The future's green
Scientists set sights on biomass to reduce fossil fuel dependence
Switching from non-renewable carbon sources to renewable bioresources may be the key to combating our dependence on fossil fuels, according to Dr Charlotte Williams, from Imperial's Department of Chemistry, and colleagues from the Georgia Institute of Technology and the Oak Ridge National Laboratory.
In an article published recently in Science, the researchers have considered the viability of a future based on biomass. Their paper outlines the scientific challenges of designing a facility that will process all components of this biomass, making a range of products that give maximum value with minimum waste.
Biomass consists of plant material, vegetation or agricultural waste that can be used as a renewable fuel or energy source. Products of biomass include biofuels and biomaterials, both of which are derived from plants which take carbon dioxide from the atmosphere as they grow. Currently the level of global biomass production is somewhat conservative. To overcome this, the fundamental constraints on the productivity of energy crops need to be identified. Some of the measures that have been taken to address these constraints include modifying photosynthesis in order to increase light capture, as well as inserting genetically engineered versions of plant defence genes into the crop plants.
The scientists believe that, along with cultivating successful energy crops, efficient refining of biomass is also essential for developing sustainable biofuels and biomaterials. Dr Williams said: "We're looking at a future for biomass where we use the entire plant and produce a range of different materials from it. Biomass has a completely different molecular structure compared with hydrocarbons from oil. That means we'll need to develop new techniques so that we can transform plant material into everything from high value products such as perfumes and plastics to higher volume products such as fuels."
The refining of biomass requires a biorefinery, a facility that integrates biomass conversion processes and equipment to make useful products from biomass. According to the National Renewable Energy Laboratory, the biorefinery concept is similar to today's petroleum refineries, and industrial biorefineries are the most promising route to the creation of a biobased industry.
Dr Williams and her colleagues seem to agree. They have a vision for a 21st century biorefinery that will contribute to sustainability not only through its sole dependence on renewable bioresources, but also by recycling waste, which will result in the whole process becoming carbon neutral.
In an attempt to realise this vision, Imperial have teamed up with Georgia Tech and Oak Ridge to set up a strategic alliance, known as the AtlantIC Alliance, in order to assess the scientific and technological potential of a "bio-based future" from a range of perspectives.
With regards to biomass production in the UK, around 25,000 tonnes of biofuel are being produced each year, but half of this is imported. Additionally, there is no bioethanol produced as a road fuel. The EU Directive 2003/30/EU has set the target of 5.75% biofuels usage by the end of 2010.
Additionally, the UK Government has responded to this initiative by examining the feasibility of introducing a Road Transport Fuel Obligation (RTFO) as a means of boosting the take up of bio-fuels.
