ecoinvent: methodological issues around lca ghg emissions - the swiss approach

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Niels Jungbluth ESU-services Ltd., Uster, Rainer Zah EMPA and ecoinvent Centre, St. Gallen Switzerland ecoinvent: Methodological issues around LCA GHG emissions - the Swiss approach Expert meeting LCA GHG methodologies for bioenergy: Beyond biofuels European Environment Agency, Copenhagen, 10 June 2008

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ecoinvent: Methodological issues around LCA GHG emissions - the Swiss approach. Expert meeting LCA GHG methodologies for bioenergy: Beyond biofuels European Environment Agency, Copenhagen, 10 June 2008. Status in Switzerland. Full LCA is basis for tax reduction for biofuels 40% GWP reduction - PowerPoint PPT Presentation

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Page 1: ecoinvent: Methodological issues around LCA GHG emissions - the Swiss approach

Niels JungbluthESU-services Ltd., Uster,

Rainer ZahEMPA and ecoinvent Centre, St. Gallen

Switzerland

ecoinvent: Methodological issues around LCA GHG emissions - the

Swiss approach

Expert meetingLCA GHG methodologies for bioenergy: Beyond biofuels

European Environment Agency, Copenhagen, 10 June 2008

Page 2: ecoinvent: Methodological issues around LCA GHG emissions - the Swiss approach

www.esu-services.chPage 2

Status in Switzerland

• Full LCA is basis for tax reduction for biofuels– 40% GWP reduction– <125% of overall environmental impacts (UBP)

than fossil reference– Cradle to grave LCA one prerequisite

• Data provision by importers or producers of biofuels not from waste

• Common background database and methodology: ecoinvent v2.0

Page 3: ecoinvent: Methodological issues around LCA GHG emissions - the Swiss approach

Harmonization of data collection in ecoinvent

• Collaboration of several research institutes and consultants

• Clear definition of product properties• Guidelines for methodology e.g. allocation,

land transformation• Standard assumptions, e.g. prices in

allocation, distances for biomass transports, regional storage

Page 4: ecoinvent: Methodological issues around LCA GHG emissions - the Swiss approach

Allocation: Example Biogas

use, digested matter(0.71 kg)

disposal, organic waste(1 kg)

biogas(0.1 Nm3)

biogas plant

organic waste, to biogas plant(1 kg)

cleaning, filling station

agriculture

Page 5: ecoinvent: Methodological issues around LCA GHG emissions - the Swiss approach

Allocation• Multi-output processes are stored in the database – BEFORE allocation• Input- and output-specific allocation factors, i.e.

individual allocation factor allowed per pollutant and input• Allocation executed after import of dataset into database

-> calculation of allocated unit processes-> matrix becomes invertible

• NO system expansion,NO creditsNO double counting of impacts

• All products included: fuel, electricity, heat, material, fertilizer, waste management, fodder, food, etc.

• Cut-off applied for outputs without economic value and wastes for recycling

Page 6: ecoinvent: Methodological issues around LCA GHG emissions - the Swiss approach

Land use change:Clear cutting of primary forests

• Agricultural area is increased by clear cutting• Land transformation leads to CO2 emissions from soil

and biomass• Burning of residues with further emissions• Loss of biodiversity• CO2 from land transformation accounts for about 90%

of Brazil CO2 emissions• Particles from residue burning are an important

problem in South-East Asia

Page 7: ecoinvent: Methodological issues around LCA GHG emissions - the Swiss approach

Principle of investigation• Increase in agricultural area for the production in the

reference year?• Emissions per m2 of clear cut land?• Allocation of emissions between wood production and

stubbed land• Stubbed land assumed the main driver• New elementary flow „CO2, land transformation“ as

used by IPCC for different possibilities of analysis • No indirect effects – double counting in a database!

Page 8: ecoinvent: Methodological issues around LCA GHG emissions - the Swiss approach

Plant oil production

0

0.5

1

1.5

2

2.5

3

3.5

4

4.5

rape oil CH rape oil RER palm oil MY palm kernel oilMY

soybean oil BR soybean oil US Soya oil RER

fossil, non-CO2 CH4, biogenic CO2

0

0.5

1

1.5

2

2.5

3

3.5

4

4.5

rape oil CH rape oil RER palm oil MY palm kernel oilMY

soybean oil BR soybean oil US Soya oil RER

fossil, non-CO2 CH4, biogenic CO2 CO2, land trans

kg CO2-eq per kg oil at plant

Page 9: ecoinvent: Methodological issues around LCA GHG emissions - the Swiss approach

Models for agricultural emissions

Indirect N2O emissions due to nitrate leaching are taken into account

Page 10: ecoinvent: Methodological issues around LCA GHG emissions - the Swiss approach

www.esu-services.chPage 10

Capital goods must be included

• Share in GWP up to 10-30%• Especially important in agriculture with low usage

intensity• Exclusion would give wrong picture• Article published in the Int.J.LCA that gives further

details and recommendationsFrischknecht R, Althaus H-J, Bauer C, Doka G, et al., The environmental

relevance of capital goods in life cycle assessments of products and services. Int. J. LCA, 2007. DOI: http://dx.doi.org/10.1065/lca2007.02.309.

