Cheap, sustainable energy could be growing all round us
Bioenergy is a form of energy that could bring many benefits to the developing as well as the developed world. “The biomass used to create bioneregy or biofuels is abundant in many developing countries, especially in the form of agricultural by-products such as rice husk and sugar cane bagasse," Dr Jenny Jones of the University of Leeds tells us. As an energy source biomass is nearly 'CO2 neutral', that is (assuming it is grown in a sustainable way) any bioenergy crop will fix as much CO2 from the atmosphere as it grows as will be released when it is burnt. Growing bioenergy crops can give a boost to rural economies, providing an alternative market for existing crops. Biomass also has the advantage that it can be mixed in with other fuel sources: "Co-firing biomass with coal is currently undertaken at several UK power stations, and this can reduce CO2 emissions while taking advantage of the efficiencies associated with large scale boilers," Dr Jones explains.
To get the maximum benefit from bioenergy technologies the biomass concerned has to be burnt in an efficient manner. Here a computer model shows the flow of particles at different temperatures during wood combustion in a pulverised fuel furnace
There are still plenty of challenges for bioenergy researchers to tackle. Scientists and engineers are investigating how to breed the most desirable traits into promising energy crop candidates and then farm, harvest and use the biomass efficiently and economically. “Other issues include corrosion, fouling and slagging in boilers,” comments Dr Jones, “this is a particular problem associated with agricultural residues from wheat and straw where the potassium and chlorine content can be high.” Integrating biomass processing with other technologies such as gas turbines, engines and fuel cells is also important. EPSRC supports a diverse portfolio of bioenergy research including work at Leeds and the SUPERGEN – Biomass, Biofuels and Energy Crops Consortium of which Dr Jones is a member. EPSRC and the DTI also support the Bioenergy Network of Excellence which links together eight leading European bioenergy institutes. According to Dr Jones the future could be bright if research can drive innovation in the emerging bionergy industry: “the impact could be very large, with new biomass-based industry replacing elements of the petrochemical industry as oil reserves decline.