50,000 average family cars for three months.

A recent UK government publication declared that boifuels reduced emissions "by 50-50% compared to fossil fuels".

A large scale study in the US recently found that switchgrass derived ethanol fuel cut CO2 emissions by 94% compared to an equivalent volume of petrol. The study is looking at growing switchgrass on marginal land, so that it would not be in competition with food crops.

What are the costs involved?

Environmental

The growing demand for biofuels will mean putting millions of hectares of land under intensive agriculture which will have major impacts on habitats, biodiversity, water supplies, and soils. Land is a limited resource and bioenergy crops take up a large amount of land. If half of the crops needed to meet the UK’s 5% renewable transport target (by 2010) were grown in the UK, 740,000 hectares of land would be needed, and imports are therefore likely to play a big role in helping the UK meet it's target.

In tropical countries millions of hectares are being converted to bio-crop monocultures to fuel cars in the US and Europe. The biofuel industry is growing in the tropics as crops grown in the tropical climate yield about five times as much energy as those grown in temperate zones. For example Corn produces 145 kg of oil per hectare per year, where as the tropical jatropha produces 1590kg of oil per hectare per year.

There could be catastrophic effects from replacing tropical rainforests (major carbon sinks) with biofuel crops. Deforestation rates in the Amazon had been coming down for eight years until 2003 when they suddenly increased, almost solely due to soya monocultures. A soya-based biodiesel programme, supported by President Lula’s government, is almost certain to accelerate the destruction of the Amazon forest. Vast tracts of Amazon forest are being set ablaze to clear the land for soya, destroying the valuable habitat and releasing stored carbon.

Palm oil has by far the highest energy yield of all the biodiesel crops grown at present (5000kg of oil per hectare per year). This, together with low wages and the lack of any rights for plantation workers, gives south-east Asian palm oil a great competitive advantage in the new free biofuel market. Biodiesel companies in the UK, favour palm oil as their main source, meaning that once the UK’s Renewable Transport Obligation comes into force, in March 2008, the amount of biodiesel sold in the UK will dramatically increase and it is likely that most of it will come from Indonesian and Malaysian palm oil. However, this sector is linked to massive forest and peat fires, which, in 1997, released the equivalent of 13-40% of all global emissions from burning fossil fuels. In that year alone, 5 million hectares of forest were burnt.

Picture: Palm Oil Plantations, Central Kalimantan, Borneo. Indonesia’s rainforests are currently being cleared at a rate of 300 football fields per hour (UN Report, 2—7)

On a more positive environmental note, one advantage of many biofuels over most other fuel types is that they are biodegradable and so relatively harmless to the environment if spilled.

Economic

Biodiesel is usually two to three times more expensive to produce than fossil diesel but this varies widely (current high oil prices mean wholesale (ie pre-tax) diesel is now approaching 30p per litre, biodiesel around 45p per litre). The exception is biodiesel from recovered cooking oil, which is cheap, but often of a low quality, which could cause damage to some car engines.

Bioethanol is more expensive to produce than petrol, especially from crops like wheat, but countries such as Brazil can produce it efficiently from sugar cane (prices as low as 7p per litre before import tariffs, which are currently around 20p per litre). The rising demand for biofuels will lead many farmers worldwide to grow crops for biofuel production rather than for food production. This could lead to reduced food production, increased food prices and inflation. The impacts of this would be greatest on poorer countries or countries that rely on imported food for their subsistence.

Looking to the future

The points below have been taken from the Department for Transport website (Jan 2008).

• from April 2008 there will be a requirement to report on the carbon savings and sustainability of biofuels;
• from April 2010 the Government aims to reward biofuels under the RTFO according to the amount of carbon they save. This will be subject to compatibility with EU and WTO requirements and future consultation on the environmental and economic impacts;
• from April 2011 the Government aims to reward biofuels under the RTFO only if they meet appropriate sustainability standards. This will be subject to the same provisos as above and providing the relevant international standards are in place to allow this;
• the Government will ask the RTFO Administrator to report every three months on the effectiveness of the RTFO's environmental reporting system, and on the carbon and sustainability effects of the RTFO;
• the Government intends to set challenging targets for: the level of greenhouse gas savings we expect to see from biofuels used to meet the RTFO, the proportion of biofuels from feedstock grown to recognised sustainability standards and the amount of information we expect to be included in sustainability reports;
• the Government has asked the Low Carbon Vehicle Partnership to explore the feasibility of a voluntary labelling scheme, allowing responsible retailers to show that the biofuels they supply are genuinely sustainable. Any scheme would need to be compatible with WTO rules.