Footprinting farms: a comparison of three GHG calculators

Figures & data

Table 1. Overview of the three GHG calculator tools for comparison.

	GHG calculator tool
	CFT	Bonsucro calculator	Palm GHG
Developer(s)	University of Aberdeen, Unilever and SFL	Dr P. Rein, University of Louisiana in collaboration with Bonsucro	RSPO GHG ERWG (Emission Reduction Working Group)
Accessibility	Open access – available online for download	Access through Bonsucro membership and Bonsucro training	Open access – available online for download
Format and version	Excel spreadsheet. Version 2.0 (September 2012) (online version under development)	Excel spreadsheet. Version 1.0 (August 2012)	Excel spreadsheet. Beta version 1a (December 2012)
Applicability	Multi-crop; globally relevant	Sugarcane, sugar, ethanol from sugarcane; sugarcane growing regions globally	Crude palm oil (CPO), palm kernel oil (PKO), palm kernel expeller (PKE); palm oil growing regions globally
Aim of tool	Provide decision-support to farmers to enable management practice changes to promote GHG mitigation	Evaluate conformity against the maximum level of emissions set in the Bonsucro Production Standard for sugarcane, sugar and sugar-based ethanol production and identify options for improvement	Enable palm oil producers to estimate the net GHG emissions of palm oil products throughout the production chain to identify options for improvement and to report on changes in GHG emissions
Units of measurement	Whole farm	Farm and mill (t CO2 e/t produced sugar) or (g CO2e/MJ biofuel)	Farm (estates, smallholdings and mill and kernel crushing plants. Reporting units:
	Per unit production (kg CO2e/tonne crop) or per land area (kg CO2e/ha)	Per unit agricultural production (kg CO2e/t sugarcane)	(t CO2e/ha)
			(t CO2e/t FFB)
			(t CO2e/t CPO)
			(t CO2e/t palm kernel (PK))
Allocation method(s) employed	Economic allocation of co-products, details specified by tool user	Economic allocation of sugar and molasses	Mass allocation of net emissions between CPO and PK and subsequently between PKO and PKE
		Physical allocation based on energy content between sugar and ethanol
Current usage	Several examples of use within supply chain companies and other wider initiatives to engage with and collect data from farms	Mill certification under Bonsucro system	RSPO led pilot assessments with mills and growers (Bessou et al., 2014). Recent (2013) incorporation into the RSPO principles and criteria for the production of sustainable palm oil
Ref. (website/publication/user-guide)	Download from: www.coolfarmtool.org	No resources currently publicly available for the calculator. Other resources related to Bonsucro production standard (http://bonsucro.com/site/production-standard/)	Download from: http://www.rspo.org/en/rspo_palmghg_calculator
	Publication: Hillier et al. (2011)		Guidance report: http://www.rspo.org/file/PalmGHG%20Beta%20version%201.pdf (Chase et al., 2012)

Figure 1. Schematics of the GHG emission sources included and excluded from this study assessment for (a) sugarcane, and for (b) palm oil systems.

Table 2. Emission sources considered by the three GHG calculators within the agricultural boundary.^a

