Options for Sustainable Heat Use of Biogas Plants Dominik Rutz, Rita Mergner WIP Renewable Energies, Munich, Germany
Contents 1. Biogas situation in Germany 2. Characteristics of heat from biogas plants 3. Overview: Heat use options 4. Examples 5. Innovative concepts 6. Example: Feasibility check in Germany 2
Growth of Biogas Plants in Germany Source: German Biogas Assoziation (FVB) 3
Typical biogas plant in Germany Average Size: ~500 kwel Biogas use: electricity Feedstock: mainly corn silage, but also manure, waste, etc. 4
Learning effect: Reasons why German biogas plants struggled in 2007/2008 OUT: wasted heat OUT: electricity EEG IN: only corn silage; High corn prices in 2007/08 5
Renewable Energy Sources Act New biogas plants (from 2012) need to prove 60% heat use Thereof 25% can be included for digester heating Accepted technologies for the proved heat use are included in a positive list 6
Contents 1. Biogas situation in Germany 2. Characteristics of heat from biogas plants 3. Overview: Heat use options 4. Examples 5. Innovative concepts 6. Example: Feasibility check in Germany 7
Challenges for heat use from biogas plants Challenges: Remoteness: Biogas plants are often on the field Seasonality: more heat available in summer due to less digester heating Heat quantity: average plant sizes of 500 kwth Heat quality: 80-450 C depending on the CHP Advantage: The heat is very cheap 8
Heat quality Examples for needed temperature levels: Hot water supply: 50-80 C Heating: 50-80 C Rankine Cycles (ORC): 60-565 C Drying for agricultural products: 60-150 C Available heat levels from CHP units: 3-5% Radiation losses (not usable) 1-3% Lubrication oil: 80-90 C 30-49% Engine cooling (cooling water): 80-90 C 50-60% Exhaust gases: 460-550 C 9
Heat supply curve for a 600 kw CHP unit Wärmequalität Source: BiogasHeat Handbook 10
Wärmequalität Heat demand: load duration curve Source: BiogasHeat Handbook 11
Contents 1. Biogas situation in Germany 2. Characteristics of heat from biogas plants 3. Overview: Heat use options 4. Examples 5. Innovative concepts 6. Example: Feasibility check in Germany 12
Biogas Biogas pipeline (optional) Upgrading to biomethane Biomethane Combustion in a (satellite) CHP unit Natural gas grid CO 2 Power Heat Transport Natural gas substitute e.g. ORC, Stirling Heat exchanger Absorption cooling e.g. air dryer Power Heating Cooling Drying Examples: District heating Aquaculture Greenhouses Agro industry Examples: District cooling Fish industry Diary industry Other food storage Examples: Woodchips Sawdust for pellets Log wood, Digestate Cereals, Herbs, Spices
Most frequent Heat Use Options for Biogas Plants The most common heat use options for biogas plants are: 1. Direct heat use in mini heating grids 2. Biogas pipeline to sattelite CHP 3. Drying of woodchips, cereals, digestate Source: Thermaflex Isolierprodukte GmbH 14
Further Heat Use Options for Biogas Plants Biogas upgrading to biomethane Acclimatisation of stables (pigs, chicken) Cooling for dairy products, fish Aquaculture ORC Organic Rankine Cycle Greenhouses Heat transport in containers http://www.garnelenhof.de All options are described in our handbook! 15
Contents 1. Biogas situation in Germany 2. Characteristics of heat from biogas plants 3. Overview: Heat use options 4. Examples 5. Innovative concepts 6. Example: Feasibility check in Germany 1 6
Positive list (EEG 2012) in Germany Heating, hot water supply, cooling of buildings up to 200 kwh/m³/year Heat injection in heating networks of minimum length of 400 m (losses < 25%) Process heat for the industry Drying of wood: 0.9 kwh per kg wood EEG = German Renewable Energy Sources Act 17
Mini district heating systems Source: Thermaflex Isolierprodukte GmbH Dominik Rutz Dominik Rutz Problem: O en no heat consumer in the vicinity, or too far away 18
Drying of woodchips Dominik Rutz Dominik Rutz EEG 2012: the drying of wood for use as a material or as energy up to a heat use of 0.9 kwh per kg of wood 19
EEG 2012: Heating of livestock stables (upper limits per year): aa) poultry fattening: 5 kwh/ animal space bb) sow keeping: 350 kwh/ animal space cc) piglet husbandry: 75 kwh/ animal space dd) pig fattening: 45 kwh/ animal space 20
Example: Process heat for Aquaculture Niche application Water connection Knowledge Market for products Fish/shrimp price Avaliable technologies Investment costs Legislation http://www.garnelenhof.de http://www.garnelenhof.de 21
Positive list (EEG 2012): Glasshouses Dominik Rutz Dominik Rutz Dominik Rutz 22
Dominik Rutz Dominik Rutz Dominik Rutz EEG 2012: process heat for the hygienisation or pasteurisation of fermentation residues requiring hygienisation or pasteurisation under applicable laws 23
Belt dryer; Quelle: STELA Laxhuber GmbH Dominik Rutz Dominik Rutz EEG 2012: process heat for the processing of fermentation residues in fertiliser production 24
Mobile heat transport in containers Latent heat storage: PCM (Sodiumacetat, Bariumhydroxid) Wikipedia Pocket heater Train waggon Thermodynamic storages: Zeolithe Container LaTherm GmbH Wikipedia 25
Low temperature levels (48/78 C) Logistical challenge Maximum distance: 30 km Minimum heat capacity 250 kw th of the biogas plant Minimum 125 kw th heat demand Only few experiences Source: TransHeat GmbH 26
Additional electricity production Source: GE Energy Source: GE Energy EEG 2012: the use of waste heat from biomass installations in order to generate electricity, in particular in Organic Rankine and Kalina cycle processes 27
Exhaust gas turbine (Source: Schnell Motoren AG) 235 kw el dual fuel engine with integrated 30 kw el exhaust gas turbine 28
Absorption cooling Dominik Rutz Source: BiogasHeat Handbook e.g. ice production, fish industry, food storage, acclimatisation of stables, butchery/slaughtery, brewary 29
Contents 1. Biogas situation in Germany 2. Characteristics of heat from biogas plants 3. Overview: Heat use options 4. Examples 5. Innovative concepts 6. Example: Feasibility check in Germany 3 0
Upgrading to biomethane Dominik Rutz Dominik Rutz 31
Biomethane transport in containers Dominik Rutz Borås Schweden 32
Biomethane in transport Dominik Rutz Linköping, Sweden Dominik Rutz 33
Biogas contributing to power grid stability New tool in the EEG 2012: direct selling Quelle: http://www.next kraftwerke.de/virtuelles kraftwerk next pool/biogas this has implica ons on the heat produc on, use and storage 34
Power-to-Gas Source: BiogasHeat Handbook 35
Contents 1. Biogas situation in Germany 2. Characteristics of heat from biogas plants 3. Overview: Heat use options 4. Examples: Positive list in Germany 5. Innovative concepts 6. Example: Feasibility check in Germany 36
Feasibility check: Analysis of the situation (In Germany 10 feasibility checks are made in total) Capacity: 190 kwel und 212 kwth 37
Feasibility check: Current heat use 38
Feasibility check: Heat use options Options: Drying facility: woodchips Biogas pipeline to a sattelite CHP unit Mini heat grid Important figures: Heat loss per m in % Transported heat per m pipe: kwh/m of pipe and year 39
Thank You! Dominik.Rutz@wip-munich.de www.wip-munich.de www.biogasheat.org www.urbanbiogas.eu www.big-east.eu www.biogasin.org 40