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This presentation shows the outcome of the SUSTAINGAS “Report on analysis of sustainability performance of organic biogas plants”. It was prepared by Frank Hofmann, Consultant Bioenergy at Ecofys. The analysed categories were greenhouse gas balance, sustainability issues of different substrates, farmland fertility, food vs fuel, biodiversity, water quality, fossil energy free farms and socio economic aspects. The report “development of recommendations and strategies to stakeholders” is available on the website: http://www.sustaingas.eu
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Sustainability of Biogas Plants in Organic Farming
SUSTAINGAS Workshop, Austria
Frank Hofmann Ecofys Germany GmbH
Sustainability of Biogas Plants in Organic Farming
Sustainability criteria
Life Cycle Assessment for 12 model biogas plants
Further Sustainability aspects Soil quality
Food vs Feed
Water quality
Biodiversity
Independence from fossile energy
Socioeconomic effects
Sustainability Criteria
RED: Biomass for utilization as fuel and bioliquids are subject to sustainability criteria
Less GHG-effects to fossil fuel reference
Land use requirements must not have negative impacts to biodiversity or carbon stocks
Sustainable agricultural practice
Introduction of sustainability criteria for biomass and biogas is under discussion, at EU-level
Organic biogas can be produced sustainably
Sustainability Criteria
Sustainability is mainly influenced through the use of input material
GHG
Balance
Envir.
Aspects
Social
AspectsLUC
Biodiv.
ILUC + Food
competition
Food industry
and municipal
residues
Catch crops
Animal
excrements
Existing agricultural
land
Idle and marginal
land
Cascading &
Recycling
Energy crops
Feedstock Sustainability issues
Harvesting
residues
© ECOFYS
LCA/ GHG-Emission Accounting
Definition of 12 biogas plant models
LCA Methodology Calculation according to „typical German“ Methodologies
Calculation corresponding to RED and COM(2010)11
SUSTAINGAS GHG-tool based on BioGrace tool (www.biograce.net)
Adaptations in the SUSTAINGAS calculation to RED/COM Methodology:
GHG emissions are attributed to electricity. Emission reductions from substituting fossil based heat are included as credit.
GHG-emission savings conneted to manure treatment are quantified
Additional Information: Impacts of plant production to humus content
LCA Impact Parameter
Biomass cultivation (Pesticides, fertilizer, diesel consumption)
Transport
Running of plant, diffuse emissions
Utilization of biogas, CHP
Impacts to Manure efficiency
Humus content
Result: LCA I
Overview of 12 biogas plant models
-1,300
-1,100
-900
-700
-500
-300
-100
100
300
500
700
900
g C
O2
,eq/k
Wh
el
Fossil comparator
Cultivation
Transport and distribution (including storage ofraw material)
Diffuse emissions
Methane leakage in the CHP generator
Externally used heat
Avoiding methane emissions from manure
Net emissions
Key findings, GHG
Avoided methane emissions due to manure treatment as most relevent effect
Substitution of fossil heat second most influencing factor
Biogas process is dominated by diffuse methane emissions; based on CHP operation
The cultivation of energy crops is connected to emissions
The more energy crops are used the higher CO2 emissions exist
The difference between biogas plants in organic and conventional farms is determined highly through use of substrates
Emissions associated with transport are of minor importance
Scenario: Methane emissions
15 % diffuse Methane emissions (before 1 %)
Energy crops are located around the fossile comparator!
Manure treatment plants mitigate GHG
-1300
-1100
-900
-700
-500
-300
-100
100
300
500
700
900
1100
g C
O2
,eq/k
Wh
el
Fossil comparator
Cultivation
Transport and distribution (including storage ofraw material)
Diffuse emissions and storage
Methane leakage in the CHP generator
Externally used heat
Avoiding methane emissions from manure
Net emissions
Further environmental aspects
Two comparisons of operation methods are analysed: Organic Farms with and without a biogas plant
Biogas plants in organic and conventional farming
Generalization: Whole Europe
Individual situations are crucial (climate, soil quality, crop rotation, regime) => Generalization critical
Soil quality It has to be distinguished between crop cultivation and effect of digestate.
Impacts of a biogas plant onto organic farm Differences in farms with and without livestock
Catch crops are cultivated more often
Increased N fixation, less N-leaching (in comparison to mulching), reduction of N2O-emissions
Flexible utilization of fertilizer
Humus balance, individual reconsideration, C-removal vs root growth
Phytosanitary effects; Deaktivation of weed seeds, promotion of N-availability
The influence onto soil quality is dominated through substrates and their cultivation .
Biogas in organic in comparison to conventional farming More catch crops, less renewable resources
Pesticides, mineral fertilizer
Food vs Feed
Effects of biogas on food security in organic farming depends on the substrates and the use of the land associated with it:
Substrate Positive Effects Negative Effects
Enery crops Area competition Soil quality
Catch crops Increased yield Higher protein content in plants
Livestock production: competition
Harvesting residues
Increased yield Higher protein content in plants
Livestock production: competition
Manure Increased yield Higher protein content in plants
Water quality
Organic farm with and without Biogas plant Catch crops, decreased N-leaching in comparison to mulching
Manure, N-leaching can be increased; Dung, N-leaching reduced
Disasters have high negative potential
Organic vs conventional farm Correlation of regions with high density of animal husbandry, density of biogas and pollution of ground water with Nitrate
Intensification of conventional farms can additionally lead to higher N-loads
N often is a limiting factor vs higher N-inputs
Biodiversity
Organic Farming
Correlation with Biodiversity With soil fertility, with N-charge (digestate)
Expension of cultivation and harvest period
Seeds of foreign kinds are deactivated
Negative impacts of over-fertilization, eutrophication
Erosion of Biomass (Manure, straw, harvest residues) has complex impacts
Losses of habitats
Yield increase
Better control (especially N)
Cultivation of energy crops Higher competition and pressure on agricultural areas
Reduction of closure sites
LUC
Impact onto biodiversity dependend on plant type
Independence of fossile energy
Biogas can be used in many ways Electricity
Heating and cooling
Heating of buildings
Processes (Breeding of piglets, cooling dairy products,….)
Drying
Selling
Fuels
As biomethan, as a substitute for natural gas
As biogas directly
Biogas can hence lead to a substitution and independence of fossile energy
Socioeconomic effects
Few differences btw organic and conventional biogas
General impacts of operating with biogas
Social effects Development of rural areas
Creating a network, exchange of information
Cooperation
Acceptance
Negative: Odor, transport, noise, fear
Employment opportunities 45.000 jobs in biogas sector (source: FVBG, Germany), 10.000 farms
App. 12 people per Mwel that is installed
Revenue Investment biomass electricity (solid & gaseous): 1,5 Mia € in 2012
Turnover biomass (Electricity and heat, without fuels): 6,8 Mia. € in 2012 (AGEEStat); (Biogas kanns: 6 Mia. €, German sources)
Regional turnovers increase
Summary I
GHG balance:
Biogas plants in organic farming can improve the LCA of a farm and further produce renewable energies
Manure treatement is a crucial part
Utilization of heat
Avoid methane emissions
Limit cultivation of energy crops
Summary II
Soil fertility can be improved through a biogas plant.
Production of organic biogas does not (or in a reduced way) mean a competition to food production
Water quality: Reduced N-leaching
Biodiversity: Biogas can expand crop rotation cycle
Biogas offers the possibility to become independent of fossile resources
Biogas is socio economically feasible Acceptance, (local) employment opportunities, revenues
Thank you for your attention!
Frank Hofmann Ecofys Germany GmbH [email protected]