GHG emission source^a,^b	Tool
	CFT	Bonsucro	PalmGHG
Fertilizer production (CO2)	Y	Y	Y
Transport of fertilizers to farm (CO2)	Y	Y	Y
(Direct fertilizer emissions) soil N2O emissions from fertilizer application	Y	Y	Y
Indirect N2O from soils from fertilizer application	Y	Y	Y
Pesticide production (includes herbicides, fungicides, insecticides, etc.)	Y	Y	N
Infrastructure (CO2)	N	N	N
Fossil fuel (CO2)	Y	Y	Y
Electricity (CO2)	Y	Y	N (considered in the mill phase only)
Renewable energy generation	Y	N	Y
Crop/mill residues (N2O)	Y	Y	Y
Enteric CH4	Y	NR	NR
Manure CH4	Y	NR	NR
Biomass burning	Y	Y	N
Change in soil C stock from direct LUC	Y	Y	Y (C- and N-related emissions due to peat oxidation; not included for mineral soils)
Change in biomass C stock from direct LUC (sequestration in above and below ground biomass)	Y	Y	Y
Indirect LUC	N	N	N
Peat soils (N2O, CO2)	N	N	Y
Rice (CH4)	Y	NR	NR
Soil C changes due to management changes (tillage, composts, etc.)	Y	N	N
Transport of workers/materials on farm	Y	N	Y (included in total fuel use)
Co-product emissions^c	Y (user-specified co-products)	Y (ethanol, molasses, and sugar)	Y (CPO, PK, and PKO)
Allocation options	None specified as default, user-defined allocation. (economic allocation can be used for co-products)	GHG emissions allocated to sugar and ethanol on an energy basis (57% to sugar, 43% to ethanol) (physical allocation)	Mass (allocation between CPO and PK and between PKO and PKE); system expansion for energy co-products (surplus electricity; PK Shells sold to industrial furnaces)
		Energy inputs allocated to molasses by economic allocation
GHGs considered	CO2, N2O, and CH4	CO2, N2O, and CH4	CO2, N2O, and CH4

^aY, Yes it is included; N, No it is not included; NR, it is not relevant to the crop-specific system and is therefore not included.

^bOther emission sources from processing may be included in the calculator but are not demonstrated in the scope of this assessment.

^cCo-products within and outside of the agricultural boundary, that is, those resulting from the milling of the raw agricultural material, are also indicated here.

Table 3. GHG driver 1: agricultural inputs.

	CFT	Bonsucro	PalmGHG
General approach	CFT combines several empirical models for GHG emissions from agricultural inputs including a fertilizer model based on over 800 data sets (Bouwman et al., 2002), with IPCC tier 1 inventory methods and EFs	The calculation approach is similar to and adapted from the EBAMM model (Farrell et al., 2006), which itself is similar to the GREET model (Wang et al., 2008), modified for sugarcane. The calculator uses IPCC EFs	PalmGHG is based on an earlier model, GWAPP developed by Chase and Henson (2010). It is based on a life-cycle approach specific to global warming impacts. The tool uses both literature data sources and IPCC EFs, combined with oil palm growth models to simulate C sequestration by the crop
Fertilizer production (kg CO2e/kg)	Fertilizer production emissions are specified for a range of fertilizer types (35 fertilizers modelled). Four options are specified for fertilizer production technology used: current tech, new tech, old tech, and older tech Key fertilizers modelled: (kg CO2e/kg)Limestone: 0.006Ammonium nitrate (35% N): 3.042Muriate of potash (MOP) (60% K2O): 0.265Urea (46.4% N) – 2.551Ref(s): Ecoinvent (2002, 2007) and Kongshaug (1998)	Production of N fertilizer is specified, and production and transportation of limeKey fertilizers modelled: (kg CO2e/kg)N fertilizer production: 3.99P fertilizer production: 0.714K fertilizer production: 1.61Lime production and transportation: 0.065Ref(s): Bonsucro production standard appendix 3 (Bonsucro, 2011) and in (Macedo et al., 2008; IPCC, 2006a)	Fertilizer production emissions are specified for nine synthetic fertilizersKey fertilizers modelled: (kg CO2e/kg)Ammonium nitrate (34% N) – 2.380Muriate of potash (MOP) (60% K2O) – 0.2Urea (46% N) – 1.34Ref(s): Jenssen and Kongshaug (2003) and Ecoinvent (2010)
Fertilizer application, direct and indirect N2O emissions	Multivariate empirical model of Bouwman et al. (2002) is used to calculate nitrous oxide (N2O) and nitric oxide (NO) emissions associated with fertilizer application. Emissions from fertilizer application differ for different types of fertilizers applied. Option for user to define own fertilizer blend using a base fertilizerRef(s): Bouwman et al. (2002) and FAO/IFA (2001) (for ammonia)	Fertilizer application emissions differentiated between N, P, K2O and lime with specified EFs for per kg N applied: 6.2 kg CO2e/kg N	Direct and indirect fertilizer-induced emissions are calculated according to IPCC tier 1 and are differentiated between nine widely used synthetic fertilizers in palm oil cultivation. Additional fertilizers can be included if the user requiresRef(s): IPCC (2006a), Jenssen and Kongshaug (2003), Ecoinvent (2010), and Chase and Henson (2010)
		Lime: 0.44 kg CO2e/kg lime (assumes all C in lime becomes CO2)Ref.: IPCC (2007)
Crop residues and organic inputs	Able to model:	Models:	Models:
	Compost – as zero emissions or aerated or non-fully aerated productionSlurry – from livestock typesStrawResidue N content dependent on crop type under assessmentSugarcane (Millet): 0%Palm oil (tree crop): 0.0123%Various residue treatment options modelledRef(s): IPCC (2006a) and Smith et al. (1997)	Cane residue left in field post burning: N content 0.5%Filter cake: N content 12.5%Vinasse: may be applied as a fertilizerAssumed 1.225% of N in the residue is converted to N in N2ORef.: Macedo et al. (2008)	EFB – 0.22 t/t FFB, N content 0.32%*POME – 0.5 t/t FFB, N content 0.045%**N contents and production rates can be modified by the userRef(s): Yacob et al. (2005) and Singh (1995)
N runoff, leaching rate	30% for moist soils, none for dry	Not specified	30%
	Ref.: IPCC (2006a)		Ref.: IPCC (2006a)
Pesticides	Average emissions factor for all pesticides (based on production emissions)are included per application dose: 20.5 kg CO2e	Insecticide EF: 29.09 kg CO2e/kg Herbicide EF: 25.05 kg CO2e/kgRef.: Macedo et al. (2008)	Not included
	Ref(s): average generated from: Audsley (1997) and Green (1987)
Management inputs	IPCC tier 1 method is used to estimate soil C stock changes and the changes due to management practices are defined by Ogle et al. (2005). They are modelled on an annualized basis and are dependent on several farm characteristics including climate	Not included	Not included
GWP values	N2O: 296	N2O: 298	N2O: 298
	CH4: 25	CH4: 25	CH4: 22.25 (bio-methane, for example, from POME)
	Ref(s): IPCC (2001), IPCC AR4 (2007) and Smith et al. (2007)	Ref(s): IPCC AR4 (2007) and BSI (2008)	Ref(s): IPCC AR4 (2007), Chase and Henson (2010) and Muñoz, Rigarlsford, Canals, and King (2012)

