The biomass concept is very extensive and includes/understands all type of organic matter, as much of vegetal origin as animal, and is formed thanks to the photosynthesis directly (like vegetables) or indirectly (by the digestion of vegetables).
The biomass is formed by forest firewood, shrubs, remainders, rest of pruning, agricultural remainders like the straw, remainders of lumber industries, agro-alimentary wastebaskets and, dung, urban remainders of agroganaderas operations, solid remainders and urban residual waters among others.
Most of these components, not to say the totality, can be used like fuel, or of direct form (burning them) or transforming them to other fuel forms like biogás or biocombustibles.
To use the combustible biomass is a renewable resource since it takes place at the same speed of the consumption, as long as the consumption is controlled and the sobreoperation of the natural resources is avoided.
Unlike fossil fuels, the biomass is respectful respectful with the environment, since it does not emit effect gases conservatory of uncontrolled form.
When biomass combustion, it releases CO2 to the atmosphere, the same CO2 that absorbed of her during its growth, if it is vegetal organic matter, or which they absorbed the plants that ingested, if animal is organic matter.
If it is consumed of sustainable way, the cycle is closed and the level of CO2 to the atmosphere stays constant, so that its use does not contribute to generate the climatic change.
And not only that, but that with its consumption replaces the fossil fuel consumption, thus avoiding to generate emissions that did not comprise of the atmosphere previously and that is causes of the climatic change.
In addition, to use combustible biomass is beneficial for the surroundings: it eliminates remainders helping to diminish the fire risk and the accumulation of remainders, and treats residual waters and purines that is source of contamination of the subsoil and underground waters.
Pellets
Pellets are remainders coming from forest cleaning and lumber industries that are crushed and turned to shavings. Once dried to diminish the humidity level and possible resins, they are pressed in form of small cylinders.
Pellets is an evolved application of the biomass, is clean, of easy handling, occupies little space and allows the capacity to autoalimentar itself to the stoves that use them, working independent form that during hours.
In addition they are very ecological, since they give utility to a remainder and they avoid the cutting of trees for the heating, as it is the case of the firewood.