sustainability assessment of biofuels in a life cycle ......sustainability assessment of biofuels in...
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Sustainability Assessment of Biofuelsin a Life Cycle Perspective
Shabbir H GheewalaProfessor and Head
Life Cycle Sustainability Assessment LabThe Joint Graduate School of Energy and Environment
King Mongkut’s University of Technology Thonburi
ILCAN workshop on LCA research in Indonesia2-3 November 2016, Tangerang
What are biofuels?First Generation Biofuels
Biofuel Type Biomass Feedstock Production ProcessVegetable/PlantOil
Oil crops (e.g. rapeseed,sunflower, soybean, palm,jatropha, coconut, etc.) Algae
Cold pressing/ extraction
Biodiesel Cold pressing/ extraction &transesterification
Bioethanol sugarcane, cassava, sweetsorghum, sugar beet, grains
Hydrolysis and fermentation
Bio-ETBE Bioethanol Chemical synthesis
Advanced BiofuelsBiofuel Type Biomass Feedstock Production ProcessBiodiesel Vegetable oils and animal fat Hydtro-treatmentBioethanol Lignocellulosic material Advanced hydrolysis &
fermentationSyntheticbiofuels
Lignocellulosic material(BTL, FT Diesel, Bio-DME)
Gasification & synthesis
Bio-hydrogen Lignocellulosic material Gasification & synthesis or biol.
SUSTAINABILITY ISSUES FOR BIOFUELS
Possible benefits of biofuels
• Environmental– reduced greenhouse gas emissions
• Economic– utilization of local resources– reduced energy imports
• Social– rural development / stabilization of farmer
incomes
Shabbir H. Gheewala, JGSEE
Biomassharvesting
Biomass conversionto Biofuel
Distribution
CO2e
Why are biofuels considered green?
Solar Energy
Biofueluse
CO2eCO2e
CO2e
CO2e
Land use change
Biomassproduction
Shabbir H. Gheewala, JGSEE
Expanding system boundaries of biofuels
• only use phase – carbon neutral
• from the cultivation to end use – carbon benefits achievable
• expand the boundary further to include land use changeeffects – carbon benefits questionable– sugarcane cultivation on grassland – net benefits feasible
• ripple effects throughout the whole world– how does reduced soybean production in the US affect palm oil prices
(and probably impacts too) in Thailand?
– what if biofuel production results in displaced food production atanother location where forests are cleared?
– should these be part of the "environmental baggage" of the biofuel?
Shabbir H. Gheewala, JGSEE
Life cycle diagram of cassava ethanol production
Cassava farming
Molecular sievedehydration
Raw material prep.
Transport of freshcassava
Fertilizer, Agro-chemicals, Diesel
UASB treatment
Steam production
Electricity, Coal, Water
1000 L ethanol
Liquefaction
Fermentation
Distillation
Ponds
Chemicals, Yeast,Enzyme Biogas
Diesel Coal
Silalertruksa T, Gheewala, SH (2009), Energy 34(11): 1933–1946
Seed ,Fertilizer,
Herbicides,Diesel
Oil palmplantation
Palm oil milling
Kernel DecantercakeShell Fibre POME EFB
CPO(1,000 kg)
FFB(4,826 kg)
PKO & PKE
Sold asbiomass
fuel
Steam &Power
production
Openponds
Dumping Dumping
Fly ash
CH4
Anaerobicdigestion
Co-compostingwith POME
SCENARIOS
Fertilizer
Biogas
Diesel,Electricity
Diesel
Silalertruksa T, Gheewala SH (2012), Energy43(1): 306-314
Biofuels and food security
• Biofuels one of a number of factors driving up globalfood prices in recent times
• Higher food prices a threat to the poor net foodbuyers
• However, poor net food sellers can benefit from foodprice increases
• Shifting from food staples to biofuel feedstocks –reliance on such income increases vulnerability toexternal shocks
Shabbir H. Gheewala, JGSEE
Revisiting sustainability issues
• Greenhouse gas emission reductions– Conversion of forest land / high carbon stocks
– Indirect land use change
• Energy use– Life cycle energy use – net energy ratio
– Replacing one import with another?