Note: EBAMM, Energy and Resources Group (ERG) Biofuel Analysis Meta-Model.

Table 4. GHG driver 2: Energy.

	CFT	Bonsucro	PalmGHG
General approach and activity data required	Reported on a total annual consumption basis per fuel type used with the option to specify several fuel types. Alternatively/in addition, emissions arising per machine operation for various practices can be calculated based on number of operations, fuel used and other farm characteristics stated	Total annual fuel use per fuel type across all agricultural activities is reported. Electricity used in irrigation is reported separately	Recorded as total fuel consumption (of diesel and petrol) in one year of plantation lifetime. It includes emissions due to field operations that arise from fossil fuel consumed by machinery for transportation and other field operations
Fuel EFs
Gasoline/petrol (kg CO2e/L of fuel)	2.32	2.81	3.12 (Assumed as diesel)
	Ref.: GHG Protocol (2003)	Ref(s): Farrell et al. (2006), Shapouri, Duffield, McAloon, and Wang (2004), Graboski (2002) and Macedo et al. (2008)	Ref.: JRC, EUCAR, and CONCAWE (2011)
Diesel (kg CO2e/L of fuel)	2.68	3.46	3.12
	Ref.: GHG Protocol (2003)	Ref(s): Farrell et al. (2006), Shapouri et al. (2004), Graboski (2002) and Macedo et al. (2008)	Ref.: JRC et al. (2011)
Fuel oil (kg CO2e/MJ)	0.0784 kg CO2e/MJ	0.096 kg CO2e/MJ	Not included
	Ref.: GHG Protocol (2003)	Ref.: Farrell et al. (2006) (EBAMM)
Natural gas (kg CO2e/MJ)	0.0628 kg CO2e/MJ	0.066 kg CO2e/MJ	Not included
	Ref.: GHG Protocol (2003)	Ref.: Farrell et al. (2006) (EBAMM)
Coal (kg CO2e/MJ)	0.0927 kg CO2e/MJ	0.107 kg CO2e/MJ	Not included
	Ref.: GHG Protocol (2003)	Ref.: Farrell et al. (2006) (EBAMM)
Electricity (kg CO2e/MJ)	Country-specific values for kg CO2e/MJ grid electricity are included in the tool	Country-specific values for kg CO2e/MJ grid electricity should be specified. Values stated in Bonsucro production standard	Not included in the agricultural phase
	Value for Brazil: 0.02	Value for Brazil: 0.02
	value for Indonesia: 0.21	Value for Indonesia: 0.22
	Ref.: IEA (2009 figures)	Ref.: RFA (2008)
Renewable electricity sources (kg CO2e/MJ)	Option to include emissions generated from the use of renewable electricity sources:	Not included	Not included
	Hydro: 0.0017
	Wind: 0.033
	Photo-voltaic: 0.01972
	Ref.: Ecoinvent (2007)
Specific machine operation energy consumption	Simplified model for fuel use as a function of machinery operations for basic farm management practices (tilling, harvesting, etc.). for differing soil types and yields	Electricity used in irrigation (including vinasse distribution) is modelled separately using the same EF for electricity	No specific machine operations included
	Ref.: ASABE (2006a, 2006b)	No other specific machine operations included
Energy used in transportation of inputs to farm	Calculated based on quantity transported, distance travelled and mode of transport and vehicle/vessel type. Option for weight of vehicle to be included also	Transport emissions calculated as 0.05 kg CO2e/kg input material transportedRef.: Wang et al. (2008)	Transport of fertilizers from production sites to field are included based on shipping and motor vehicle emissions0.31 kgCO2e/km.t (assumes 2l diesel/km at 20t per trip)Ref.: www.searates.com; Chase and Henson (2010)

Table 5. GHG driver 3: LU and LUC.

	CFT	Bonsucro	PalmGHG
General approach	User specifies broad category of LUC that has occurred, with more specificity if forest land; how long ago the change occurred and the percentage of the total land area converted. If converted from forest the user can state the age of the forest when felled	Emissions from any land use change are calculated outside of the tool using values given in: http://shop.bsigroup.com/upload/Shop/Download/PAS/PAS2050.pdf	Emissions from land clearing by burning are calculated based on user-specified percentage of crop burnt
