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Using LCA to understand the climate change effects of bioenergy
Dr Miguel Brandão
Outline
• Life Cycle Assessment as a decision‐support tool
• Policy Context• Unresolved methodological issues in the LCA of bioenergy systems – Reference systems & carbon stocks– Biogenic carbon & time accounting– iLUC, modelling approaches & allocation
• Prospects
Counter‐intuitive lessons from hard systems analysis
•What’s better?
– Composting vs Incineration– Reusable nappies vs Disposable nappies– Recycled bags vs Plastic bags– Recycled paper vs Virgin paper– Organic food vs Conventional food– Local food vs Imported food– Bioenergy vs Fossil fuels
Food Miles
Greenhouse gas emissions from the food chain: 2004 in United Kingdom
Source: SEI (2006) in defra (2007)
Life Cycle Assessment compared with process or site-specific environmental analysis
Extraction and
processing of raw materials
Manufacture Use, reuse and/or
maintenance
Distribution and retailing
Waste management
Raw materials and energy
Product(s); solid waste; emissions to air, water and land
ENVIRONMENT
Source: Hodgson et al. (1997) in Cowell (1998).
Environm
entalmechanism
(impact pathw
ay)
Environm
entalmechanism
(impact pathw
ay)
Midpoints
NOx, Cd, CO2, CH4, dioxins, energy, coal, silver ore, land use… and other emissions and resource flows... Inventory
Summer sm
og
Ozone
layer
Acidificatio
n
Clim
ate change
Carcinogen
s
Land
‐use
Ecotoxicity
Eutrop
hicatio
n
Resource dep
letio
n
Respira
tory inorganics
Radiation
HumanHealth
Naturalenvironment
Natural resources
Area of Protection
Toxicity
weighting
Single indicator (overall environmental impact )
weighting
Aggregation to single score indicator
· Integrated Product Policy Communication (IPP), 2003:
“LCA is the best framework for assessing the potential environmental impacts of products, but the debate is ongoing about good practice”
· Sustainable Consumption and Production Action Plan, 2008:
“To implement this policy, consistent and reliable data and methods are required to asses the overall environmental performance of products …”
European Commission response to the need for consistent and quality‐assured life cycle data and assessments
European Platform on Life Cycle Assessment
Policy Context: EC policy needs
Necessity of Life Cycle Thinking in Policy and Business· Avoid shifting of burdens:
∙ from one stage to another ∙ among countries∙ across different environmental and health impacts and resources use∙ from one generation to the next
· Fair basis for comparisons:∙ scope of assessments (stages, impacts, …)∙ same functionality
EU Renewable Energies Directive Implementation of Directive 2009/28/EC on the Promotion of the use of energy from renewable sources 10% share of biofuels in transports by 2020
The Directive addresses the production and use of biofuel in a sustainable context (Article 17): Minimum GHG savings, relative to fossil fuels of 35% (50% from 2017) Preservation of biodiversity on land used for biofuel production Preservation of lands with high carbon stocks Requirement for good agricultural and environmental conditions
• ILUC effect refers to the GHG emissions from land‐use conversions arising as a consequence of increased demand for land‐based products
Life cycle methodology –RED’s Annex V
04/03/2015 IEA Bioenergy Task 38 Webinar ‐ The Application of Life Cycle Assessment in quantifying the climate change effects of bioenergy
Typical and default values for biofuels
Biofuel production pathway Typical greenhouse gas emission saving
Default greenhouse gas emission saving
sugar beet ethanol 61 % 52 %
wheat ethanol 32 % 16 %
corn (maize) ethanol 56 % 49 %
sugar cane ethanol 71 % 71 %
rape seed biodiesel 45 % 38 %
sunflower biodiesel 58 % 51 %
soybean biodiesel 40 % 31 %
palm oil biodiesel 36 % 19 %
pure vegetable oil from rape seed 58 % 57 %
European Commission Renewable Energies Directive (2009)
Large variability in published GHG emissions
-1000
-500
0
500
1000
1500
2000
Ded
icat
ed F
eeds
tock
s
Res
idue
s
With
Avo
ided
Em
issi
on C
redi
ts
Pho
tovo
ltaic
s
Con
cent
ratin
g So
lar P
ower
Geo
ther
mal
Hyd
ropo
wer
Oce
an E
nerg
y
Win
d
Nuc
lear
Nat
ural
Gas
Oil
Coa
l
Life
Cyc
le G
reen
hous
e G
as E
mis
sion
s (g
CO
2e /
kWh)
Biopower (no LUC)
Count of Estimates 105 96 8 124 42 6 28 10 126 120 82 24 169 Count of References 29 30 6 26 16 5 11 5 49 31 35 10 49
Technologies powered by renewable resources
Technologies powered by non-renewable resources
Source: Heath et al. (2010) Special Session on Meta-Analysis of Energy LCAs. InLCA X
Applying LCA in quantifying the climate effects of bioenergy systems• Urgent need for replacing fossil fuels in order to mitigate climate change
• Bioenergy systems promising strategy• Quantified benefits of bioenergy systems very variable and depend on methodological choices – Reference systems & carbon stocks– Biogenic carbon & time accounting– iLUC, modelling approaches & allocation
• How important are these choices?
