Biomass

Bioenergy is mankind's oldest source of energy. Humans have been using biomass as an energy source for many thousands of years. Wood, for instance, was the most important material for heating and cooking for a long time until it was superseded by coal, crude oil and natural gas. Biomass is the most important renewable energy source worldwide. Even today, on average, seven percent of Asia's primary energy consumption is supplied by firewood, ten percent in Latin America and an estimated 40 percent in Africa, which can, however, lead in part to disastrous consequences for the forests and soils of the countries affected. Although wood and charcoal are principally considered renewable energy sources, even extensive re-forestation measures often cannot compensate for unusually excessive exploitation. Such serious problems are the opposite side of the coin to the various advantages of bioenergy vis-à-vis other regenerative energy sources - energy from biomass can be stored and used as required and it has a high degree of efficiency. When combusted, it releases exactly the same amount of carbon dioxide (CO2) as has been previously absorbed by growing plants during photosynthesis. Thanks to this closed CO2 cycle, biomass is a climate-friendly energy source which doesn't generate any additional greenhouse gases.

Technology
Besides firewood, a number of other solid, liquid and gaseous residual and waste products can be used to generate energy, such as straw, residential waste, vegetable oil, sewage and landfill gas, and fermented substrates of plant and animal origin. Biomass can be used to generate electricity, heat and fuel and is therefore one of the most versatile energy sources.The versatility of this energy source is reflected in its wide range of technological applications. There are many different small heating systems available for heat generation; in Germany they are common in the 15 kilowatt to one megawatt output range. These include firewood, wood chip and pellet heating systems. There are diverse methods for the relatively new practice of using biomass to generate electricity, such as producing steam by burning solid biomass and driving steam turbines or steam engines, or biomass gasification to generate power in the gas turbines of biogas plants. The various technologies that can be used to generate electricity can basically also be used for combined heat and power so that electricity, heat and, if necessary, cooling can be produced at the same time and to very high degrees of efficiency. Block-type thermal power stations, gas turbines, fuel cells and Stirling engines are some of the innovative technologies in the combined heat and power sector. The most important biofuels for powering vehicles at the moment are alcohol fuels, for use in petrol engines and high-powered fuel cells, vegetable oils (mainly rapeseed and sunflower oil in Germany) and biodiesel for use in diesel engines. New processes for generating synthetic biofuels are being developed, such as BTL (biomass to liquid). These processes use all of the plant's biomass and not just the oil or sugar part. This greatly increases the useful potential for biofuels. However, it should not be forgotten that with the increased use of biomass to create energy, its competing uses can increase in respect of one another and of the application areas of biomass in the materials, nutrition and animal feed areas.

Domestic sector
There was a great boom in power generation from biogas in 2006. Compared to the previous year, the amount of electricity fed into the grid increased many times over from 3.2 billion kilowatt hours to around 18.6 billion. High prices for crude oil and natural gas and the crucial support instruments through the EEG, the market incentive programme and the Biomass Ordinance have also contributed to an increase in the use of bioenergy for providing heat. Retailers of wood pellets again reported a doubling in their sales last year in compared to the previous year. Sales of biofuels in 2006 rose from around two million tons to over three million tons. Besides biodiesel, vegetable oil and bioethanol also made up a significant proportion, as in 2005 (source: AGEE-Stat, as of April 2007). The bioenergy industry recorded a total turnover of 8.1 billion euros in 2006. 2.9 billion euros of this was invested in new plants.