			Emissions are calculated for land clearing each year and averaged over the full crop cycle. ‘Own crops’ and ‘out-growers’ can be modelled separately, as can emissions arising from mineral soils and peat soils. The user is required to specify how much land area was changed from different previous land use types at planting and the amount of C lost is then amortized over the expected crop cycle
Previous land use types included:	Forest land (several types)	Forest land	On mineral soils:
	Tropical forest	Grassland	Primary forest
	Tropical moist deciduous forest	Crop land	Logged forest
	Tropical dry forest		Coconut
	Tropical shrubland		Rubber
	Tropical mountain system		Cocoa under shade
	Sub-tropical humid forest		Oil palm
	Sub-tropical dry forest		Secondary re-growth
	Sub-tropical steppe		Shrubland
	Sub-tropical mountain system		Food crops
	Temperate oceanic forest		Grassland
	Temperate continental forest
	Temperate mountain system		On peat soils:
	Boreal coniferous forest		Logged forest
	Boreal tundra forest		Food crops
	Boreal mountain system		Secondary re-growth
	Grassland		Oil palm
	Arable
Land use carbon stocks	PAS 2050 default values used	PAS 2050 default values used	Defined in Agus et al. (2012)
Peat soil emissions	Not included specifically (soil characteristics can be modified to be more representative of peat soil)	Not included	Emissions from oxidation of organic carbon and associated N2O emissions from peat cultivation based on water table depth and management
			Calculation: 0.91 (t CO2e/ha/yr) × cm drainage depth
			Ref.: Hooijer et al. (2010)
Burning/combustion (pre- or post-crop harvesting)	Not included specifically (however can be modelled through specifying burning as the treatment of crop residue)	Emissions from cane burning are based on IPCC EFs for burning biomass (0.07 kg N2O/t dry matter and 2.7 kg CH4/t dry matter)	Not included
		Ref.: IPCC (2006a)
C stock changes related to management practices (e.g. tillage, composting, planting preparation etc.)	IPCC tier 1 method employed for estimating soil C stock changes. Changes determined by Ogle et al. (2005) for a period of 20 years.	Not included. (changes in C content of soils other than those from direct land use change are excluded)	Not included
LULUC-induced soil C stocks	Defined by Ogle et al. (2005)	Not included	Not included (for mineral soils)
Amortization	20 years	Not included within the tool	Default is 25 years (but can be modified by user)
	Ref(s): IPCC (2006a) and BSI (2011)		Ref(s): Chase and Henson (2010)
Crop sequestration in assessment crop	Not included (unless modelled specifically under crop sequestration tab)	Not included (biogenic sources of carbon are excluded except those resulting from direct LUC)	Direct measurements preferable otherwise modelled data are used based on Southeast Asian conditions to produce annual values for standing biomass (above and below-ground), ground cover, frond piles and other plantation litter
Carbon content of biomass	50%	Not included	45 or 46%
			Ref.: Chase et al. (2012)
Sensitivities	Unable to model different land use change scenarios in the same spreadsheet	NA	Differences in crop ages throughout the plantation are captured
Underlying models incorporated	Several data sets and allometric growth models from IPCC (2006a) to model carbon storage in tree crop systems	Not included	OPRODSIM and OPCABSIM (vigorous growth for own crops and average growth for out-growers
			Ref(s): Henson (2005, 2009)

