What is biomass?
The term biomass is not used uniformly because a homogeneous basis of definition is lacking. Today, biomass is commonly understood as the totality of all living and dead plant and animal organisms. This refers both to entire units, e.g. a tree, and to parts of it, its branches, leaves, foliage, etc. Their quantity (mass) is traditionally expressed in grams, kilograms, tons or gigatons per habitat. Either globally or only for small, manageable ecological sub-areas.
How and where is biomass created?
Biomass is created primarily by photosynthesis (conversion of solar energy and carbon dioxide) to plants. Secondarily through the use of these plants for the formation and nourishment of organic living beings. In this respect, the statement that biomass is ultimately nothing more than stored solar energy, which can be read again and again, is correct.
Biomass consists of approximately
- 82 % from plants,
- to 13 % from microorganisms
- and to 5 % from animals and fungi.
Animals here include humans, whose total makes up only 0.01 % of the biomass.
What is biomass composed of?
Biomass consists of a large number of chemical-organic compounds. First and foremost are the carbohydrates (sugars). They consist of carbon, oxygen and hydrogen. Then come the fats (lipids, oils), which are composed of the same basic building blocks, but contain much less oxygen and are therefore considerably more energetic. In addition, there are proteins, which are of considerable importance as forming structural elements in animals and plants. In addition to the three basic elements already mentioned, proteins also contain nitrogen and sulfur. In addition, there are other elements such as phosphorus, magnesium, potassium, iron, copper, etc. in small quantities.
From biomass to bioenergy
When we talk about energy production from biomass, we are talking about renewable energies. For example, biogas can be produced from biomass. Bioenergy is extremely diverse. It ranges from agricultural use from corn and rapeseed, to fast-growing woods and the use of waste and residual materials from agriculture, households and industry. The current great importance of biomass has to do with its high potential as a raw material for renewable energies.
Humans use biomass as biogas (Biomethane) for electricity and heat generation, as fuel from vegetable oils (biodiesel) and for pellets, wood chips and logs for electricity and energy generation. The latter form is considered CO2-neutral when burned because only as much CO2 is released as was bound during the creation of the biomass.
Bioenergy from waste and residual materials
However, biomass as the basis for energy production is not available in unlimited quantities. Its expansion increasingly collides with the production of food. In contrast, however, there is the possibility of producing bioenergy from waste and residual materials. This includes municipal waste such as food scraps and market waste, but also industrial residues from food production. There is also great potential for the production of bioenergy, which has been little exploited to date, in the use of forest residues as well as straw and animal excrement.