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BIOGAS in the Baltic Sea Region

Biogas is produced when organic material (biomass such as manure, food biowastes, grass and silage, sewage sludge etc.) is decomposed in anaerobic digestion process by microorganisms in an oxygen-free environment. Biogas mainly consists of methane and carbon dioxide, but also contains small amounts of hydrogen sulphide and ammonia. Biogas is continuously produced in natural environments such as the stomach of cows and other ruminants, in marshes and bogs and in lake sediments. The active microorganisms in the biogas process can be controlled through substrate addition and keeping the fermenter in a certain temperature range to produce renewable energy from biomass in the form of biogas. In case it has been purified to the same quality level with natural gas, it can be called biomethane. Natural gas and biomethane can both be called methane gases.
The final product of fermentation is a flammable biogas of the following composition, depending of the substrates:
50 – 75% methane (CH4)
25 – 45% carbon dioxide (CO2)
2 – 7% water (H2O)
< 2% oxygen (O2)
< 2% nitrogen (N2)
< 1% ammonia (NH3)
<1% hydrogen sulphide (H2S)
A cubic meter of methane has heating energy content of nearly ten kilowatt hours. Therefore, if the methane content of the gas is 60 %, the energy content of a cubic meter of biogas totals about 6 kWh, the calorific value corresponding roughly to 0.6 litres of fuel oil. Depending on treatment, technologies and commercial needs, the biogas may be either converted into energy and heat by combustion in combined heat and power (CHP) plants or purified to biomethane for being fed into the natural gas grid or used as transport vehicle fuel. At present both options are used and prioritised in different countries, e.g. in Germany in most of the cases the biogas produced is used in combined heat and power plants for the production of electricity in a combined heat and power generation, while in Sweden the biomethane is used as traffic fuel. Modern CHP plants work with an electrical efficiency of about 40 % and heat production efficiency up to 45%. The electricity generated may be used for the process, own needs and for feeding into the mains of the local energy supplier
The advantages of using biogas are cross-sectoral and include e.g. utilizing biowastes from households, communities and agriculture as well as purposeful production of CO2-neutral energy from renewable biomass. Biogas differs from many other bioenergy sources as it is locally-traded and not a subject to international trade like e.g. bioethanol, biodiesel or wood pellets. The local nature of biogas is at the same time a challenge and an advantage – the need for custom-made solutions allows extra attention to case-specific issues, but also means that some solutions may not be easily transferable to other countries. Other problems are difficulty of risk assessment when making rational investments in new technologies and long pay-back time of biogas projects. Also, due to lack of expertise and experience, finding finances for investments, competent partners and well-proven examples is sometimes problematic. Despite that, biogas is showing a growing trend in many countries.

Biogas production and use in BSR

In 2009 8,35 Mtoe of primary biogas energy was produced in the European Union. The progress of biogas sector is evident - in 2008-2009, primary energy growth increased by 4,3%. While potential for biogas production is considerable in many BSR countries, Germany has clear leader role in taking the potential into actual use. About half of the total biogas produced in the EU is registered in Germany. In many other BSR countries the market first has to be opened up. Development of the market depends on policies of EU and individual countries - in countries where different incentives have been introduced, also attractiveness to erect biogas plants has improved essentially, e.g. in Latvia and in Czech Republic
The sources for biogas production vary greatly in the BSR and are closely related to priorities set in national policies. In Germany agricultural substrate takes up huge majority of biogas production while Sweden and Poland have more emphasis on sewage sludge gas. Finland, but also Sweden and Poland have a considerable share in landfill gas.
Primary biogas energy output in BSR countries in 2008 [ktoe], Eurobserver Biogas Barometer 2010
Sewage sludge gas – urban and industrial
Other biogas – decentralized agricultural plant, municipal solid waste methanisation plant, centralized co-digestion plant

EU policy framework

Biogas production has the advantage of reconciling two European Union policies. Firstly it falls in line with the main objective of the Renewable Energy Directive (2009/28/CE) that is aiming for a 20% renewable energy share in gross final energy consumption by 2020. It also meets the European organic waste management objectives enshrined in European regulations (Directive 1999/31/CE on the landfill of waste) that require Member States to reduce the amount of biodegradable waste disposed of in landfills and to implement laws encouraging waste recycling and recovery (Directive 2008/98/EC on waste). Methanisation is considered to be the best environmental waste energy recovery method.

These political ideas have prompted a number of Member States to encourage biogas production and they have set up incentive systems for paying for electricity and heat (feed-in tariffs, green certificates, tenders etc). If the legal promotion did not exist, the technology of biogas generation would currently not be competitive on the electricity and heat market. Consequently, the legal frameworks in the individual EU member states are the most important market factors.