Table 6. Input data for sugarcane assessment (base case).

Information category	Input	Data entry/quantity	Units	Source/reference	Tool(s) using the data
General information	Crop type	Millet		Closest representation to sugarcane as an option in the CFT	CFT
	Yield	1,700,372	Ha	Specified by N. Viart (personal communication, November 10, 2012)	Both
	Production area	27,231	Tonnes		Both
	Climate	Tropical: annual average temperature: 18	°C		CFT
Soil properties	Soil type	Medium			CFT
	SOM content	1.72 < SOM≤5.16			CFT
	Soil moisture	Dry			CFT
	Soil drainage	Good			CFT
	Soil pH	≤5.5	pH		CFT
Fertilizers applied	Nitrogen (N) [as urea in CFT]	65.7	kg/ha		Both
	Phosphorus (P) [as triple super phosphate in CFT]	39.5	kg/ha		Both
	Potassium (K) [as potassium sulphate in CFT]	65.9	kg/ha		Both
	Lime [as limestone in CFT]	236.7	kg/ha		Both
Fertilizer related information	Fertilizer application method	Incorporate			CFT
	Emissions inhibitors in fertilizers	None			CFT
	Fertilizer production technology	Current technology			CFT
Organic inputs	Filter cake [as zero compost emissions in CFT]	3400	kg/ha		Both
Pesticide application	Herbicide	3.96	kg/ha		Bonsucro
	Insecticide	0.71	kg/ha		Bonsucro
	Number of applications	4	Applicat-ions/yr	Specified by N. Viart (personal communication, September 12, 2013)	CFT
Transport of inputs	Quantity transported	11,104	tonnes	Authors’ assumptions
	Mode of transport/distance transported	Heavy goods vehicle/200	Vehicle type/km
Energy use	Gasoline	100	l/ha	Authors’ assumptions	Both
	Diesel	7,212,659 (264.87 litres per ha)	Litres per year	Specified by N. Viart (personal communication, November 10, 2012)	Both
	Natural gas	50	kWh/ha	Authors’ assumptions	Both
	Electricity	90	kWh/ha	Authors’ assumptions	Both
Crop residue	EM quantity	3126	Kg/ha	Specified by N. Viart (personal communication, November 10, 2012)	Both
	Treatment	Left on field; incorporated or mulch			CFT
Land clearing	Sugarcane burnt	48.05	% of crop		Bonsucro
		30	t cane/ha		Both
Land use change Scenarios modelled	Forest to arable cropland	100% land conversion	%	Authors’ assumptions for comparison purposes only	Both
	Forest to perennial cropland				Bonsucro
	Forest to grassland				CFT

Table 7. Input data for palm oil assessment (base case).

