Most UK power stations are currently burning plant matter, coal or biomass to minimize their carbon footprint. The carbon dioxide released on burning plants such as Miscanthus and poplar is assumingly absorbed during photosynthesis by the next batch of ‘energy crops’ planted in their place. Investigators from the University of Leeds suggest that roasting ‘green’ fuel prior to burning it into coal-fired power stations leads to more plant matter.
The fibrous plant matter is very difficult to process in the mills that are used to grind dry lumps of coal into dust before they are burned. During the roasting process called torrefaction, the plant matter gets heated to approximately 300 degrees centigrade in an air-free container. The bulky biomass transformed into a dry, energy-rich fuel is cheaper, easier to move around and comes along with a much longer shelf life. At the time of the research, experts utilized two common energy crops, willow and Miscanthus. Experiments initiated on these plants assert that when the plant matter is ‘torrefied’ it can be ground into a powder just like some good quality coals.
The research findings can supposedly benefit farmers interested in growing energy crops on areas of poorer quality soil. Professor Jenny Jones and colleagues are currently conducting tests to find out if the torrefaction process can be scaled up in designing ‘blueprint’ for industrial engineers. Also questions about the safety, practicality and environmental impact of large-scale torrefaction will be thoroughly analyzed.