Biomass to Energy in Germany Past – Present – Future an Overview

Prof. Dr. Bernd Stephan University of Applied Science Bremerhaven, Germany

Structure of Energy Consumption World - EC25 – Germany (IEA/BEE-eV) Natural Gas Nuclear Renewables Coal Mineral oil World (2003) 19.52

2.54

20.34

13.86

43.71

Total (TWh/year) 84 744 EC25 (2003) (%) 28.8

6.43

8.57

9.05

47.15

10080 Germany (2005) 32.1

5.7

6.4 18.1

37.7

2 936

Energy Consumption Germany 2002 to 2005, BEE-eV Natural Gas Nuclear Renewables Lignite Mineral Coal Mineral Oil 2002 21.7

12.6

3.4

11.6

13.2

37.5

2004 % 22.4

12.6

3.6

11.4

13.4

36.4

2005 32.1

5.7

6.4

8.7

9.4

37.7

Utilization of Renewables in Germany in 2004 (%)

Biomass solid Biomass liquid Biomass gaseous Solar thermal Geothermal Waste Biodiesel Rape oil/ethanol Hydropower Wind energy Photovoltaic 44.1

0.1

6.3

1.8

1.1

6.4

7.2

0.4

14.7

17.5

0.3

Primary Energy for Generating Electricity in Germany • • • • Lignite Nuclear Power Coal Renewables (including hydropower) • • Natural gas Fuel oil 27% 27% 24% 12% 9% 1%

German Energy Imports 2005 Source: IEA, Federal Office for Economy Germany Mineral oil Natural Gas Coal Russia Norway Great Britain Russia Norway Netherlands South Africa Poland Russia 34.1% 14.7% 12.7% 42.6% 30.1% 22.5% 22.9% 22.0% 15.7%

What is meant by „Biomass“ ?

• • • • • Materials produced by metabolic activities of biological systems and/or products of their decomposition or conversion The materials are based on carbon compounds The chemical and energetic value of those materials is based on the carbon-carbon and carbon-hydrogen bond Biomass suitable for utilization must have a net heating value Biomass is collected and stored solar energy

Sources of Biomass • • • • • agriculture residues from forestry, specific industries (e.g. furniture production, saw dust), food processing solid municipal and industrial wastes used wood e.g. from old furniture, used timber marine systems: the oceans of our world contain much more biomass than existing on the continents (but they are not regarded as a source of biomass for energetic utilization)

Biomass contributions to energy supply in Germany: thermal energy • • • • • Wood Wood residues Municipal waste Sewage sludge Agricultural waste

Biomass contributions to energy supply in Germany: electrical energy • • • • • Wood Biogas Waste incineration Fermentation of sewage sludge Biogas from industrial waste water

Biomass Conversion

• • • • • Microbial treatment Thermal treatment Chemical treatment Combinations Mechanical processes

Microbial Treatment • • • • Long traditions in many cultures in the field of food processing e.g. beer brewing, alcoholic fermentation, preservation technologies as lactic acid fermentation Waste treatment in agriculture and food industry by aerobic treatment (composting) and anaerobic fermentation Treatment of municipal and industrial waste water (Pre)Treatment of solid waste containing organic materials

Alcoholic fermentation Agriculture: production of carbohydrates as raw material Fermentation and destillation: ethanol Processing and recycling of residues and residues

Aerobic Processes Agricutural wastes: Traditional method: composting Treatment of solid urban waste: Technology with good prospects Pretreatment of hazardous waste Treatment of gaseous phases for desodorizing (e.g. compost filters in fish industry)

Composting

Composting is a traditional technology in agriculture and gardening. Today there are processes of treatment of municipal waste which make use of the heat of composting for drying the solid waste before separation under investigation. There is no significant contribution to the energy supply of Germany by composting of biomass.

Composting of mixtures of municipal and organic waste of food industry is implemented in many cities

Anaerobic Digestion: Biogas History • • • • • History in Germany starting with utilization of „marsh gas“ in the 19th century: gas tight drums with an diameter of about 2 to 3 meter were placed upside down into the wet lands for gas collection and gas utilization for cooking – similar to the Indian Gabor Gas plant Around 1920 trucks of public services were operated with compressed biogas from digestion of sewage sludge – in the fifties of the 20th century this was given up due to low cost mineral oil In the fifties of last century some farmers built biogas plants for the treatment of aninmal wastes – the technology was based on different principles and processes The oil price crisis in the seventies stimulated broad activities on the research and implementation side of agricultural biogas plants and resulted in optimized plant design and process performance. About 200 plants were bulit and operated at that time, but could not compete with the market prices for gas or liquid hydrocarbons.