Page 11: ecoinvent: Methodological issues around LCA GHG emissions - the Swiss approach

(Jungbluth et al. 2008: LCA of biomass-to-liquid fuels)

GWP reduction of BTL-Diesel

0 0.0002 0.0004 0.0006 0.0008 0.001

diesel

BTL

passenger car roadevaporation and tyre abrasion provision fuelcombustion, fuel

52%

65%

Neglecting parts of the life cycle leads to different conclusions concerning reduction potentials expressed as a percentage

Page 12: ecoinvent: Methodological issues around LCA GHG emissions - the Swiss approach

www.esu-services.chPage 12

UBP 06

0% 100% 200% 300% 400% 500%

Eco-indicator 99

0% 100% 200% 300% 400% 500%

GWP

0% 20% 40% 60% 80% 100% 120%

Methane manure, optimizedMethane manure+cosubstrate, optimized

100% Recycled plant oil ME FREthanol whey CH

100% Recycled plant oil ME CHMethanol fixed bed CH

Methane woodMethanol fluidized bed CH

Ethanol sugar cane BREthanol grass CHEthanol wood CH

Ethanol sweet sorghum CNEthanol sugar beets CHMethane sewage sludge

Methane grass biorefinery100% Soy ME US

Methane biowaste100% P almoil ME MY

100% Rape ME CHMethane manure+cosubstrate

Methane manure100% Rape ME RER

Ethanol corn USEthanol rye RER

Ethanol potatoes CH100% Soy ME BR

BTL-fuel, miscanthus, ICFB-DBTL-fuel, short-rotation wood, CFB-DBTL-fuel, short-rotation wood, ICFB-DBTL-fuel, short-rotation wood, cEF-D

BTL-fuel, forest wood, cEF-DBTL-fuel, straw, CFB-DBTL-fuel, straw, dEF-DBTL-fuel, straw, cEF-D

BTL-fuel, straw, CH, cEF-DNatural gas, EURO3

Diesel, low sulphur EURO3P etrol, low sulphur EURO3

Comparison of biofuels

Page 13: ecoinvent: Methodological issues around LCA GHG emissions - the Swiss approach

Conclusion from biofuels study

• A broad variety of investigated biofuels have a significant GWP-reducing potential

• Environmental impacts of biofuel pathways are more dependent on the raw material and its production, not on the type of product or conversion process

• Many biofuels from energy crops have higher overall impacts than fossil fuels

Page 14: ecoinvent: Methodological issues around LCA GHG emissions - the Swiss approach

Conclusions (2)• Differences of biomass production to be considered:

– Natural variation: sun, soil, water, climate– Agricultural technology: Fertilization, irrigation,

pesticides use, machinery use– Specific issues: land transformation, burning

• ecoinvent data provides the best basis for such assessments: transparent, harmonized, unit processes that can be reworked, numerous background data

Page 15: ecoinvent: Methodological issues around LCA GHG emissions - the Swiss approach

Niels JungbluthESU-services Ltd., Uster,

Rainer ZahEMPA and ecoinvent Centre, St. Gallen

Switzerland

Annexe

Page 16: ecoinvent: Methodological issues around LCA GHG emissions - the Swiss approach

Problem setting“Ökobilanz von Energieprodukten”

• Diverging results for bioenergy and biofuels in separate studies in 2004

• ecoinvent data v1.3 covered only a part of bioenergy chains. No common database

• Aims to fully investigate the most important bioenergy chains transparent and publically available

• Main issue biofuels in Switzerland or imported• Support for energy policy (fuel tax reductions)• Examination for GHG reduction potential• Investigation of several environmental aspects of “biofuels”

supply chains

Page 17: ecoinvent: Methodological issues around LCA GHG emissions - the Swiss approach

Possible classifications of fuels• Chemical classification of energy carrier

– methane, ethanol, methanol, hydrogen, oils, methyl ester, liquids (petrol, diesel), ETBE, MTBE

