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Economic and technical aspects of biogases and their injection, growth potential for biomass/biogas in Germany. Uwe Klaas DVGW e.V., Bonn, Germany. European directive 2003/55/EC. Adopted on 26 June 2003 by the European parliament; Scope: natural gas liquefied natural gas biogas
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Economic and technical aspects of biogases and their injection, growth potential for biomass/biogas in Germany Uwe Klaas DVGW e.V., Bonn, Germany
European directive 2003/55/EC • Adopted on 26 June 2003 by the European parliament; • Scope: • natural gas • liquefied natural gas • biogas • gas from biomass • all other types of gases that can meet necessary quality requirements for access to the natural gas system. • Member States should ensure that, taking into account the necessary quality requirements, biogas and gas from biomass or other types of gas, are granted non-discriminatory access to the gas system, provided such access is permanently compatible with the relevant technical rules and safety standards.
Gases within scope of the MARCOGAZ recommendation “Injection of Gases from Non-Conventional Sources into Gas Networks” • Gases from thermal or fermentation processes: • Biogas from agriculture; • Sewage gas; • Landfill gas; • Coal-bed methane and coal mine methane; • Hydrogen-rich gases from gasification of e.g., biomass, or other chemical processes • Gases (“Biosyngas”) from gasification processes based on biomass as “energy plants”; • But also the “classical” gasification of coal is a limit case: is that process still “conventional”? • Hydrogen produced from electrolysis (generally using renewable energy as e.g. hydro power, solar power or windmills).
Indicative composition of different raw gases Source: MARCOGAZ recommendation
Indicative properties of different raw gases Source: MARCOGAZ recommendation
Treatment Depending on the utilization of the gas its treatment is required. This will generally include: • Drying of the gas (always); • Desulfurization (nearly always); • Removal of inert gases as CO2 (nearly always); • for gases deriving from fermentative processes eventually removal of biogenic substances by filtration (often not specially required, being a side effect of desulfurization); • for gases deriving from thermal processes often methanisation (final products of many thermal gas production processes are for the best part hydrogen and carbon monoxide); • Odorization
Injection of biogases • Bio- and sewage gases may be treated to be used either as augmentation gas or as exchange gas for natural gas. The technical conditions shall be laid down on national base, e.g. in Germany by DVGW code of practice 262. • To achieve this, the relevant characteristics of the base gas (natural gas) in the pipeline in which shall be injected shall be regarded. In Germany, these would be the values for natural gas H or L as given in DVGW code of practice G 260. • The injection of biogases and other non-conventional gases shall be performed indiscriminative in accordance to the existing legislative requirements.
Gas meets specs? Or doesn‘t? • Biogases may be added in two different ways: • As exchange gas: the biogas is treated to a quality equivalent or near the quality of the natural gas, i.e. fully substitutable. Such treatment is of course more expensive, but offers the possibility of access to several biogas producers as long as the pipeline capacity allows. • As augmentation gas: the biogas is not fully treated, i.e. does not meet the specification of the natural gas. Still, for a single producer access may still be possible if the resulting gas mixture meets the specification, depending on agreement between biogas producer and grid operator. However, addition of another biogas off specs might result in the entire gas mixture to become off specs; thus, a case of discrimination would result.
Utilization in gas supply (German case) • In addition to the requirements for natural gas as stated in DVGW code of practice G 260, the following requirements exist for the injection of biogases : • From DVGW G 262: • max. 6 Vol.-% CO2, • max. 5 Vol.-% H2; • from DVGW G 685 (Gas billing), 5.4.2: Variation of the gross calorific value of the gas mixture over a billing period in a grid with more than one gas quality not exceeding 2 %; • Proof of hygienic harmlessness; • Pressure at the level of the pipeline into which is injected.
Criteria for biogas injection • Continual injection of gas shall be possible Limitations by minimum gas sales (seasonal differences) • Taking the local structure of the gas grid into account (Mixing zones and zones with floating zero point?) • Good blending of biogas and natural gas / Plug formation at zones with floating zero point • Local clients of the gas (Sensible industrial clients?)
Adding propane/air ? • In order to adjust the Wobbe index and the calorific value it may be necessary, depending on the local gas quality, to add propane and/or air (CO2 removal may not be sufficient) • Questions arising from addition of propane: • Is condensation possible? • Will the methane number change for gas engines? • Remuneration? • If the law does not provide remuneration: • a) How can the addition of propane be measured? • b) Is this energetic part marketed separately? • In the nearer future, many grids operated on natural gas L will be transformed to deliver natural gas H– when installing an injection plant this should be considered early.
