Evaluation of Plant Biomass Potential and Technologies of Biomass Preparation and Utilization for Energy Purposes in Lithuania

Plant biomass used for power purposes is the most important energy source. At present plant biomass used for power makes up approximately 94% of all the renewable energy used in Lithuania. The work aim is to determine the technical potential of plant biomass growing and usage for power purposes and to investigate the technologies for biomass use. Wood as a fuel is most widely used at present in Lithuania. Total energy value of Lithuania-produced wood fuel was 720 thousands toe. Wood fuel potential in the nearest decade will be 871 thousands toe. Straw is another source of biomass fuel. About 0.5 Mt (million tons), i.e. 12-15% of the total straw yield can be used as a fuel in Lithuania. Potential of straw as a fuel makes about 167 thousands toe. The resources of plant energy biomass may be supplied by specially grown plants: willows, perennial grasses, rapes, cereals, sugar beets. 22% of agricultural land can be attributed for this purpose. Biogas can be produced from plant biomass in anaerobic reactors. The total biogas potential from plant biomass in Lithuania would amount to 61 thousands toe. About 3 10 thousand ha can be used to grow plants for biofuel. The technologies of growing, harvesting and fuel production from traditional feed-type grasses, coarse-stemmed vegetative plants and willows were evaluated and rational technique was selected. After energetic evaluation of the technologies it was concluded that the total energy input of growing and harvesting of grasses and legumes was equal to 8.3 GJ ha(-1), topinambour stems - 14.4 GJ ha(-1), sunflower stems - 11.3 GJ ha(-1) and willow stems - 15.0 GJ ha(-1), respectively. Energy input calculations show, that the technology of fuel preparation from traditional grasses is more advantageous than the technologies of fuel preparation from coarse-stemmed vegetative plants and willows.