Reference Systems & Carbon Stocks
Carbon stocks in UK
Source: : Azeez (2009), IPCC (2003; 2006)
101 10166 77 82 101
21 0
90
5 2
0
50
100
150
200
250
Forest
Grasslan
dAnn
ual C
ropland
Organic
Cropland
Set-Asid
ePere
nnial
Cropla
nd
t C / ha
Above-Ground BiomassDead Organic MatterSoils
Change in carbon stocks(20 years after conversion)
Source: IPCC (2003; 2006)
Biogenic Carbon & Time Accounting
Radiative forcing (W/m2), t CO2‐eq. and t C*yr
Global Warming Potential: the extended Moura‐Costa approach
Global Warming Potential (CO2-eq)
20 years 100 years 500 years
Carbon Dioxide 1 1 1
Methane 72 25 7.6
Nitrous Oxide 289 298 153
Carbon Dioxide Sequestration (tonne-years)
1/14.6 = 0.074 1/47.8 = 0.021 1/157.3 = 0.006
Carbon tonne-years
0.074*44/12==0.27
0.021*44/12==0.08
0.006*44/12= =0.022
Calculating impacts from LU and (i)LUC
2/20*)( finini ECSECS
ECSini
Timetfin
EcosystemCarbon
Stock
tini
ECSfin
ECSdeficitECS inifinfinini ttECSECS
tini+20tini+1
Lashof Approach
Indirect Land Use Change (iLUC)
What is iLUC?dLUC vs iLUC
Crop displacement (Edwards et al. 2010)
Source: Edwards (2009)
Critical issues in iLUC modelling
1. GHG emissions from LUC– Land requirements– Reference system
2. Ascribing LUC to their drivers– Amortisation
3. Dealing with modelling uncertainties– Treatment of by‐products– intensification vs. expansion vs. displacement
Where does increased supply come from?• Existing agricultural land
1. Displacement decreased food availability or iLUC
2. Yield increases increased input use
• Newly‐converted agricultural land3. Direct Land Use Change
– Increased carbon emissions
Alternative modelling approaches
Economic‐equilibrium models
• Price elasticities
• Black boxes
Biophysical models
• Usually no constraints considered, full price elasticities
• Transparent physical relations
Comparison of iLUC models
31
Schmidt J H and Brandão M (2013), LCA screening of biofuels ‐ iLUC, biomass manipulation and soil carbon. Concito, Copenhagen
iLUC factors from different modelsSource iLUC Factor (g CO2‐eq./MJ)
Searchinger et al., 2008 106
Audsley et al., 2010 1.43 t CO2‐eq./ha of agricultural land used
Cederberg et al., 2011 n/a
EPA RFS2 30.1
Dumortier et al., 2009 118
Tyner et al., 2010 13.9
JRC 36
JRC ethanol 4 to 20
JRC biodiesel 36 to 60
Are models suitable for determining ILUC factors?
Source: Berndes, G., Bird, N. & Cowie, A., 2011. Bioenergy, land use change and climate change mitigation. Background Technical Report, Paris: International Energy Agency (IEA).
