Biomass – definition, division, use, risks, trends

Biomass is any organic matter on Earth that is involved in the cycle of nutrients in the biosphere. It is the bodies of all organisms (animals, plants, fungi, bacteria and cyanobacteria), both living and dead, from largest to microscopic.

 

Power biomass

For energy and fuel production only the power-exploitable biomass can be used (energy biomass, sometimes just biomass). Biomass can be described as accumulated solar radiation, though with low efficiency, but with almost zero losses during long-term accumulation.

Division of biomass types

According to Annex No. 1 to Decree No 482/2005 Coll., on the determination of biomass types, methods of use and parameters in supporting the generation of electric energy from biomass, as amended, biomass is divided into three main types:

Agricultural biomass – phytomass grown on agricultural land;
Forest biomass – dendromass, and
Residual biomass - by-products of agriculture and manufacturing industry

 

Agricultural biomass

By the way of energy conversion (According to Annex No. 1 to Decree No 482/2005 Coll., Group 1 and 2) the following can be made use of:

• Specifically grown energy crops that may be:
  • Therophytes: mustard, safflower, amaranth, hemp,
  • Perennial plants: artichoke, knotweed, sorrel;
• Winter and spring non-food crops (cereals, maize, oilseeds, and fibre plants);
• Fast-growing tree species grown on agricultural land (willow, poplar, locust);
• Energy grasses: miscanthus, cane, reed, creeping bent grass;
• Part of agricultural by-products (oil straw, cereals) that are currently abundant due to the reduction of cattle production or
• unused hay produced during the maintenance of meadows and pastures.

 

 

Energy potential of agricultural biomass is set in 2 alternatives with regard to food safety, namely:

• for the maximum possible energy potential with respect to food safety (159.4 PJ)
• according to data on food safety provided by the Ministry of Agriculture (108.8 PJ)

 

Benefits of growing phytomass:

• Landscape maintenance, water retention in the landscape;
• Friendly approach to the environment;
• Effective management of agricultural waste and surplus;
• Reduction of unemployment;
• Use of traditional farming technology;

Agricultural biomass is the most complex component of biomass potential of the Czech Republic. Use of phytomass grown on agricultural land supports the restructuring of our agriculture during the transition from food commodities to alternative technical or energy crops.

Another positive effect of growing alternative crops is that it ensures energy self-sufficiency of the rural areas, targeted regional consumption of generated sources of funding, as well as increased attractiveness of municipal communities.

Benefits of growing phytomass:

The benefits of production can only be used after mastering the difficult logistics and a large number and variety of processing technologies.

 

 

Forest biomass

Forest biomass (according to Decree No 482/2005 Coll. - Group 3) is formed by:

• Firewood;
• Residual dendromass from forestry and wood industry (residual wood matter from logging, improvement cutting, thinning, scrap, and residues from wood processing industry).

 

Energy potential of dendromass is 42.5 PJ (primary energy; calculated based on 15% water content).

 

Conditions for use of forest biomass in the Czech Republic

Since time immemorial Czech forests are mostly economically utilized in accordance with the following basic principles - consistently sustainable management and protection of nature and the living environment. The permanent objective of forestry professionals is to capture the "safe" energy potential of forest biomass.

Current calculations of the potential of forest biomass is based, due to environmental and economic reasons, only on the value of toll revenues, which determine that 20% of forest biomass be preserved on the mined area. The calculations exclude protective forests and production forests, which grow in unsuitable and especially poor habitats.

Use of mining residues should mainly focus on production forests (according to the Forest Act No. 289/1995 Coll.). Under certain conditions it is possible to use wood material from some specific forests (i.e. some military, spa, and water forests), while safeguarding their priority functions.

Conditions for use of dendromass

When using the forest biomass it is essential to consider the high handling and transport requirements, as well as the availability of local resources. Despite that forest biofuel market already exists in our country; however, it is far from established.

 

Residual biomass

Residual biomass (see Decree No 482/2005 Coll., Group 4 and 5) is an essential part of the potential of energy biomass. It is formed by residues, by-products and waste from the primary sources of vegetable or animal biomass.

The principal amount of residual biomass is derived from wood processing industry and pulp and paper industry. As well as of meat industry, other food and spirits industry and municipal waste sorting. Another component is the residual biomass of both crop and livestock production, i.e. straw and excrements of breeding animals. As a separate group we may include sewage sludge and the sludge from specific productions, if they are classified as biomass.

 

Risks of biomass use

Increasing biomass production requires expansion of the production areas or intensification of biomass production. Large financial investments are therefore inevitable, whose return may initially be risky, since at present the production of energy from biomass has difficulty competing economically with the traditional combustion of conventional fuels.

The use of biomass resources in terms of distances and location of sources and energy consumers also remains an issue. This causes complications with the accumulation, transport, and distribution of procured energy.

Power use of biomass

• Direct combustion – heat and electrical energy;
• Cogeneration – electrical energy and heat;
• Production of biogas;
• Production of liquid biofuels;

 

Non-energy – material use of biomass

Material use includes the use of all the residual and purposefully grown biomass as a raw material for industrial production of:

• Paper and wood pulp;
• Building materials (production of building boards, bricks, etc.);
• Chemical and pharmaceutical;
• In new fields that will replace part of their oil products by materials derived from biomass (e.g. „plastics“ based on plant starch);

 

Current status and expected trends

One of the future ways how to clarify the situation and mitigate the risks of using biomass is to adopt good environmental legislation. The Biomass Action Plan, that has already been adopted, has contributed to the consolidation of the view as to how to exploit the potential of biomass in the Czech Republic. The emphasis is being put on mutual coordination of different strategies and plans in individual sectors in which biomass is used namely in connection with the needs of food safety and sustainable development principles.

Non-energy use of biomass will grow in importance, depending on market demand, because in this industry subsidies or incentives are not usual. While there is mainly wood and residual wood biomass currently being processed, the share of agricultural biomass is bound to increase in the future.

In the long run it is necessary to maintain and expand the existing scope of industrial production based on biomass, especially in the paper industry and construction materials industry.

In the future it is important to monitor the trends in the use of biomass with higher added value and seek the prospective and strategically important areas. Then they should be promoted through scientific research projects with an emphasis on applied research as well as the involvement of universities along with industrial and agricultural entities.