• Resources used– Non-renewable: crude oil, natural gas, coal, nuclear– Renewable: energy crops (edible, non-edible), algae, forest wood,

biomass residues, sun, wind• Type of conversion process

– mechanical, chemical reaction, thermal treatment, fermentation, anaerobic digestion, gasification, Fischer-Tropsch synthesis, biotechnical

• Marketing: – Sunfuel, Sundiesel, Ökodiesel, Biodiesel, Naturgas, 1st, 2nd, 3rd generation

Page 18: ecoinvent: Methodological issues around LCA GHG emissions - the Swiss approach

Resources, conversion techniques and “bioenergy” products investigated

biomass ressources (crops, wood, residues)

biogas

transport devices

wood pellets

heating

combined heat and power plant

electricity

methanolBTL-fuelshydrogen

synthetic gasethanol

filling station

plant oils

fatty acid methyl ester

wood chips

Page 19: ecoinvent: Methodological issues around LCA GHG emissions - the Swiss approach

Investigated biofuels

Methane 96%agriculturebiowastesludgewheygrasswood

Ethanol 99.7%woodgrasspotatoessugar beetswheysugar cane BRmaizerye DE / RER

Methanolwaste woodIndustrial wood

XMEWaste cooking oilRape seed CH/RERsoya oil US / BRpalm oil MY

BTLforest woodshort-rotation woodmiscanthusstraw

Page 20: ecoinvent: Methodological issues around LCA GHG emissions - the Swiss approach

Data contributions

ESU-services•Project organisation•Methodology•Clear cutting•Gas upgrading and distribution•Validation

Carbotech•Agriculture•Biogas

ETH•Biogas•Chemicals•Agriculture•Ethanol

Infras•Transports

PSI•Transports

Data basev1.3

Doka•Waste management

Eners / LASEN•Synthetic fuels•Plant oils•Methyl ethers (XME)•Ethanol

Chudacoff•Chemicals

Page 21: ecoinvent: Methodological issues around LCA GHG emissions - the Swiss approach

Raw data biogasName

Loca

tion

Uni

t biowaste, to anaerobic digestion

biogas, from biowaste, at

storage

disposal, biowaste, to anaerobic digestion

digested matter,

application in agriculture

Location 0 0 CH CH CH CH InfrastructureProcess 0 0 0 - - -

Unit 0 0 kg Nm3 kg kg biogas, from biowaste, at storage CH Nm3 1.00E-1 100.00 - - disposal, biowaste, to anaerobic digestion CH kg 1.00E+0 - 100.00 - digested matter, application in agriculture CH kg 7.12E-1 - - 100.00 heat, natural gas, at boiler condensing modulating >100kW RER MJ 5.94E-1 18.24 81.76 -

electricity, low voltage, at grid CH kWh 4.00E-2 18.24 81.76 - disposal, municipal solid waste, 22.9% water, to municipal incineration CH kg 1.00E-2 18.24 81.76 -

diesel, burned in building machine GLO MJ 1.80E-2 - - 100.00 transport, lorry 16t CH tkm 1.50E-2 - 50.00 50.00 solid manure loading and spreading, by hydraulic loader and spreader CH kg 1.00E+0 - 50.00 50.00

Carbon dioxide, in air - kg 5.95E-1 55.00 - 45.00

Carbon dioxide, biogenic - kg 7.05E-1 18.26 81.79 0.05 - Methane, biogenic - kg 8.53E-3 18.24 81.76 -

Page 22: ecoinvent: Methodological issues around LCA GHG emissions - the Swiss approach

Inventory Clear CuttingName

Loca

tion

Infra

stru

ctu

reP

roce

ss

Uni

t clear-cutting, primary forest

round wood, primary forest, clear-cutting, at forest road

provision, stubbed

land

Location BR BR BRInfrastructureProcess 0 0 0

Unit ha m3 m2round wood, primary forest, clear-cutting, at forest road BR 0 m3 5.21E+1 100 -

provision, stubbed land BR 0 m2 1.00E+4 - 100 Wood, primary forest, standing - - m3 1.82E+2 29 71 Transformation, from tropical rain forest - - m2 1.00E+4 - 100 Transformation, to forest, intensive, clear-cutting

- - m2 1.00E+4 - 100

power sawing, without catalytic converter RER 0 h 1.24E+1 100 - Carbon dioxide, land transformation - - kg 1.20E+5 - 100 Carbon monoxide, fossil - - kg 7.84E+3 - 100 Methane, fossil - - kg 5.14E+2 - 100

