7  Travel emission factors

This section provides detail on how to calculate emissions associated with business travel and staff commuting.

Business travel emissions result from travel associated with (and generally paid for by) the entity. We provide factors for private and rental vehicles, taxis, public transport, air travel, helicopters and accommodation. Business travel emissions are indirect (Scope 3/Category 6: Business travel) if the entity does not directly own or control the vehicles used for travel. If the entity owns or has an operating lease for the vehicle(s) these emissions are direct (Scope 1/Category 1: Purchased goods and services GHG Protocol) and should be accounted for in transport fuels (see Section 3.3).

Staff commuting emissions result from employees travelling between their homes and their worksites. Emissions from staff commuting may arise from the use of private and rental vehicles, taxis, public transport, and air travel. Other emissions associated with working from home can be accounted for in indirect business-related emission factors (see Section 6).

Staff commuting emissions are indirect (Scope 3/Category 7: Employee commuting Section 6.2.3).

7.1 Overview of emission factor changes from 2025 to 2026

Table 7.1: Summary of changes to travel emission factors
Section Total EFs EFs added EFs removed EFs changed Explanation for change
Accommodation 64 14 2 48 Cornell HSBI 2025 refresh changes hotel-stay factors and adds/removes country or scope rows.
Domestic Air Travel 8 0 0 8 Emission factors for medium/large aircraft 2024 are directly from AirNZ, and small-aircraft to reflect changes in updated fuel changes from MBIE.
Helicopter 5 0 0 5 Robinson R44/R22 fuel-consumption-rate correction is the main direct helicopter change; MBIE fuel changes also apply.
Individual Aircraft 18 0 0 18 MBIE fuel-property inputs changed and the aircraft calculation now uses the current fuel source path.
International Air Travel 16 0 0 16 DESNZ 2025 international air factors changed, including RF and non-RF values.
Light Passenger Vehicle 187 0 0 187 Changes are due to updated upstream fuel and electricity-related factors, plus corrected vehicle fleet year grouping.
Public Transport Passenger Travel 9 0 0 9 Auckland Transport FY2024/25 service data changed. Review bus, rail and ferry data, hydrogen service handling, ferry accounting and rail T&D treatment.
Public Transport Vehicle 9 0 0 9 Changes are due to updated purchased energy, transmission and distribution loss, and fuel factors, plus a corrected vehicle consumption calculation.
Taxi Travel 6 0 0 6 Changes are due to updated light passenger vehicle, fuel, and electricity-related factors.

For detailed information on the emission factor changes, download the Emission factor changes CSV file from Appendix G.

7.2 Passenger vehicles

This section covers emissions from private vehicles for which mileage is claimed, rental vehicles and taxi travel.

Travel, including rental vehicles, staff mileage and taxi travel are indirect (Scope 3) emissions. This is a change in guidance, to align better with leading practice. As with direct (Scope 1) emissions from transport fuels, the most accurate way to calculate emissions is based on fuel consumption data. Fuel-use data are preferable because factors such as individual vehicle fuel efficiency and driving efficiency mean that kilometre-based estimates of emissions are less accurate. However, this information may not be easily available.

The 2024 fleet statistics (Table 7.3, Table 7.4, Table 7.5 and Table 7.6) were taken from the Te Manatū Waka Ministry of Transport Vehicle Fleet Emissions Model. This provides energy (fuel and electricity) use per km travelled by vehicle.

Fuel-use based emission factors are provided in Section 3.3.

If the only information known is kilometres travelled, use the emission factors in this section. Factors such as individual vehicle fuel efficiency and driving efficiency mean that kilometre based estimates of carbon dioxide equivalent emissions are less accurate than calculating emissions based on fuel-use data.

If the vehicle size and engine type are known, use the factors in Table 7.3, Table 7.4, Table 7.5 and Table 7.6. The following Table 7.7 lists default private car emission factors and Table 7.8 lists the default rental car emission factors based on distance travelled. Table 7.9 lists emission factors for taxi travel based on dollars spent and kilometres travelled.

Table 7.2 details engine sizes and typical corresponding vehicles.

