ABSTRACT
The term biomass is defined as “different materials of biological origin that can be used as a primary source of energy.”1,2 Merriam-Webster OnLine Dictionary38 defines biomass as “plant materials and animal waste used especially as a source of fuel.” An attractive aspect of biomass utilization is its renewability, which ultimately guarantees that the source will not be depleted. With plant and plant-derived materials, all energy is originally captured by photosynthesis. Going by these definitions of biomass, it can be safely said that energy from biomass has been exploited by humans for a very long time. The burning, or incineration, of biological substances such as wooden materials has long been used to provide warmth. It has been estimated that, in the late 1700s, approximately two thirds of the volume of wood removed from the American forest was for energy generation.3 Because wood was one of the few renewable energy sources readily exploitable at the time, its use continued to grow. During the 1800s, single households consumed 70 to 145 m3 of wood annually for heating and cooking.4,5 A small percentage of the rural communities in the U.S. still use biomass for these purposes. Other countries such as Finland use the direct combustion of wood for a percentage of their total energy use.6 Finland and the U.S. are not the only countries that use biomass consumption to supplement their total energy usage. In fact, the share of biomass energy in the total energy consumption of a country is far greater in African nations and many other developing countries. Table 12.1 shows the percentages of biomass consumption by several
“developed” countries.7 The data shown include all biomass consumption for energy generation, which includes, for example, corn for ethanol as well as wood for combustion.