Page 23: ecoinvent: Methodological issues around LCA GHG emissions - the Swiss approach

Inventory agricultural product

Name

Loca

tion Uni

t soybeans, at farm

Location BRInfrastructureProcess 0

Unit kgOccupation, arable, non-irrigated m2a 1.97E+0Transformation, to arable, non-irrigated m2 3.93E+0Transformation, from forest, intensive, clear-cutting m2 6.22E-2Transformation, from arable, non-irrigated m2 3.77E+0Transformation, from shrub land, sclerophyllous m2 1.03E-1provision, stubbed land BR m2 6.22E-2

Page 24: ecoinvent: Methodological issues around LCA GHG emissions - the Swiss approach

www.esu-services.chPage 24

Share capital goods(starting point, MJ fuel)

0%

20%

40%

60%

MJ-Eq kg Sb eq kg CO2 eq kg C2H4 kg SO2 eq kg PO4--- eq m3 m2a

cumulativeenergy demand

abioticdepletion

global warming(GWP100)

photochemicaloxidation, non-

b

acidification eutrophication water use landcompetition

BTL-fuel, miscanthus TUV BTL-fuel, straw CUTECBTL-fuel, straw FZK BTL-fuel, straw UETBTL-fuel, wood CUTEC BTL-fuel, wood TUVBTL-fuel, wood UET dimethylether, black liquor Chemrec

Page 25: ecoinvent: Methodological issues around LCA GHG emissions - the Swiss approach

Questions to be answered

• Using BTL reduces the GWP by X% compared to fossil fuel

• Using a specific amount (e.g. 1 MJ or 1 kg) of BTL reduces the GWP by Y kg (or another appropriate unit) compared to fossil fuel

Page 26: ecoinvent: Methodological issues around LCA GHG emissions - the Swiss approach

www.esu-services.chPage 26

Calculations of potential reduction

100%

38%

20%

15%

12%

Page 27: ecoinvent: Methodological issues around LCA GHG emissions - the Swiss approach

And again: How much better are biofuels?

• If we want an answer like „the use of biofuel has ???% lower GWP than fossil fuels“ than we have to include the all parts of the life cycle, e.g. for transports also cars and streets

• Neglecting certain parts of the life cycle, even if the same for both options, will bias the results

• System boundaries must be stated correctly if comparing reduction figures, e.g. well-to-wheel should include the wheel

• See www.esu-services.ch/btl/ for background paper

Page 28: ecoinvent: Methodological issues around LCA GHG emissions - the Swiss approach

0 200 400 600 800 1000

UBP [Pt/pkm]

Aggregated Environmental Impact

LCA of Biofuels: Main Results

-0.05 0.00 0.05 0.10 0.15 0.20 0.25

100% Rape ME CH

100% Rape ME RER

100% Palmoil ME MY

100% Soy ME US

100% Soy ME BR

100% Recycled plant oil ME CH

100% Recycled plant oil ME FR

Methanol fixed bed CH

Methanol fluidized bed CH

Ethanol grass CH

Ethanol potatoes CH

Ethanol sugar beets CH

Ethanol whey CH

Ethanol wood CH

Ethanol sweet sorghum CN

Ethanol rye RER

Ethanol corn US

Ethanol sugar cane BR

Methane grass biorefinery

Methane manure

Methane manure+cosubstrate

Methane manure, optimized

Methane manure+cosubstrate, optimized

Methane biowaste

Methane sewage sludge

Methane wood

Diesel, low sulphur EURO3

Petrol, low sulphur EURO3

Natural gas, EURO3

CO2-eq. [kg/pkm]

Cultivation

Production

Transport

Operation

Bio

dies

elEt

hano

lM

etha

neFo

ssil

GHG emissions

fossil benchmark

Page 29: ecoinvent: Methodological issues around LCA GHG emissions - the Swiss approach

Mileage per hectare

short-rotation wood, cEF-Dshort-rotation wood, CFB-D

miscanthus, ICFB-D

short-rotation wood, ICFB-Dforest wood, cEF-D

Page 30: ecoinvent: Methodological issues around LCA GHG emissions - the Swiss approach

Outlook

• Full LCA based on investigated data published in the framework of the project (http://www.esu-services.ch/bioenergy.htm)

• Life cycle inventories of BTL-fuels are published in EcoSpold format in a European project (www.esu-services.ch/renew.htm)

• Ongoing discussion on guidelines for tax exemption will further increase the need for reliable LCI data

• Shift of focus from fuel to fuel consumption