New EU proposal (October 2012) to reduce iLUC risk• Amends both the Renewable Energy (2009/28/EC) and Fuel
Quality (2009/30/EC) Directives• Avoids incentives for the continued displacement of food
crops for fuel– A 60% GHG‐saving for new biofuels installations (from 1 July 2014)– Including iLUC factors in the reporting by suppliers and MS– A 5% cap on the amount of biofuels in the EU’s 2020 transport mix– An end to public subsidies for 1st generation biofuels after 2020 unless
they can demonstrate “substantial GHG savings”– Incentives for 2nd and 3rd generation biofuels– A review of policy and scientific evidence on ILUC (in 2017)
04/03/2015 IEA Bioenergy Task 38 Webinar ‐ The Application of Life Cycle Assessment in quantifying the climate change effects of bioenergy
When the new ILUC proposal was launched on 17 October 2012, EU Climate
Commissioner Connie Hedegaard said that some biofuels currently receiving EU
subsidies were “as bad as, or even worse than the fossil fuels that they replace.”
Legislative milestones• 2008: EP asked EC to look into iLUC• 2010: importance of iLUC recognised but doubts about appropriate
methodology• October 2012: proposal for considering iLUC with factors for
different crop groups and a 5% cap• June 2014: EU Council reaches agreement:
– No subsidies for worst offenders post 2020– 7% cap from 1st generation biofuels– 0.5% target for advanced biofuels
• February 2015: Approved by EP Environment Committee (374 proposed amendments on iLUC!)– 6% cap– Boost advanced biofuels (1.25%)– Reduce iLUC (EU biofuels policy budget of €10 billion / year)
Estimated indirect land‐use change emissions from biofuels• Cereals and other starch rich crops ‐ 12 g CO2‐eq/MJ• Sugars ‐ 13 g CO2‐eq/MJ• Oil crops ‐ 55 g CO2‐eq/MJ
• Fossil fuel comparator ‐ 83.8 g CO2‐eq/MJ (2008)– 2012: 89.2 for diesel– 2012: 90.7 for gasoline– 2012: 90.3 for weighted average (3:1)
New factors for biofuels • Palm Oil – 105 g CO2‐eq./MJ• Soybean – 103 g CO2‐eq./MJ• Rapeseed – 95 g CO2‐eq./MJ• Sunflower – 86 g CO2‐eq./MJ• Palm Oil with methane capture – 83 g CO2‐eq./MJ• Wheat (process fuel not specified) – 64 g CO2‐eq./MJ• Wheat (as process fuel natural gas used in CHP) – 47 g CO2‐eq./MJ• Corn (Maize) – 43 g CO2‐eq./MJ• Sugar Cane – 36 g CO2‐eq./MJ• Sugar Beet – 34 g CO2‐eq./MJ• Wheat (straw as process fuel in CHP plants) – 35 g CO2‐eq./MJ• 2G Ethanol (land‐using) – 32 g CO2‐eq./MJ• 2G Biodiesel (land‐using) – 21 g CO2‐eq./MJ• 2G Ethanol (non‐land using) – 9 g CO2‐eq./MJ• 2G Biodiesel (non‐land using) – 9 g CO2‐eq./MJ
No GHG saving!
<35% GHG saving
50-60% GHG saving
35‐50% GHG saving
>60%
Modelling Approaches and Allocation
Attributional and consequential modelling
• UNEP/SETAC (2011). Shonan LCA database guidance principles:– Attributional approach: System modelling approach in which
inputs and outputs are attributed to the functional unit of a product system by linking and/or partitioning the unit processes of the system according to a normative rule.
– Consequential approach: System modelling approach in which activities in a product system are linked so that activities are included in the product system to the extent that they are expected to change as a consequence of a change in demand for the functional unit.