Information category	Input	Data entry/quantity	Units	Source/reference	Tool(s) used in
General information	Crop type	Tree crop		Closest representation to oil palm as an option in the CFT	CFT
	Yield	195,333	Tonnes	Specified by M. Chin (personal communication, June 8, 2012)	Both
	Production area	6822	ha		Both
	Climate	Tropical: annual average of 18	˚C		CFT
Mineral soil properties	Soil type	Fine			CFT
		Mineral soil			PalmGHG
	SOM content	1.72 < SOM ≤5.16	%		CFT
	Soil moisture	Moist			CFT
	Soil drainage	Good			CFT
	Soil pH	≤ 5.5	pH		CFT
Peat soil properties	Soil type	Fine soil			CFT
		Peat soil			PalmGHG
	SOM content	10.32 < SOM	%		CFT
	Soil moisture	Moist			CFT
	Soil drainage	Poor			CFT
	Soil pH	≤5.5	pH		CFT
	Water table	Actively managed	Y/N	(defaults: not actively managed = 80; actively managed = 60) RSPO PLWG (2012)	PalmGHG
		Depth of water table	Cm
Fertilizers applied	Ammonium nitrate	80	kg/ha	Specified by M. Chin (personal communication, June 8, 2012)	Both
	Urea	20	kg/ha		Both
	Kierserite	70	kg/ha		Both
	Murate of Potash	200	kg/ha		Both
	Triple super phosphate	70	kg/ha		Both
	Ammonium sulphate	80	kg/ha		Both
Organic inputs	FFB	0.22	t/t FFB		Both
	POME	0.5	t/t FFB		Both
Pesticide application	Number of applications	3	Applications per year	I. Henson, personal communication (May 2013)	CFT
Transport of inputs	Quantity transported	3525	tonnes	Authors’ assumptions	Both
	Mode of transport/distance transported	Road, light goods vehicle/50	Vehicle type/km
	Mode of transport/distance transported	Ship/4000	Vehicle type/km
Energy use	Diesel	388,333	Litres per year	Specified by M. Chin (personal communication, June 8, 2012)	Both
		56.924	Litres per ha
Crop residue	Frond piles and plantation litter (residue)	8.54	t biomass/ha	I. Henson, personal communication (May 2013)	CFT
Land use change Scenarios modelled	Forest to plantation	100% land conversion	%	Authors’ assumptions for comparison purposes only	PalmGHG
	Forest to arable cropland				CFT
	Forest to grassland				CFT

Table 8. Issues faced and assumptions made during the GHG assessments with the calculators.

GHG source (crop system)	Issue	Tool	Assumption and justification
Land clearing (sugarcane)	No specific data input option for land clearing by combustion	CFT	Modelled under residue management functionality, ‘burned’. Residue quantity equated to the amount of dry matter burnt per hectare
Pesticides (sugarcane)	Quantity of different pesticide types present for Bonsucro. Unknown number of applications per year for CFT data entry	CFT	Assumed four applications including one application pre-planting (N. Viart, personal communication, September 12, 2013)
Residual EM (sugarcane)	Quantity of EM is calculated within Bonsucro but unavailable for CFT. A calculation was performed external to the tools:	CFT	Estimated 3125.75 kg/ha residue left in field/incorporated or used as mulch
	= 3126 kg/ha
Transport of fertilizers (sugarcane)	Information on; distance of fertilizer production to farm; mode and type of vehicle; and if (for road) it returned empty or not, unavailable	CFT	Assumptions made were^a:
			Distance: 200 kmMode: roadVehicle: heavy goods vehicleReturn: returning empty
Fertilizer production technology (sugarcane; palm oil)	Unknown state of technology	CFT	Assumed current technology (default option in CFT)
Amortization of carbon stock biomass loss (sugarcane; palm oil)	GHG emissions for biomass loss are accounted for in the year they are lost and not amortized (this is based on IPCC accounting for national inventories	CFT	A 20-year amortization period was applied to the biomass loss GHG emissions for sugarcane and 20- and 25-year amortisation periods were used for palm oil data
EFB and POME (palm Oil)	No equal or closely equivalent fertilizers included in the CFT	CFT	Modelled under zero emissions compost (1% N) and cattle slurry (0.26% N) as the closest fertilizers with a low N content to reflect that of EFB and POME
Farm situation (palm oil)	Modelling different farm properties	PalmGHG	Assumed to be own crop only (no out-growers modelled), mineral soils only (no peat modelled)
Three-year rolling average (palm oil)	PalmGHG requires three years of data input and uses the average value to calculate the GHG footprint	PalmGHG	The same data set was entered for each of the three years to ‘force’ the tool to use the one-year data value as the average

