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- Biofuels Definition
- Common forms of Biofuel
- Benefits of use
- UK Government position
- Issues
Biofuels Definition
Biofuels are derived from biomass. They differ from fossil fuels in that they are derived from renewable sources, including crops, animal waste and some forms of ‘rubbish’.
Common forms of Biofuel
Bioethanol is the biofuel substitute for petrol (gasoline). It derives from cereal based crops – mainly wheat in the UK, sugar beet and maize (corn), soyabeans and sugarcane in the US and South America.
Biodiesel is the biofuel substitute for diesel. It derives from oilseed based crops – mainly oilseed rape (OSR) in the UK, and palmoil in South East Asia.
The two forms above are ‘first generation biofuels’, i.e. they are derived from raw materials that can be used in food production.
Biogas is the biofuel substitute for natural gas. It derives from organic waste materials including animal waste and waste generated from municipal, commercial and industrial sources through the process of anaerobic digestion. In the UK biogas can be generated through animal waste, it is also collected from emissions produced at waste landfill sites.
Benefits of use
The main practical benefit of using biofuel alternatives is, that within some volume constraints, they can be integrated with fossil fuels and used within existing energy systems such as car and lorry engines.
There are two main environmental benefits of using biofuels in place of fossil fuels. First, because they are renewable, biofuels offer the potential for long-term, relatively cheap, secure energy supplies. Second, biofuels can contribute significantly less to greenhouse gas emissions in their production and use than oil or natural gas.
So-called second generation biofuels, or synthetic fuels, although biomass derived, mimic the chemical characteristic of fossil fuels. This allows more comprehensive integration into the fuel supply stream. They can also be made from a higher proportion of "woody" biomass, straw for example as opposed to the corn itself.
UK Government position
The European Commission originally set a minimum target of 10% of vehicle fuel coming from alternative sources by 2020. There is also an interim target of 5.75% by 2010. The UK government announced that it would introduce a Renewable Transport Fuel Obligation (RTFO) as a way of supporting the use of bio-fuels and other renewable fuels in the transport sector and to meet the European requirement.
In November 2007 the Renewable Fuels Agency was established to manage the introduction of the RTFO, Chaired by Ed Gallagher, former Chief Executive of the UK environment Agency.
Concerns over the sustainability of biofuels during 2008 led to the Gallagher review, this looked at the indirect impact of biofuels on food production, biodiversity, food prices and land-take. The review proposed the rate increase of the UK's biofuel targets should be reduced to 0.5% per annum. Targets beyond 5% should only be implemented beyond 2013/14, three years later then originally proposed. Further, higher targets should include a specific obligation on companies to use advanced technologies, supporting second generation biofuels.
Issues
There are a number of environmental and social issues around the production of biofuels, two of which are summarised below.
‘Good’ versus ‘Bad’ biofuels
It is becoming clear that the source of a biofuel is a key determinant of its net sustainability benefit.
The best performing biofuels can deliver ten times more energy (output) than energy required to produce them and when used, a quarter of the greenhouse gas emissions compared to their fossil fuel equivalent. Ethanol produced from sugar cane in Brazil is often given as an example of a ‘good’ biofuel.
In contrast, the worst performing biofuels deliver significantly less energy, and contribute to greenhouse gas emissions. The increased emissions tend to be indirect of use, for example, through forest fires and clearing to make way for plantations. Biodiesel produced from palm oil in Indonesia is often cited as and example of ‘bad’ biofuel.
The Gallagher review reinforced the need for the development of sustainable biofuels and standards by which to assess individual fuels sustainability credentials.
Food versus fuel
The feedstocks of many first generation biofuels can also be used in food production. Indeed, many of the cereals and oilseeds are fundamental components of a wide variety of foodstuffs. It is often cited that the grain required to produce a petrol tank full of ethanol for a large car would be sufficient to feed one person per year.
There is the inevitable tension therefore that whilst using them for biofuels may have environmental benefits, there are social and economic consequences. In the short term the main consequence is likely to be higher demand for crops grown to produce biofuels; this may contribute to food price increases.
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