Examples for the injection of biogases • In south-western Sweden some biogas plants are operated by the regional gas supply company Sydgas. The treated gas is completely injected into the gas grid. • A Swiss company (Kompogas AG) offers biogas plants comprising a closed fermenter using the content of the “green bin” as substrate. Some of these plants are operated in Switzerland, others in Germany and other countries. In the Zurich area, the gas of three such plants is treated to a quality comparable to the natural gas in the grid and injected into the local gas grid. • Since December 2006 also in Germany 2 plants comprising injection into the natural gas grid are in operation (Pliening/Bavaria and Straelen/North Rhine region). A further dozen of plants is either under construction or in planning, mostly, but not exclusively on initiative of local gas supply companies.
Biogas plant Pliening Source: Own pictures Uwe Klaas
Biogas plant Laholm/Sweden Biogas production/ Grid access pipeline
Okay, now we‘ve got that stuff in the grid. How much to expect?
BGW/DVGW – study“Analysis and Evaluation of possibilities for utilization of biomass in Germany“ - Objectives and basic questions • Evaluation of the biomass potential in Germany 2006 till 2030 • Techniques of production, treatment and injection of biogas • Possibilities of gasification of wood as a source of bio-methane • Costs evaluation of the utilization of biogas for the production of either electric power, heat or vehicle fuel in comparison to other uses of biomass • Environmental effects of the use of biomass
Solid fuels or substrates* for biogas Bioethanol Used as such RME/Biodiesel Usable acreage till 2030 *These acreages may be used either for growing solid fuels or for biogas substrates Total agricultural acreage : approx. 11,8 Mio. ha (roughly constant)
Industrial and commercial waste material 5% Municipal waste 11% Harvest residues, manure, straw, grass 51% Energy plants 33 % The situation today • Biogas production almost exclusively by fermentation (recently ca. 3500 plants in Germany) • Acreage for plant cultivation for the production of biogas: 550 000 ha • This includes for corn (45 t/ha) with a biogas yield of 180 m³/t with 55 % methane in the raw biogas a potential of 2,4 Bill. m³/a methane = 24 Bill. kWh/a (86,4 PJ/a) by reproducible raw materials • Total potential 72,2 Bill. kWh/a (260 PJ/a) Biogas potential distribution according to origin
Total biogas potential Energy plants max. Energy plants Manure Other waste material Gülle Development of the biogas potential until 2030(Results of biomass study) Approx. 10% of expected German natural gas consumption in 2030 • Conditions: • Complete use of the biogas potential for grid injection • Reasons for growth: • Technical progress at plant level • Increased acreage efficiency in agriculture • Optimized fermentation of biomass Total potential biogas production and injection (Bill. kWh/a) • Wuppertal institute expects that approx. 60% of the technical potential may be realized. • Development path rather dependant from fixed conditions and subsidizing. Source: Study of Wuppertal institute
Tomorrow Biogas (Direct power production) Biomethane Today Natural gas pipeline Biogas treatment Direct power production CHP CHP New utilization paths: Heating market Input: -manure, sewage -agricultural raw material (e.g. corn) -organic waste Fuel sector Expected biogas potential Future cooperation of agriculture and gas industry required Bio natural gas (treatment + injection) Biogas production
Expected biogas potential • Acreage competition • Biomass action plan: + in the beginning, sufficient potential for further growth is present. • + potential not used so far must be developed – as e.g. derelict land, small private forests + industrialized countries with a large population will depend on imports from other EU member countries and from countries outside the EU. • ALARM! Beer prices already increased in Bavaria – barley being used for biogas production!
Remuneration in accordance of use Markets for utilization Power market EIL* / CHP law Heating market Bio-natural gas no support Fuel market Taxadvantage *EIL: Energy injection law Bio-natural gas: markets of use
Scheme of an biogas production plant Source: Biopact, Brussels
Potential additional hazards of biogases • The following kinds of hazard have to be taken into account: • hazards on human health of end-users and for employees of e.g. the gas industry: • direct toxicity in case of leak in a semi-confined environment; • indirect toxicity by combustion products; • water pollution in case of injection in subterranean storage; • air pollution; • hazards on gas networks integrity: • Corrosion; • clogging of pipelines and safety devices; • hazards to the safe operation of gas appliances: • Corrosion; • clogging of safety devices • undue change of combustion properties.
H-Gas or System barrier L-Gas Augmentation gas Compressor Control devices H-Gas or V L-Gas Components Blender and processes Exchange gas Cleaning + H-Gas or Treatment Production L-Gas Control devices Compressor H-Gas H-Gas or or Local utilization V L-Gas L-Gas Gas supply Laws, directives, |--------------------------------> Methods of treatment EN ISO 13686 technical rules Safety data sheet for natural gas and literature for the respective type of NCS Schematic example for the injection of gases from non-conventional sources into natural gas networks
Desulfurization • Regeneratively produced gases may also be desulfurized using well established methods as e.g. the use of gas cleaning mass (iron ore). • In agricultural biogas plants the major fraction of the sulfur is precipitated by injection of a certain volume of air into the gas volume of the fermenter. • More professional and applied in many smaller treatment plants is the reaction of hydrogen sulfide with oxygen and iodine doted active charcoal to result in elementary sulfur. However, after some time the charcoal needs replacement and safe disposal. • Another method applied is the dry desulfurization of the gas by reaction of hydrogen sulfide with iron hydroxide and oxygen which also yields elementary sulfur.