Table 7.2: Vehicle engine sizes and common car types
Engine size Vehicle size Example vehicles Comparative electric vehicles
<1350 cc Very small Fiat 500 Peugeot iOn
1350-<1600 cc Small Suzuki Swift Renault Zoe
1600-<2000 cc Medium Toyota Corolla Nissan Leaf
2000-<3000 cc Large Toyota RAV4 Hyundai Ioniq
>3000 cc Very large Ford Ranger Nissan e-NV200
Table 7.3: 2010 and earlier vehicle fleet emission factors per km travelled
Emissions Source Unit kg CO₂–e/unit CO₂/unit (kg CO₂–e) CH₄/unit (kg CO₂–e) N₂O/unit (kg CO₂–e)
Pre 2010 Fleet
Motorcycle: <60cc, petrol km 0.0655098 0.0627487 0.000838125 0.00192297
Motorcycle: ≥ 60cc, petrol km 0.13102 0.125497 0.00167625 0.00384594
Diesel vehicle: <1350 cc km 0.210175 0.206924 0.000310651 0.00294009
Diesel vehicle: 1350 – <1600 cc km 0.202254 0.199126 0.000298944 0.00282929
Diesel vehicle: 1600 – <2000 cc km 0.214366 0.21105 0.000316846 0.00299872
Diesel vehicle: 2000 – <3000 cc km 0.263537 0.25946 0.000389523 0.00368656
Diesel vehicle: ≥3000 cc km 0.292333 0.287811 0.000432085 0.00408938
Diesel hybrid vehicle: <1350 cc km 0.188407 0.185493 0.000278477 0.00263558
Diesel hybrid vehicle: 1350 – <1600 cc km 0.181306 0.178502 0.000267982 0.00253626
Diesel hybrid vehicle: 1600 – <2000 cc km 0.192164 0.189192 0.00028403 0.00268814
Diesel hybrid vehicle: 2000 – <3000 cc km 0.236242 0.232588 0.00034918 0.00330473
Diesel hybrid vehicle: ≥3000 cc km 0.262055 0.258002 0.000387334 0.00366584
Petrol vehicle: <1350 cc km 0.186651 0.178784 0.00238799 0.00547894
Petrol vehicle: 1350 – <1600 cc km 0.193174 0.185032 0.00247144 0.00567041
Petrol vehicle: 1600 – <2000 cc km 0.217508 0.208341 0.00278278 0.00638473
Petrol vehicle: 2000 – <3000 cc km 0.241592 0.23141 0.00309091 0.00709169
Petrol vehicle: ≥3000 cc km 0.289008 0.276827 0.00369753 0.00848352
Petrol hybrid vehicle: <1350 cc km 0.147356 0.141145 0.00188526 0.00432548
Petrol hybrid vehicle: 1350 – <1600 cc km 0.152505 0.146078 0.00195114 0.00447664
Petrol hybrid vehicle: 1600 – <2000 cc km 0.171717 0.16448 0.00219693 0.00504058
Petrol hybrid vehicle: 2000 – <3000 cc km 0.190731 0.182692 0.00244019 0.0055987
Petrol hybrid vehicle: ≥3000 cc km 0.228164 0.218547 0.00291911 0.00669751
Table 7.4: Vehicle fleet emission factors per km travelled, 2011–2015
Emissions Source Unit kg CO₂–e/unit CO₂/unit (kg CO₂–e) CH₄/unit (kg CO₂–e) N₂O/unit (kg CO₂–e)
2010–2015 Fleet
Motorcycle: <60cc, electricity km 0.00387074 0.00374625 0.000118451 0.00000604235
Motorcycle: <60cc, petrol km 0.0579353 0.0554934 0.000741218 0.00170063
Motorcycle: ≥ 60cc, electricity km 0.00774148 0.00749249 0.000236901 0.0000120847
Motorcycle: ≥ 60cc, petrol km 0.115871 0.110987 0.00148244 0.00340126
PHEV (Diesel) – Diesel consumption: <1350 cc km 0.087175 0.0858267 0.00012885 0.00121947
PHEV (Diesel) – Diesel consumption: 1350 – <1600 cc km 0.0838897 0.0825922 0.000123994 0.00117352
PHEV (Diesel) – Diesel consumption: 1600 – <2000 cc km 0.0889133 0.0875381 0.000131419 0.00124379