The energy policy of German Federal Government now subsidies the utilization of renewables – as a result the market for big biogas plant goes up (most of them are connected to cogeneration plants)

• • • • • • • Potential of Biogas Potential of total (PJ/year) electric. (TWh/a) 96.5

7.2

Animal excreta 4.5

Vegetable residues from agriculture 3.0-5.3

Wastes from Industry 0.3-0.6

Waste from parks and gardens 0.3-0.6

Organic municipal waste 0.6

Energy crops 3.7

TOTAL 12.7-15.3 65-113 6.4-12.2

6.4-12.2

12.5

78.7

265.1-324.9

4.9-8.5

0.5-0.9

0.4-0.8

0.9

5.9

19.8-24.2 (billion m 3 /a)

Thermal and Chemical Processes

• • • • Combustion Pyrolysis Chemical Prozesses: hydrogenation, transesterification Process combinations (e.g. the Choren Process: BTL „biomass to liquid“)

Mechanical Processes

• • • • • Filtering Dewatering Sedimetation Chopping/Cutting Pelletising

Conversion Technologies – state of the art • • • • Biogas Incineration Pyrolysis BTL (Biomass to liquid)

Anaerobic Digestion of Sewage Sludge Sewage sludge is fermented and used to cover the energy demand of the waste water treatment plants. By doing this those plants need no external energy. The biogas is used for cogeneration of heat for the digesters an electricity for the aerobic waste water purification process (energy for pumping and aeration of the waste water).

Wood Incineration Units • • Normally chopped wood or chopped woodv residues are used as feeding materials for large cogeneration plants For the heating of households pelletised materials are available. By using them the incineration process can be operated automatically. The cost for the pelletized wood in relation to mineral oil come to about 2/3

Wood Incineration Plants - practical examples -

200kW-Plant for heat production • • • • • • Feed: chopped from forestry, 50 kg/h Density of feed material: 0.25 kg/liter Efficiency: 0.85

1600 hours of operation per year Feed need per year: 380 m 3 Storage capacity for 2-3 weeks: 40 m 3

19.5 MW – Plant for gerating heat and electricity • • • • • Input „fresh“ and old wood chops, 5.33 t/h max Steam production: 25.5 t/h at 47 bar/430 o C), steam outlet from turbine: 2.2 bar/126 o C Operation 8000 hours per year Energy output electrical from 3.8 to 5.1 MW depending on heat delivery for the households Energy output thermal: maximum 10 MW

Wood – a big potential in the forests • • • • In Germany there are growing about 60 to 100 millions of m 3 wood per year, that can be harvested That is an energtic equivalent of about 1.5 to 2.5 TWh/a Compared to the actual energy consumtion of Germany this is a potential of 50 to 80 % Actual energetic utilization of wood comes to 0.09 TWh/a only

Market prices for selected materials -current prices • • • • Wood chops Wood pellets (dry) Wood, fresh Biodiesel based on rape oil 50€ per 1000kg 200€ per 1000kg 50-80 € per m 3 0.95 € per Liter • • Wheat Mineral oil 100 € per 1000kg 650 € per 1000 Liters

Energy content of wood based substrates average data water content calorific value oil equivalent Pieces Pellets Chops Wheat (%) 20 10 20 15 (kWh/kg ) 4 5 4 4 L oil/m 165 325 100 3 Saw dust 40 2.6

70 ---------------------------------------------------------------------------------------------- 400 L/1000 kg

Waste Incineration - Example: Bremerhaven • • Capacity: 315 000 tons/year Energy output: 100 000 000 kWh/year electrical and 250 000 000 kWh/ year thermal

Biomass as fuel, biomass to fuel • • • • • 1 Vegetable oil, fresh and used 2 Modified vegetable oil, biodiesel 3 Bioethanol 4 Biogas 5 Synthetic fuels

Implementation Biofuels

1 to 4: proven technology of production and application 5: Under intense investgation with great potential: „sun fuel“, „BTL, Biomass to Liquid“

Biomas To Liquid: SunFuel (Choren) • • • Modified „Fischer-Tropsch“ process: gasification of substrates at 400 to 500 o C with lack of oxygen, further oxidation above ash melting point, mixing of resulting gas mixture with solid carbon residues to produce a raw gas for furher specific synthesis (similar Fischer-Tropsch) 15 000 ton/year pilot plant is under operation Cooperation with Shell, based on Gas to Liquid process, operated in Malaysia

The Hydrogen Problem

Methane „Mineral Oil“ „Mineral Coal“ Biomass C 0.75

0.85

0.83

0.50

H 0.25

0.15

0.05

0.07

*) fractions by weight, rough figures O*) 0.12

0.43

Potential for SunFuel from… (million tons per year) • • • Forestry Unused straw Energy crops 2.5

4.0

3 to 6 • • Biomass available total (Germany) EU 25 30 115

Fuel Consumption (million tons per year) • • 2005 2020 (exp) 2005 Biodiesel (est.) 2020 Biodiesel (exp.) 50 44 1.4

11.1

Future The future development will be based on increasing production of energy crops, optimized utilization of organic residues and on thermal chemical treatment of organic matter to produce gaseous and liquid fuels.

There are lot of estimations for future contributions of biomass to energy supply, they will come to at least 20 or 30 percent until 2020.

Windenergy in Germany 2005 German Association for Windenergy • • • • • Total installed capacity 18 400 MW Number of converters 17 5784 Installed in 2005: 1049 new plants with a total capacity of 1800 MW New installations expected for 2006: 1500 MW Increasing market for German export

Proposed Future Installation of Power Plants in Germany - not from Renewables • • • Capacity Capacity Total Investment 23 000 MW (2012) 40 000 MW (2020) 40 billion €