Royal Society: Biofuel Area Requires Detailed Assessments, More Research and Coherent Policy to Realize Potential Sustainability Benefits
|Thermal, biological and chemical pathways for biofuel and chemical production. Click to enlarge.|
A report from a working group of experts convened by the UK’s Royal Society has concluded that although biofuels have a potentially useful role in tackling the issues of climate change and energy supply for transportation, important opportunities to reduce greenhouse gas emissions from biofuels, and to ensure wider environmental and social benefits, may be missed with existing policy frameworks and targets.
The group was convened to consider the science and technology prospects of delivering efficient biofuels for transport in the broader context of the environmental protection and sustainability. The report, Sustainable Biofuels: prospects and challenges, comes at a time when the EU’s transport biofuels targets (5% of transport fuel supply from biofuels by 2010 and 10% by 2020) are coming under increasing criticism.
Although biofuels offer a number of perceived benefits—carbon-neutrality, support for emerging bio-economies, and petroleum replacement—the full picture is much more complex as different biofuels have widely differing environmental, social and economic impacts, according to the report.
The authors outlined four major caveats for biofuel use:
“Biofuel” is much too broad a term—it covers a wide variety of products with many different characteristics and a wide range of potential savings in terms of greenhouse gas emissions.
The wide diversity and complexity of options for producing biofuels in itself presents a challenge to fully understanding the relative benefits that different biofuels can offer. It is therefore not possible to make simple generalizations about biofuels being ‘good’ or ‘bad’. Each biofuel option needs to be assessed individually, on its own merits.
Each assessment must address the environmental and economic aspects of the complete cycle—growth of the plant, transport to the refinery, the refining process itself (including potential by-products such as specialty chemicals), wastes produced, distribution of the resultant fuel to consumers, end use, and potential for pollution. Such assessments would help to determine the extent to which different biofuels are carbon neutral.
Widespread deployment of biofuels will have major implications for land use, with associated environmental, social and economic impacts that must in turn be assessed. Here, in particular, unintended consequences may reduce or override the expected benefits.
The assessments must address the global and regional impacts, not just local ones.
The authors conclude that for biofuels to deliver a realistic substitute for conventional fuels and meet sustainability criteria there must be substantial improvements in efficiency throughout the supply chain linking feedstocks to their final uses.
This will require a major research and development effort in both public and private sectors, according to the report. Key objectives should include:
Increased yield per hectare of feedstock while reducing negative environmental impacts;
Development of new feedstocks that can, for example, be grown in more hostile environments, be more readily processed and be capable of generating a variety of products;
Improved methods of processing, in particular for lignocellulose feedstocks;
New physicochemical systems for biofuel synthesis;
Development and demonstration of integrated biorefineries;
Integration of the supply chain to gain the maximum efficiencies;
Integration of biofuel development with engine development;
Internationally agreed methods of assessing sustainability.
However biofuels have a limited ability to replace fossil fuels and should not be regarded as a ‘silver bullet’ to deal with transport emissions. Progress towards a sustainable solution for transport and the demand for mobility requires an integrated approach, which combines biofuels with other developments, including vehicle and engine design, the development of hybrid and fuel cell vehicles and supporting infrastructure, public transport, better urban and rural planning to address the increasing demand for transport as well as more specific policies to reduce demand and encourage behavioural change.
A coherent policy approach to biofuels—currently lacking—is required, the authors argue, to avoid the unintended consequence of solving one problem at the expense of exacerbating another.