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Greenhouse gas emissions and environmental sustainability of international biofuels production and use. - GA01105


Review of published and ongoing work on the greenhouse gas emissions and environmental sustainability of international biofuels production and use.


Global demand for biofuels is increasing rapidly – liquid biofuels, such as ethanol and biodiesel, represent an opportunity to diversify and secure energy supplies, reduce greenhouse gas emissions from the transport sector to mitigate climate change, and contribute towards economic development and poverty reduction in developing countries.

In March 2007, the EU Spring Council agreed a conditional target of 10% for the share of biofuels in overall EU petrol and diesel consumption by 2020, subject to sustainability of production, commercial availability of second-generation biofuels, and appropriate amendment of the Fuel Quality Directive. This underpins the recent EU commitment to a 20% share of renewable energies in overall primary energy consumption by 2020. Sustainable biofuels are being promoted domestically as part of the UK’s climate change programme, and in 2008, a Renewable Transport Fuel Obligation (RTFO) will be introduced with the aim of reaching a level of 5% biofuels by 2010, when it will deliver estimated carbon savings of around a million tonnes per annum. This is likely to involve increased imports of biofuels from developing countries, mainly from tropical zones.

Competing demands on land for food crop production, biomass production for heat and power and non-energy uses (e.g. biomaterials and forest products), and biofuels feedstocks are increasing the pressure on natural resources. Notwithstanding the socioeconomic impacts, there is mounting concern that the speed at which the international biofuels industry is expanding is not being matched by an adequate understanding of associated impacts on the environment. Achieving real greenhouse gas mitigation from biofuels will depend upon the sustainability of their production and use. A recent report on Sustainable Bioenergy published by UN-Energy has highlighted the risks of unsustainable biofuel production which potentially negates the greenhouse gas benefits biofuels offer. For example, deforestation which may result (either directly or indirectly) from increased international demand for biofuels feedstocks poses a real threat to international efforts under the UNFCCC to reduce emissions from deforestation in developing countries. The UN report also highlights the risk of negative impacts on habitat, biodiversity, and water, air and soil quality.

The UK is concerned that the consequences of increasing demand for biofuels will be largely manifest in developing countries. The developed world therefore has a key role to play. For this reason, the UK and some other EU Member States are committed to promoting only biofuels which have been produced in a sustainable manner. Internationally agreed standards on the sustainability of biofuels do not currently exist, however there are a number of commodity standards in existence and under development that also relate to biofuel feedstocks. The European Commission is currently consulting on how sustainability should be incorporated into biofuels legislation that is due to be proposed later this year. In addition, the UK Department for Transport recently announced draft requirements and guidance for a carbon and sustainability reporting system under the RTFO, including a requirement for transport fuel suppliers to meet sustainability standards by 2011. The UK is keen to promote these approaches internationally, including through the UK-Brazil-Southern Africa Biofuels Taskforce and the Global Bioenergy Partnership (GBEP).

It is essential that international biofuels strategies are developed within a policy framework that reinforces rather than undermines environmental sustainability, particularly in developing countries. Emerging UK policy on international biofuels therefore requires a comprehensive and robust scientific underpinning. To this end, Defra is seeking to commission a review of current scientific evidence and ongoing work on the greenhouse gas emissions and environmental sustainability of biofuels production and consumption, with the aims of informing policy development, assessing the need to strengthen the evidence base and identifying Defra’s research priorities in this area.


To identify and review published and ongoing work on the greenhouse gas emissions and environmental sustainability of biofuels production and use.


1 a) Identify and review both global and regionally-specific studies on the following three broad areas:

i. International pressure areas with regards to the supply and demand of biofuels feedstocks, currently and over the next 20years. This should include predictions of future land use changes (e.g. deforestation) and changes in impacts due to the effects of climate change (e.g. increased pressure on reduced water resources);

ii. First and second-generation biofuels - first generation products include biodiesel and bioethanol, generated from crops such as cereals, oilseed rape and sugar cane using long-established technologies. Second generation biofuels technologies are able to use a wider variety of feedstocks, including cellulosic materials such as straw and ‘woody’ biomass, and potentially even selective fractions of municipal waste. Second generation fuels typically offer greater greenhouse gas savings than first generation fuels and a more efficient use of land (more fuel per hectare). However second generation fuels are currently pre-commercial and require very high capital investment compared to current first generation biofuel production plants;

iii. Small (local community level) and larger-scale applications.

b) The review should seek to identify and review work on the following current and future environmental impacts of biofuels:

i. full life-cycle greenhouse gas emissions impacts of both first and second generation biofuels as a function of feedstock, production/consumption technique and country;
ii. habitat and biodiversity;
iii. water quality (e.g. nutrient leaching/eutrophication) and quantity;
iv. soil quality (runoff and erosion, acidification);
v. effects on food crop production, either directly (e.g. displacement by feedstock production) or indirectly (e.g. inflated food crop prices).
vi. direct and indirect land use change, such as deforestation; and
vii. air quality (e.g. pesticides; particulates, oxides of nitrogen, and ozone precursors from use in the transport sector).

Where possible environmental impacts information should be presented in the context of impacts from alternative options for low carbon transport and for use of biomass.

2 Identify what an environmentally sustainable approach to the global production and consumption of biofuels might look like, e.g. which crops and management practices and which end-uses of the fuels can best minimise impacts and maximise benefits? This should be supported by a table outlining best practice according to regional circumstances.

3 Identify and list the key institutions, processes and fora in which research and policy development in the field of the greenhouse gas emissions and environmental sustainability of biofuels is being undertaken.

4 Recommend areas for further research based on an assessment of weaknesses or gaps in the evidence base.
Project Documents
• Abstract : Review of Work on the Environmental Sustainability of International Biofuels Production and Use   (6855k)
Time-Scale and Cost
From: 2007

To: 2008

Cost: £37,385
Contractor / Funded Organisations
AEA Technology
Science Policy              
Fields of Study
Climate Change Adaptation