PHEV (Diesel) – Diesel consumption: 2000 – <3000 cc km 0.109308 0.107617 0.000161564 0.00152909
PHEV (Diesel) – Diesel consumption: ≥3000 cc km 0.121252 0.119376 0.000179218 0.00169617
Electric vehicle: <1350 cc km 0.0157241 0.0152184 0.000481181 0.0000245458
Electric vehicle: 1350 – <1600 cc km 0.0162736 0.0157502 0.000497997 0.0000254036
Electric vehicle: 1600 – <2000 cc km 0.0183236 0.0177343 0.000560731 0.0000286038
Electric vehicle: 2000 – <3000 cc km 0.0203526 0.019698 0.000622819 0.000031771
Electric vehicle: ≥3000 cc km 0.024347 0.0235639 0.000745055 0.0000380065
PHEV (Diesel) – Electricity consumption: <1350 cc km 0.00817485 0.00791193 0.000250163 0.0000127612
PHEV (Diesel) – Electricity consumption: 1350 – <1600 cc km 0.00785167 0.00759914 0.000240273 0.0000122567
PHEV (Diesel) – Electricity consumption: 1600 – <2000 cc km 0.008603 0.00832631 0.000263265 0.0000134296
PHEV (Diesel) – Electricity consumption: 2000 – <3000 cc km 0.00973735 0.00942417 0.000297978 0.0000152003
PHEV (Diesel) – Electricity consumption: ≥3000 cc km 0.0115167 0.0111463 0.00035243 0.000017978
PHEV (Petrol) – Electricity consumption: <1350 cc km 0.00749515 0.00725409 0.000229363 0.0000117002
PHEV (Petrol) – Electricity consumption: 1350 – <1600 cc km 0.00775708 0.00750759 0.000237378 0.0000121091
PHEV (Petrol) – Electricity consumption: 1600 – <2000 cc km 0.00873427 0.00845335 0.000267282 0.0000136345
PHEV (Petrol) – Electricity consumption: 2000 – <3000 cc km 0.00970138 0.00938936 0.000296877 0.0000151442
PHEV (Petrol) – Electricity consumption: ≥3000 cc km 0.0116054 0.0112321 0.000355143 0.0000181164
Diesel vehicle: <1350 cc km 0.186193 0.183313 0.000275205 0.00260462
Diesel vehicle: 1350 – <1600 cc km 0.179176 0.176405 0.000264833 0.00250646
Diesel vehicle: 1600 – <2000 cc km 0.189906 0.186969 0.000280692 0.00265655
Diesel vehicle: 2000 – <3000 cc km 0.233443 0.229832 0.000345042 0.00326558
Diesel vehicle: ≥3000 cc km 0.25895 0.254945 0.000382744 0.0036224
Diesel hybrid vehicle: <1350 cc km 0.166576 0.164 0.00024621 0.0023302
Diesel hybrid vehicle: 1350 – <1600 cc km 0.160299 0.157819 0.000236931 0.00224239
Diesel hybrid vehicle: 1600 – <2000 cc km 0.169898 0.16727 0.00025112 0.00237667
Diesel hybrid vehicle: 2000 – <3000 cc km 0.208869 0.205638 0.000308721 0.00292182
Diesel hybrid vehicle: ≥3000 cc km 0.231691 0.228108 0.000342454 0.00324108
Petrol vehicle: <1350 cc km 0.165024 0.158068 0.0021113 0.0048441
Petrol vehicle: 1350 – <1600 cc km 0.170791 0.163592 0.00218508 0.00501338
Petrol vehicle: 1600 – <2000 cc km 0.192306 0.184201 0.00246034 0.00564494
Petrol vehicle: 2000 – <3000 cc km 0.213599 0.204597 0.00273277 0.00626999
Petrol vehicle: ≥3000 cc km 0.255521 0.244751 0.00326911 0.00750054
Petrol hybrid vehicle: <1350 cc km 0.130282 0.124791 0.00166681 0.00382429
Petrol hybrid vehicle: 1350 – <1600 cc km 0.134835 0.129152 0.00172506 0.00395794
Petrol hybrid vehicle: 1600 – <2000 cc km 0.151821 0.145422 0.00194238 0.00445653