Consequential
Attributional and consequential modelling (Weidema, 2003)
Attributional
42
System boundary ‐ Dairy cow example
System boundary for substitution
System boundary for substitution and allocation
ISO/CLCA(substitution)
Allocation– impossible activities are created
Milk Meat Milk Meat
Allocation
Unallocated milking cow(per 100kg DM feed)
9.3kg Milk 2.2kg Meat
100kg DM feed
2.0kg CH4
28.3kg C in CO2
23.2kg Manure
35.0kg respiratory water
Milk: 77% of economic turnoverMeat: 23% of economic turnover
outputs = 100kg
04/03/2015 IEA Bioenergy Task 38 Webinar ‐ The Application of Life Cycle Assessment in quantifying the climate change effects of bioenergy
“Meat” and “Milk” from the multi‐output system “Dairy cow”
Original systems System expansion Dry matter allocation Economic allocation
Dairy cow Meat cattleMilk =
Dairy Cow‐Meat cattle
Meat = Meat cattle Milk 81% Meat 19% Milk 77% Meat 23%
Feed DM 100.0 26.0 74.0 26.0 81.0 19.0 77.0 23.0
Milk DM ‐9.3 ‐9.3 ‐9.3 ‐9.3
Meat DM ‐2.2 ‐2.2 ‐2.2 ‐2.2 ‐2.2
CH4 ‐2.0 ‐0.5 ‐1.5 ‐0.5 ‐1.6 ‐0.4 ‐1.5 ‐0.5
Manure DM ‐23.2 ‐4.7 ‐18.5 ‐4.7 ‐18.8 ‐4.4 ‐17.9 ‐5.3
C in CO2 ‐28.3 ‐8.1 ‐20.2 ‐8.1 ‐22.9 ‐5.4 ‐21.8 ‐6.5
Respiratory water ‐35.0 ‐10.5 ‐24.5 ‐10.5 ‐28.4 ‐6.6 ‐27.0 ‐8.1
Mass balance: 0.0 0.0 0.0 0.0 0.0 0.0 ‐0.4 0.4
Feed C 46.5 12.0 34.5 12.0 37.66 8.84 35.8 10.7
Milk C ‐5.3 ‐5.3 ‐5.3 ‐5.3
Meat C ‐1.0 ‐1.0 ‐1.0 ‐1.0 ‐1.0
CH4‐C ‐1.5 ‐0.4 ‐1.1 ‐0.4 ‐1.22 ‐0.29 ‐1.2 ‐0.3
Manure C ‐10.4 ‐2.2 ‐8.2 ‐2.2 ‐8.42 ‐1.98 ‐8.0 ‐2.4
C in CO2 ‐28.3 ‐8.4 ‐19.9 ‐8.4 ‐22.92 ‐5.38 ‐21.8 ‐6.5
C balance: 0.0 0.0 0.0 0.0 ‐0.2 0.2 ‐0.5 0.5
Allocated milking cow(economic allocation: milk 77%)
48
9.3kg Milk 2.2 Meat
77kg DM feed
1.5kg CH4
21.8kg C in CO2
17.9kg Manure
27.0kg respiratory water
outputs = 77.5kg
Milk: 77% of economic turnoverMeat: 23% of economic turnover
The co‐product algorithmCase study: Small additional demand for protein feed
Soybean mill
Barley to
generic feed
market
Market for generic vegetable
oil
Soybean production
Land Use
Palm oil mill Soybean
meal to generic feed
market
1 kg
Market for
protein feed, crude
1 kg
20.5 MJ energy feed
-20.5 MJ
-0.26 kg crude protein
Barley production
2.13 kg meal
0.53 kg veg. oil
‐0.53 kg veg. oil
‐2.77 kg barley
‐0.55 kg
Oil palm production
‐4. 9 kg FFB
2.77 kg soybean
To compare: An attributional system
Case study: Small additional demand for protein feed
Soybean meal to generic feed
market
Market for
protein feed, crude
Barley to
generic feed
marketprotein
Palm oil millmeal
Corn productionproteinRape oil
mill
Sunflower oil mill
meal
meal
Wheat flour millbran & germ
Rape production
Oil palm production
Soybean productionSunflower
production
Wheat production
Barley production
Land Use
Results for 1 kg soybean meal[kg CO2‐equivalents]Activity: Consequential AttributionalTotal of all activities -0.101 0.889iLUC 3.980 0.338Soybean cultivation 0.275 0.139Natural gas 0.082 0.042Light fuel oil 0.042 0.033Electricity BR 0.025 0.008Other chemicals -0.004 0.013Lorry -0.016 0.001Farm capital equipment -0.038 0.078Farm services -0.045 0.092Oil mill -0.658 0.014Diesel -0.675 0.107Oil palm cultivation -0.897 <0.001Barley cultivation -0.985 <0.001Fertiliser -1.130 0.002Other activities -0.057 0.021
04/03/2015 IEA Bioenergy Task 38 Webinar ‐ The Application of Life Cycle Assessment in quantifying the climate change effects of bioenergy
Case Study
UK bioenergy Crops Substitution effects Marginal producers
-Ethanol
-Biodiesel
-Combined Heat andPower
WheatSugar Beet
Oilseed rape
MiscanthusWillow SRCScots Pine
Gasoline + Animal feed*(DDGS)
Diesel + Animal feed* (rapecake)
Coal and/or Natural Gas(marginal feedstocks)
Argentina (soymeal),Indonesia (vegetable oil)and Canada (wheat)
*A combination of palm oil, soymeal and feedwheat (and associated land use!)