^aAuthors' assumptions.

Figure 2. GHG emission hotspot results for sugarcane production generated by Bonsucro and the CFT (kg CO₂e/ha).

Figure 3. (a) GHG emissions from urea (N) fertilizer application in Bonsucro and various soil property scenarios in the CFT (S1–S4) and (b) fertilizer-induced GHG emissions for Bonsucro when using different fertilizer application methods in the CFT.

Table 9. GHG emission outputs and EFs for various fuel types included in Bonsucro and the cool farm tool.

Energy type and Input	Factor	GHG calculator		Percentage difference (%)
	Output	Bonsucro	CFT
Diesel (7,212,659 litres per year)^a	EF (kg CO2e/MJ)	3.46	2.68	25.4
	GHG output (kg CO2e/ha)	916	709.9	25.4
Gasoline (100 litres/ha)^b	EF (kg CO2e/l fuel)	2.81	2.32	19.1
	GHG output (kg CO2e/ha)	281.16	232	19.2
Electricity (90 kWh/ha)^c	EF (kg CO2e/MJ)	0.022	0.018	21.3
	GHG output (kg CO2e/ha)	7.13	5.75	21.3
Natural Gas (50 kWh/ha)^b	EF (kg CO2e/MJ)	0.0662	0.0628	5.2
	GHG output (kg CO2e/ha)	10.64	11.3	6
	Energy demand factor	1.12	N/A	N/A

^aBase case data set (from Table 2).

^bAuthors’ assumed quantity.

^cRein (2010).

Figure 4. GHG emissions from various land use change (LUC) scenarios for sugarcane modelled in Bonsucro and the cool farm tool.

Table 10. GHG emissions for LUC from forest to arable given different soil properties in the cool farm tool.

Tool scenario	LUC type specified	Soil property amendment (from base case, Table 2)	GHG output (kg CO2e/ha)
Bonsucro 1	Forest to arable	–	37,000
CFT 7	Tropical rainforest to arable	Soil type: fine	37,803
CFT 8	Tropical rainforest to arable	Soil type: coarse	43,472
CFT 9	Tropical rainforest to arable	Lower SOM: ≤1.72	39,892
CFT 10	Tropical rainforest to arable	Higher pH: >8.5	37,746

Figure 5. GHG emission outputs for palm oil generated by PalmGHG and the CFT across different GHG hotspots (kg CO₂e/ha).

Figure 6. GHG emission outputs for fertilizer production for a palm oil production system generated by PalmGHG and the CFT based on different data sets within the tools.

Figure 7. (a) GHG outputs for LUC scenarios for palm oil as modelled in PalmGHG and the CFT (kg CO₂e/ha) and (b) GHG outputs for LUC scenarios for palm oil on peat soils as modelled in PalmGHG and the CFT (kg CO₂e/ha).

Bessou, C., Chase, L. D. C., Henson, I. E., Abdul-Manan, A. F. N., Milà i Canals, L., Agus, F., … Chin, M. (2014). Pilot application of PalmGHG, the RSPO greenhouse gas calculator for oil palm products. Journal of Cleaner Production, 73, 136–145. doi:10.1016/j.jclepro.2013.12.008

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