The depletion of conventional, non-renewable fuels, and the irreparable damage caused to the earth's atmosphere from the combustion of fossil fuels, from the emission of carbon dioxide (CO2), which contributes to global warming, has made it imperative to switch to sustainable and environmentally friendly energy sources, such as RES (renewable energy sources). One of the RES is also biomass.

The term biomass means the energy source derived from organic matter. Biomass includes any material produced by living organisms (such as wood and other forest products, crop residues, animal wastes, wastes of food industry, etc.) and can be used as fuel to generate heat and / or electricity.

The fact that during the energy exploitation of biomass, the amount of carbon dioxide (CO2) emitted into the atmosphere equals the amount of CO2 absorbed from the atmosphere during its creation, classifies it as RES. Therefore, the total carbon dioxide balance is zero and biomass does not contribute to the greenhouse effect.

The development that has occurred in rural technologies in recent years, led to a reduction in the cost of biomass as raw material, which translates to cheaper production of energy.

Finally, the absence of sulfur from biomass contributes significantly to reducing emissions of sulfur dioxide (SO2), which is responsible for acid rain.

There are two types of biomass:

• The residual forms (any kind of plant residues, animal wastes and trash – waste water).
• The biomass produced from energy crops.