CO 2-balance for the cultivation and combustion of Miscanthus

Abstract

Miscanthus ‘Giganteus’ is a perennial C 4-grass from East Asia. The biomass yield-potential of Miscanthus has been investigated in Germany since 1987. The combustion of biomass offers a possibility for lowering emissions of the greenhouse gas CO 2. The CO 2 which is set free during combustion has previously been fixed by the plants. The study analyses the demand for energy and the CO 2-emissions which are involved in the production of Miscanthus, beginning with propagating the plants to transporting the biomass to the power station. Energy demand and CO 2-emissions are compared with those of the provision and combustion of hard coal. The energy content of Miscanthus biomass harvested from one hectare, about 20 t of dry matter, corresponds to the energy content of 12 t hard coal. For each gigajoule of hard coal, 96.6 kg CO 2 are emitted during provision and combustion. By combusting Miscanthus instead of hard coal 90% of CO 2-emissions can be saved.