Bioenergy on Current Cropland in UK
‐12 000
‐10 000
‐8 000
‐6 000
‐4 000
‐2 000
0
2 000
4 000
6 000
8 000
FtFuelW FtFuelOSR FtFuelSB
kgCO2‐eq./ha
UK ‐ Fossil
UK ‐ Biogenic
Substitution ‐ Food
iLUC ‐ Food
Substitution ‐ Feed and vegetable oil
iLUC ‐ Feed and vegetable oil
Substitution ‐ Fossil Fuels
Bioenergy on Set Aside in UK
‐20 000
‐15 000
‐10 000
‐5 000
0
5 000
10 000
15 000
UK ‐ Fossil
UK ‐ Biogenic
Substitution ‐ Food
iLUC ‐ Food
Substitution ‐ Feed and vegetable oil
iLUC ‐ Feed and vegetable oil
Substitution ‐ Fossil Fuels
kgCO2‐eq./ha
Bioenergy on Grassland in UKkgCO2‐eq./ha
‐20 000
‐15 000
‐10 000
‐5 000
0
5 000
10 000
15 000
UK ‐ Fossil
UK ‐ Biogenic
Substitution ‐ Food
iLUC ‐ Food
Substitution ‐ Feed and vegetable oil
iLUC ‐ Feed and vegetable oil
Substitution ‐ Fossil Fuels
Critical parameters1. Reference System & Carbon Stocks
– Grassland 2,000‐7,000 kg CO2‐eq/ha higher than Set Aside– Carbon emissions from LUC (UK): 3 – 145 t C/ha
2. Biogenic carbon & Time accounting– Extended Moura‐Costa– Alternatives possible (Lashof, BioGWP)
3. Indirect Land Use Change, Modelling approaches & Allocation– European Commission factors:
• Cereals and other starch rich crops ‐ 12 g CO2‐eq./MJ• Sugars ‐ 13 g CO2‐eq/MJ• Oil crops ‐ 55 g CO2‐eq/MJ
– Attributional vs Consequential• Audsley et al. (2010): 1.43 t CO2/ha• CLCA: 1.32 t CO2‐eq./ha*year‐eq.• ALCA: 32 kg CO2‐eq./ha*year‐eq.
Schmidt, J.H., Weidema, B.P., Brandão, M., 2015. A Framework for Modelling Indirect Land Use Changes in Life Cycle Assessment. J. Clean. Prod. (accepted for publication)
Precision vs. Accuracy
High PrecisionLow AccuracyBiased results
High AccuracyLow PrecisionRepresentative Results
Source: Brandão et al. (2014) The Use of Life Cycle Assessment in the Support of Robust (Climate) Policy Making. Journal of Industrial Ecology
¨It is much more important to be able to survey the set of possible systems approximately than to examine the wrong system exactly. It is better to be approximately right than
precisely wrong.”
Tribus and El‐Sayed (1982)
Conclusions and Outlook• LCAs relevance for policy support growing
• Several international developments and ongoing initiatives• Better methods, databases, software• Lack of consensus• Increasing harmonisation needed in LCA practice
• LCA of bioenergy systems• Methodological choices in LCA determine results• Biomass/biofuels not necessarily better• Indirect effects important• All models are wrong, some are useful
• Non‐shifting of burdens
¨It is much more important to be able to survey the set of possible systems approximately than to examine the wrong system exactly. It is better to be approximately right than precisely wrong.”
Tribus and El‐Sayed (1982)
Thank you!