• Competition with food– Competing land use / water use
– Effect on food prices
Shabbir H. Gheewala, JGSEE
SOME STUDIES FROM THAILAND
Comparisons of GHG emissions of biofuels in Thailand
g CO2-eq/MJ biofuels
Diesel = 85 g CO2eq/MJ
Gasoline = 90 g CO2eq/MJ
Biomass stock and Soilcarbon stock loss
IncreaseC-stock
Silalertruksa T, Gheewala SH (2012), Journal of Industrial Ecology 16(4): 541-551Silalertruksa T, Gheewala, SH (2011), Environmental Science and Technology 39: 834-843
LUC for palm biodiesel in ThailandLUC iLUC effects GHG emission factors for LUC
(MgCO2eq ha-1y-1)GHG from
palm biodiesel
Direct Indirect Total (gCO2eq MJ-1)
Rubber to Oilpalm
Grassland – Rubber -2.15 -1.59 - 3.74 (-5) - 14Forest – Rubber -2.15 11.09 8.94 75 - 95
Cassava to Oilpalm
Grassland – Cassava -2.68 2.35 - 0.33 16 - 36Forest – Cassava -2.68 15.03 12.35 96 – 116
Paddy to Oilpalm
No iLUC due tosurplus paddy -1.71 0 - 1.71 8 - 27
Set aside landto Oil palm No iLUC -1.52 0 -1.52 9 - 28
Forest to Oilpalm No iLUC 33.34 0 33.34 218 – 248
Silalertruksa T, Gheewala SH (2012), Journal of Industrial Ecology 16(4): 541-551
Prapaspongsa T, Gheewala SH (2016), Journal of Cleaner Production 134: 563-573
Potential GHG emissions per L ethanol in Thailand
kgCO2eq
Water deprivation from palm oilexpansion in Thailand
Water requirement for oil palmcultivation• crop water requirement (CWR)• ETc = Kc × ET0• Effective rainfall
Potential impact on water use• water stress index (WSI)
• Water deprivation
Water deprivation (m3H2Oeq unit-1) = Water deficit (m3 unit-1) × WSI
Pfister et al., 2009; Ridoutt B. and Pfister S., 2010; Gheewala et al. (2013)Allen, 1998; RID, 2011
Watersheds WSI
(3) Ping 0.023
(4) Wang 0.021
(5) Yom 0.044
(6) Nan 0.015
(7) Khong 0.014
(8) Chi 0.471
(9) Mun 0.927
(10) Chao Phraya 0.339
(11) Sakae Krang 0.031
(12) Pasak 0.050
(13) Thachin 0.287
(14) Mae Klong 0.018
(15) Petchaburi 0.022
(16) West Coast Gulf 0.158
(17) Prachin Buri 0.016
(18) Bang Pakong 0.026
(19) Thole Sap 0.019
(20) East-Coast Gulf 0.015
(21) Peninsula-East coast 0.067
(22) Tapi 0.060
(23) Thale sap Songkhla 0.014
(24) Pattani 0.025
(25) Peninsula-West coast 0.012Gheewala et al. (2014), Water 6(6): 1698-1718
Watersheds WSI
(1) Salawin 0.017
(2) Kok 0.018
Water deprivation of palm oil expansionin Thailand
• The suitable areas by the MOAC: threeregions falling under 13 watersheds
• Two boundaries: administrative andhydrological
• Excluding the potential to stress wateravailable at the watershed scale: Mun,Chao Phraya and West Coast Gulf.
• Scenario 1 assumes to takes place totallyin the East, Central, or South. The areadistribution in Scenario 2 is 79% in theSouth, 18% in the East and 3% in theCentral region.
Nilsalab et al. (2016), International Journal of Life Cycle Assesssment
Water deprivation of palm oil expansionin Thailand
• Central region potentially faces more water stress than cultivatingoil palm in other regions
• To cultivate oil palm in the South (Scenario 1) would berecommended in order to avoid the potential risk of water stress inthe Central region of (Scenario 2)
• The most advantageous option for Scenario 1 is in the East• The recommended watersheds:
– East: East Coast Gulf with 51%, Bang Pakong with 33%, Prachinburiwith 9%, and Thole Sap with 7%.
