Abstract
This article deals with the discussion about the real and effective use of biomass mainly for energy supply, since the fuel production from crops and other biomass resources has attracted much attention in the world. Several concrete examples of the evaluation of biomass utilization were exhibited in terms of two different standpoints; one was “qualitative” evaluation which includes the ratio of input/output energy, a new index of CO2 emission reduction, the comparison of the electricity generation density using solar energy, and the energy efficiency of the cars with different source of power. The other was “quantitative” evaluation which means the amount and distribution of really utilizable biomass resources and a comparison of the amount with their demands. And then, an assessment on the validity of “Jatropha” production was presented on the basis of the result obtained from a field survey by the author mainly in Indonesia. As a conclusion, it was emphasized that biomass should be used as a local energy source, not as an alternative to petroleum, and in addition, a concrete plan for increasing the production of domestic forest biomass was proposed.