Methane enrichment/ CO2-removal • Most applied methods are the pressurized washing with either water or organic solvents, and the pressure swing absorption (PSA). • Dry methods utilize molecular sieves, active charcoal or membranes for the removal of the inert gas components.
Drying of the gas • For nearly all applications the gas needs to be dried, depending on the choice of the other treatment methods – if dry or wet method – either at the beginning or at the end of the treatment process. For smaller plants, often cryogenic methods are applied, for larger ones e.g. glycol washes.
Additional potential hazards associated with landfill gas and countermeasures applied Source: MARCOGAZ recommendation
Additional potential hazards associated with biogas and countermeasures applied Source: MARCOGAZ recommendation
Development of energy potential of reproducible raw materials till 2030 • Assumed increase of productivity: 2% p.a. • Acreage for the production of bio diesel is assumed as more or less constant (Cultivation of rape seed for the production of bio diesel) • Acreage increase for the cultivation of wheat for the production of bio ethanol up to 250 000 ha until 2020
Gas quality requirements in different countries Source: MARCOGAZ recommendation
Advantages of bio-natural gas in comparison with other regenerative energy resources
Power from mix Power from natural gas Power from biogas Heat from mix Heat from biogas Bio-natural gas for CHP - Specific greenhouse gas emissions in 2010
Bio-natural gas: markets of use Remuneration in accordance of use Markets for utilization Power market EIL* / CHP law Heating market Bio-natural gas no support Fuel market Taxadvantage *EIL: Energy injection law
Sustainability with bio-natural gas in traffic:Achievable kilometreage with the energy of one hectare Bio ethanol (from grain) 2.500 l Bio diesel1.550 l Rapeseed oil1.480 l BtL (Biomass-to-Liquid)4.030 l Bio-natural gas3.560 kg *Bio-natural gas from by-products (rapeseed cake, slurry, straw) vehicle fuel consumption: Otto engine 7,4 l/100 km, Diesel engine 6,1 l/100 km Bio-natural gas as vehicle fuel Source: Fachagentur Nachwachsende Rohstoffe
Bio-natural gas: markets of use Remuneration in accordance of use Markets for utilization Power market EIL* / CHP law Heating market Bio-natural gas no support Fuel market Taxadvantage *EIL: Energy injection law
Example: House equipped with natural gas recondensing boiler Specific costs to avoid CO2- emissions Insulation:very high additional investments, long durability Environmental heat (solar, heat pump):significant additional costs Bio-natural gas:lowest costs despite higher carburant costs Energy requirement/ Insulation level Bio-natural gas as heating carburant Specific costs of bio-natural gas to avoid CO2-emissions are significantly lower for new buildings
The German gas industry and biogas • The German gas industry is, in cooperation with agriculture, committed to create a competitive biogas market. This is also expressed in the declaration of commitment issued by the BGW, the German Association of the German gas and water industries, on 24 August 2007. • The objectives set by the politicians are: • the share of renewables in energy supply of new private homes shall be 20 %; • the dependency from natural gas imports shall decrease; • the emission of greenhouse gases shall be significantly reduced; • the development of energy production from renewables will create some 100.000 new jobs in the country.
Bio-natural gas market – Preliminary conclusion • Market predetermined by politics • Fast growth possible • Economical viable • Existing support systems improvable • Risk of political misguidance
Biogeneticprimary energy Conversion Secondary energy Final utilization of energy Examples: Wood chips Waste wood Chipping Heat production Mais Corn Biogas Power production Fertilization Manure PressingEsterization etc. Use asvehicle fuel Bio diesel (RME) Rape seed Biomass potential in Germany:systems Technical energy carrier potential Possible contribution of biomass to the supply of Energy
BGW/DVGW – study“Analysis and Evaluation of possibilities for utilization of biomass in Germany“ • In January 2006 a study initiated by the associations of the German gas and water industry BGW and DVGW was published. The steering committee comprised besides representatives of the gas industry also the German biogas association (Fachverband Biogas e.V.), the German farmers association (Deutscher Bauernverband), the federal German ministry for the environment, the federal German ministry for consumer protection and agriculture and the states ministries for agriculture and for the economy and energy of Bavaria. • The study was performed under conduct of the Wuppertal institute, split into work packages, by the institute for energetics (IE Leipzig), the Fraunhofer institute for the environment, safety and energy techniques (UMSICHT, Oberhausen) as well as the gas heat institute (Gaswärme-Institut GWI, Essen)