– South: Peninsular East Coast with 35%, Peninsular West Coast with33%, Tapi with 23%, Thale Sap Songkhla with 8%, and Pattani with 1%
• The recommended provinces: Nakhon Si Thammarat and Trat
Nilsalab et al. (2016), International Journal of Life Cycle Assesssment
Objective• Apply the WF and WSI approaches to help
policy makers to understand the impacts ofbioethanol production on water use and stress;
Scope of the assessment• 48 registered bioethanol plants located
nationwide are evaluated;
• Relevant to 26 provinces and 11 watersheds;
• Impact is evaluated by the characterizationfactor so called “water deprivation potential”
Water deprivation from feedstock expansion inThailand: Bioethanol
Gheewala et al. (2013), Bioresource Technology 150: 457–465
Share of irrigation waterrequirements for bioethanolproduction in 2021 classified bywatersheds
Share of water deprivationpotentials from bioethanolproduction in 2021 classifiedby watersheds
Implications of the bioethanol policy mandate onwater use and stress
Gheewala et al. (2013), Bioresource Technology 150: 457–465
Recommendations to enhance water efficiencyof bioethanol production in Thailand• Crop evapotranspiration (ET) reduction
– Yield improvement (High yield varieties development, good agriculturalpractices in farming)
• Promotion of sugarcane ethanol (as nowadays there is onlyone ethanol plant using sugarcane juice in operation)
• Enhancing water use efficiency in feedstock processing andethanol conversion (water reuse and recycling program)– New technologies development such as dry cleaning of sugar cane to
eliminate sugarcane washing, treatment of vinasse by biodigestiontechnique to reduce the organic load and recirculating into the process(Macedo, 2005; Macedo et al., 2008)
• Promotion of bioethanol feedstock cultivation in the lowwater stress areas
Gheewala et al. (2013), Bioresource Technology 150: 457–465
Farmer Sugar Factory
Sugar
Molasses
Fertilizer Plant
BagasseElectricity
Waste Water
Ethanol
Ethanol Plant
Power Plant
Fertilizer
Filter Cake;Cane dirties
Steam
Cane trashpotentially forpower generation
Biorefinery complex
Net feedstock balances (after accounting forthe projected bio-ethanol demand)
Net balance (M.tonfeedstocks/year) 2008 2009 2010 2011 2016 2022
Scenario 1: Lowyields improvement
Molasses 0.13 0.54 0.65 0.62 0.23 (0.17)Cassava 3.50 0.54 (2.11) (3.61) (13.00) (20.95)Sugarcane 4.33 8.26 8.49 7.03 6.24
Scenario 2:Moderate yieldsimprovement
Molasses 0.13 0.81 1.13 1.31 0.81 (0.08)Cassava 3.50 1.23 0.64 1.19 (6.95) (20.63)Sugarcane 10.24 18.75 23.55 19.60 8.23
Scenario 3: Highyields improvement
Molasses 0.13 0.81 1.13 1.31 1.42 1.44Cassava 3.50 1.23 0.64 1.19 (0.23) (0.48)Sugarcane 10.24 18.75 23.55 32.79 41.18
Silalertruksa T, Gheewala SH (2010), Energy Policy 38(11): 7476-7486
Scenario 1: Crop yields are projected to grow as usual as if there is no policy on biofuels developmentScenario 2: Crop yields are anticipated to be improved as per the government’s short-term policy targets inThailand’s 15 years renewable development planScenario 3: Crop yields are projected to increase to reach the genetic potential of the cassava andsugarcane varieties
Numbers in parentheses indicate shortfall
Net feedstock balances (after accounting forfood and stocks)
Net balance (M.tonfeedstocks/year) 2008 2009 2010 2011 2016 2022
Feedstock supply potentialsPlanted area (M.hectare) 0.58 0.67 0.75 0.83 0.91 0.91Harvested area (M.hectare) 0.46 0.51 0.55 0.59 0.91 0.91Yield (ton/hectare) 20.2 18.6 19.7 20.8 21.9 21.9FFB production (M.ton FFB) 9.27 9.57 10.78 12.20 19.95 19.95CPO production (M.ton CPO) 1.68 1.74 1.96 2.22 3.63 3.63Feedstock requirements for biodieselBiodiesel production targets (ML/d) 1.23 1.56 2.28 3.00 3.64 4.50CPO required (M.ton/year) 0.42 0.54 0.78 1.03 1.25 1.54FFB required (M.ton FFB/year) 2.32 2.94 4.30 5.66 6.87 8.49Net feedstock balancesNet CPO balance (M.ton CPO) 0.15 0.09 0.03 (0.01) 0.88 0.07
Silalertruksa T, Gheewala SH (2012), Journal of Industrial Ecology 16(4): 541-551
Commodity Price Rise Caused by Biofuel in Thailand
Kochaphum C, Gheewala, SH, Vinitnantharat (2012), SEE 2011, Bangkok, Thailand
lnPBPO = 1.925 + 0.414 lnPCPO + 0.118 lnPCO + 0.019 lnDB100en
Employed persons (person-years) of biofuelsproduction in Thailand
Silalertruksa T, Gheewala SH, Fritsche U, Hunecke (2012), Biomass and Bioenergy 46: 409-418
Enhancing sustainability benefits of biofuels
• Investment in increasing agricultural productivity andprocess innovation
• Efficient utilization of byproducts
• Prioritizing biofuel feedstocks from land not incompetition with other uses
• Establishing a proper support policy framework
Shabbir H. Gheewala, JGSEE
Next LCA Agrifood Asia Workshop: 10-12 Oct 2017 in Kuala Lumpur, MY
