6. Good Practice Example: Biogas in Germany

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1 6. Good Practice Example: Biogas in Germany Key words Energy, Power, Renewables, Biogas, Organic waste, Landfill. Name and location Using biogas as an energy resource for small power plants in Germany Germany is the world leader in heat and power production using biomass and biogas. Biomass-fired co-generation plant Seigen-Wittgenstein in Erndtebrueck The plant uses the left-overs of the forestry industry in the region to produce heat and power. Background, objectives, implementation measures and financing Biogas typically refers to a mixture of different gases produced by the breakdown of organic matter in the absence of oxygen. Biogas can be produced from raw materials such as agricultural waste, manure, municipal waste, plant material, sewage, green waste or food waste. It is a renewable energy source and in many cases exerts a very small carbon footprint. Biogas can be produced by anaerobic digestion with anaerobic bacteria, which digest material inside a closed system, or fermentation of biodegradable materials. Biogas is primarily methane (CH4) and carbon dioxide (CO2) and may have small amounts of hydrogen sulphide (H2S), moisture and siloxanes. The gases methane, hydrogen, and carbon monoxide (CO) can be combusted or oxidized with oxygen. This energy release allows biogas to be used as a fuel; it can be used for any heating purpose, such as cooking. It can also be used in a gas engine to convert the energy in the gas into electricity and heat. Biogas can be compressed, the same way natural gas is compressed to CNG, and used to power motor vehicles. In the UK, for example, biogas is estimated to have the potential to replace around 17% of vehicle fuel. It qualifies for renewable energy subsidies in some parts of the world. Biogas can be cleaned and upgraded to natural gas standards, when it becomes bio methane. Fig. 1: All-rounder biogas: depending on the users of heat or the type of use, biogas can serve a number of purposes.

2 Cost benefit, effects and results achieved Usage of biogas in Germany Germany is Europe's biggest biogas producer and the market leader in biogas technology. In 2010 there were 5,905 biogas plants operating throughout the country; Lower Saxony, Bavaria and the eastern federal states are the main regions. Most of these plants are employed as power plants. Usually the biogas plants are directly connected with a CHP which produces electric power by burning the bio methane. The electrical power is then fed into the public power grid. In 2010, the total installed electrical capacity of these power plants was 2,291 MW. No other country in Europe generates so much power from biogas as Germany: in 2010, Germany led the field with an output of some 16 billion kwh, followed by Great Britain (5.7 billion) and Italy (2.1 billion). In 2012 there were around 7,600 systems with a cumulative capacity of almost 3,200 MW generate 21.9 billion kwh in Germany, thus consolidating the country s position as the international front runner. This makes the German biogas industry particularly strong: in 2012 it provided some 41,000 jobs and is set to generate sales totalling 6.5 billion euros. Biogas in Germany is primarily extracted by the co-fermentation of energy crops (called NawaRo, an abbreviation of nachwachsende Rohstoffe, which is German for renewable resources) mixed with manure. The main crop used is corn. Organic waste and industrial and agricultural residues such as waste from the food industry are also used for biogas generation. In this respect, biogas production in Germany differs significantly from the UK, where biogas generated from landfill sites is most common. Fig. 2: Use of biogas in Germany: development

3 Problems of using biomass for energy This continual trend of renewable energy promotion induces a number of challenges facing the management and organisation of renewable energy supply that has also several impacts on the biogas production. The first challenge to be noticed is the high area-consuming of the biogas electric power supply. In 2011 energy crops for biogas production consumed an area of circa 800,000 ha in Germany. This high demand of agricultural areas generates new competitions with the food industries that did not exist hitherto. Moreover new industries and markets were created in predominately rural regions entailing different new players with an economic, political and civil background. Their influence and acting has to be governed to gain all advantages this new source of energy is offering. Finally biogas will furthermore play an important role in the German renewable energy supply if good governance is focused. Biomass-fired co-generation plant Seigen-Wittgenstein in Erndtebrueck To date logging residues (e.g. crown material) obtained in the forestry industry has remained largely unused. This forestry biomass is of no use in sawmills and the timber material industry and also not in the paper industry on account of its heterogonous nature, and RWE Innogy Cogen GmbH now intends to use it to generate power and process steam. By 2009 the company will be erecting a biomass-fired co-generation plant in the Wittgenstein Industrial Park. The investment volume will be around 25 million euro. Natural events like the hurricane Kyrill as well as regular logging leave behind large quantities of timber biomass in the forests. Its recycling counteracts beetle infestation and the danger of forest fires. The company gears its recovery operations to ecological criteria, thus ensuring that the nutritional cycle of the forests is not disturbed. This opens up a completely new raw material segment. The power-heat co-generation plant is designed for an output of 30 MW thermal and a maximum of 8 MW electric, and it is operated using wood as a fuel. Since the combustion of wood is CO2-neutral, the projected plant will make a major contribution to climate protection. The customer for the steam generated is Vis Nova GmbH, which is erecting a new factory to produce wood briquettes on a neighboring site in the Wittgenstein Industrial Park. The steam is needed to dry and compress the source material of wood. The region also profits from this new approach: the forestry industry in the Siegen-Wittgenstein district now has a new sales segment and new jobs will be created in the power plant as well as in the surrounding domains. By 2020

4 RWE Innogy Cogen intends to erect a total of ten biomass-fired co-generation plants in the state of North Rhine-Westphalia. Fig. 3: Biomass-fired co-generation plant Seigen-Wittgenste. Function Feeding electricity into the public grid under the German Renewable Energy Act (EEG) Supplying the neighbouring pellet plant with process heat Plant components Grate firing with natural circulation boiler Extraction-condensing turbine Wood yard and transport facilities Plant data Thermal output: 30 MWth Electrical output: 5 MWel Biomass input: 90,000 tons t/a Electricity production: 38,000 MWh per year Process heat production: 100,000 MWh per year Planning procedures, involvement of stakeholders and possible participation structures Biogas production in Germany has developed rapidly over the last 20 years. The main reason is the legally created frameworks. Government support of renewable energies started at the beginning of the 1990s with the Law on Electricity Feed (StrEG). This law guaranteed the producers of energy from renewable sources the feed into the public power grid, thus the power

5 companies were forced to take all produced energy from independent private producers of green energy. In 2002 the Law on Electricity Feed was replaced by the Renewable Energy Source Act (EEG). This law even guaranteed a fixed compensation for the produced electric power over 20 years. The amount of around 0.08 euro gave farmers the opportunity to become energy suppliers and gain a further source of income. The German agricultural biogas production was given a further push in 2004 by implementing the so-called NawaRo-Bonus. This is a special payment given for the use of renewable resources, i.e., energy crops. In 2007 the German government stressed its intention to invest further effort and support in improving the renewable energy supply to provide an answer on growing climate challenges and increasing oil prices by the Integrated Climate and Energy Programme. Lessons learnt practical recommendations The size of power plants has grown rapidly over the years. While the average size of a biogas power plant was 60 kw in 1999, it was 300 kw only 10 years later (2009). The reason for this lies in the decreasing specific cost of bigger plants - about 50% lower for a 300kW plant than for a 60kW plant. Today, the profitability of biogas plants in Germany depends greatly on the potential to sell heat as well as producing electricity. The heat output of combined heat and power (CHP) generators is used to provide hot water for community heating systems for households, schools, public swimming pools etc. Furthermore, special bonuses, such as bonuses paid for the use of renewable raw material, are also important for the profitable operation of the plants.