The double benefit of biogas

Transcription

1 Christian Ege, director The double benefit of biogas Dalian, 28 April 2011 The Danish Ecological Council

2 Photo: Copyright Lemvigbiogas.com >Titel< I Christian Ege, formand

3 Renewable energy in Denmark PJ '81 '82 '83 '84 '85 '86 '87 '88 '89 '90 '91 '92 '93 '94 '95 Wind Straw Wood Biogas Biodegradable waste Heat pumps etc '96 '97 '98 '99 '00 '01 '02 '03 '04 '05 '06 '07 '08 Danish Biogas Association

4 Biogas - in principle Sustainable agricultural production, food supply and export Manure Digested biomass Danish Biogas Association Biogas Plant Redistribution and improved utilisation of nutrients Protection of aquatic environment, less smell Recovery of nutrients and energy content Organic waste Renewable energy Energy supply security Combined power and heat Transportation?

5 Biogas from residues or crops If biogas is made from organic residues, you get a double benefit: -Reduced emission of methane and laughter gas -Substitution of fossil fuels -Reduction of C0 2 -eq. can be more than 100% -If you grow crops, like maise, dedicated for biogas the climate advantage is less, like 1st generation biofuels

6 Advantages of biogas plants Greenhouse gas reduction Efficient kg CO2eq per ton biomass heat and power: 220 % transportation: 167 % CO2 eq Fossil fuel substitution N2O Methane Danish Biogas Association

7 Advantages of biogas plants Greenhouse gas reduction Utilisation of organic waste Redistribution of manure Organic fertiliser Smell from slurry reduced Improved nitrogen utilisation Reduced risk of leaching Utilisation of Nitrogen in winter wheat 0 Cattle slurry Pig slurrydigested slurry Liquid fraction Danish Biogas Association

8 Biogas -stable and flexible Biogas plant Gas production Continous, stable and predictable Up/down regulation through seasons Gas utilisation Adaptation to demand Storage on biogas plant Injection into gas grid Stabilisation of energy system with increased share of windpower Danish Biogas Association

9 Other advantages Biogas can be combined with windpower Biogas can be stored hours with affordable costs Reduces particle pollution compared to coal or diesel Reduces noise from vehicles Christian Ege

10 Societal advantages Greenhouse gas reduction Protection of aquatic environment Rural life quality (smell) Pathogen reduction Energy security Optimal biomass utilisation Danish Biogas Association

11 Payment for electricity from biogas Danish Biogas Association

12 Biogas production and potential pct. of total energy cons % of natural gas % of transportation PJ Landfill gas Garden waste Household/food waste Meat and bone meal Industrial waste import Industrial waste Danish Sewage sludge Manure Potential Danish Biogas Association Kilde: Energistyrelsen

13 Danish biogas plants Number of plants l 22 centralised biogas plants l 60 farm scale biogas plants l l Biomass in biogas plants Manure 2 mill. t Organic residues 0.5 mill. ton Total 2.5 mill. ton Danish Biogas Association

14 Biogas from manure cogeneration - GHG reduction Methane from stock Laughter gas from stock Kg CO 2 -eq/t Kg CO 2 -eq/t manure (pigs) manure (cows) N 2 O f. spreading Methane f. -4,8-5.4 motor Subst. of nat.gas N 2 O f. leakage C-storage in soil Total Christian Ege

15 CO 2 -emissions (CO 2 -equiv.) Cowi for DEA 2006, g/km 2025, g/km Diesel Gasoline Bioethanol, 1. generation Bioethanol, 2. generation ? 60 Bio diesel/ RME Natural gas Electric cars 131 (?) 110 (?) Hydrogen 251 (?) 228 (?) Biogas Christian Ege

16 Social economic costs, DKK/km Diesel Gasoline Bioethanol, 1.generation Bioethanol, 2. generation ? Bio diesel/ RME Natural gas Electric Hydrogen Biogas Christian Ege

17 Which organic residues? - Manure more solid matter must be added - sewage cleaning sludge - biogas production can be combined with spreading of sludge on farm land requires strong chemicals policy, to avoid pollutants - canteen and restaurant waste: requires high quality separation (no plastic etc.) - organic house hold waste: requires high quality separation Christian Ege,

18 Which organic residues? - Renescience : concept for production of liquid organic material on the basis of nonseparated household waste using enzymes (Novozymes) high content of solid matter low pollution -grass from nature areas grass cutting is good for biodiversity Christian Ege

19 Manure For large scale biogas plants you need high density of animals transportation costs are high Denmark: 1-2 animal (livestock) units (AU) per hectare 1 animal unit is manure with 100 kg N app. 1 cow or 4 sows (mother pigs), or 35 fatteners (pigs for slaughtering) or app. 3,000 chickens (for slaughtering) EU nitrate directive allows 1.7 animal units per hectare. Denmark has got a dispensation for cows, up to 2.3 AU/hectare. Pigs: 1.4 AU per hectare Christian Ege

20 Manure separation Biogas plants can be combined with separation of manure before or after the biogas plant This can solve if you have lack of hectares the thin fraction can be spread near the farm The thick fraction can be transported more distant Most of the phosphorous (P) is in the thick fraction Too much P in much arable land in Denmark Christian Ege

21 Biogas used for Heat and power production gives the highest CO 2 -reduction if there is a heating demand and pipes near the biogas plant Transport improves independence of oil - Electricity best for small (person) cars - Gas, especially for heavy vehicles Heavy vehicles can do with few filling stations for gas Political decision: use in transport sector must be treated equal to use for cogeneration Christian Ege

22 Upgrading and transport Upgrading (removal of CO 2 etc.): necessary for transport via natural gas net and for use in transport sector Denmark has a widespread net of pipes for natural gas First Danish upgrading plant will open this summer To create a financial incentive higher price for biogas than natural gas you need a certificate system. Need for tax relief for biogas for transport Christian Ege

23 Project on biogas for heavy vehicles Two projects are about to start for trucks and busses Has been used in Sweden for some years based on sewage sludge and house hold waste. 100 filing stations for biogas In Denmark: based on manure Grant from the government. More expensive to buy truck or bus for biogas/natural gas. Christian Ege

24 Project on biogas for heavy vehicles Busses: Liquid biogas (-160 o C), imported on trucks from Sweden Trucks: pressurised biogas/natural gas sold via certificate system. Dual fuel: app. 70% gas, and gas engine (100%gas, but less efficient) longer term: liquid for long distance transport (lower volume). Measuring of emissions Christian Ege

25 End Thank you for your attention! Christian Ege