Petrol hybrid vehicle: 2000 – <3000 cc km 0.168631 0.161524 0.00215745 0.00494999
Petrol hybrid vehicle: ≥3000 cc km 0.201727 0.193225 0.00258087 0.00592148
PHEV (Petrol) – Petrol consumption: <1350 cc km 0.0681809 0.0653072 0.000872299 0.00200138
PHEV (Petrol) – Petrol consumption: 1350 – <1600 cc km 0.0705636 0.0675895 0.000902783 0.00207132
PHEV (Petrol) – Petrol consumption: 1600 – <2000 cc km 0.0794527 0.076104 0.00101651 0.00233225
PHEV (Petrol) – Petrol consumption: 2000 – <3000 cc km 0.0882503 0.0845307 0.00112906 0.00259049
PHEV (Petrol) – Petrol consumption: ≥3000 cc km 0.10557 0.101121 0.00135066 0.00309891
Table 7.5: Vehicle fleet emissions per km travelled, 2016−2020
Emissions Source Unit kg CO₂–e/unit CO₂/unit (kg CO₂–e) CH₄/unit (kg CO₂–e) N₂O/unit (kg CO₂–e)
2015–2020 Fleet
Motorcycle: <60cc, electricity km 0.0038091 0.00368659 0.000116564 0.00000594613
Motorcycle: <60cc, petrol km 0.0549576 0.0526413 0.000703122 0.00161322
Motorcycle: ≥ 60cc, electricity km 0.0076182 0.00737318 0.000233128 0.0000118923
Motorcycle: ≥ 60cc, petrol km 0.109915 0.105283 0.00140624 0.00322645
PHEV (Diesel) – Diesel consumption: <1350 cc km 0.0820636 0.0807944 0.000121295 0.00114797
PHEV (Diesel) – Diesel consumption: 1350 – <1600 cc km 0.078971 0.0777495 0.000116724 0.00110471
PHEV (Diesel) – Diesel consumption: 1600 – <2000 cc km 0.0837 0.0824055 0.000123714 0.00117086
PHEV (Diesel) – Diesel consumption: 2000 – <3000 cc km 0.102899 0.101307 0.000152091 0.00143943
PHEV (Diesel) – Diesel consumption: ≥3000 cc km 0.114142 0.112377 0.000168709 0.00159671
Electric vehicle: <1350 cc km 0.0150392 0.0145555 0.000460224 0.0000234768
Electric vehicle: 1350 – <1600 cc km 0.0155648 0.0150642 0.000476307 0.0000242972
Electric vehicle: 1600 – <2000 cc km 0.0175256 0.0169619 0.000536309 0.000027358
Electric vehicle: 2000 – <3000 cc km 0.0194661 0.01884 0.000595693 0.0000303873
Electric vehicle: ≥3000 cc km 0.0232866 0.0225376 0.000712604 0.0000363511
PHEV (Diesel) – Electricity consumption: <1350 cc km 0.0078188 0.00756733 0.000239267 0.0000122054
PHEV (Diesel) – Electricity consumption: 1350 – <1600 cc km 0.0075097 0.00726817 0.000229808 0.0000117229
PHEV (Diesel) – Electricity consumption: 1600 – <2000 cc km 0.0082283 0.00796366 0.000251799 0.0000128447
PHEV (Diesel) – Electricity consumption: 2000 – <3000 cc km 0.00931325 0.00901371 0.000285 0.0000145383
PHEV (Diesel) – Electricity consumption: ≥3000 cc km 0.0110151 0.0106609 0.00033708 0.000017195
PHEV (Petrol) – Electricity consumption: <1350 cc km 0.0071687 0.00693814 0.000219373 0.0000111906
PHEV (Petrol) – Electricity consumption: 1350 – <1600 cc km 0.00741922 0.0071806 0.00022704 0.0000115817
PHEV (Petrol) – Electricity consumption: 1600 – <2000 cc km 0.00835385 0.00808517 0.000255641 0.0000130406
PHEV (Petrol) – Electricity consumption: 2000 – <3000 cc km 0.00927885 0.00898042 0.000283947 0.0000144846
PHEV (Petrol) – Electricity consumption: ≥3000 cc km 0.0110999 0.0107429 0.000339675 0.0000173274
Diesel vehicle: <1350 cc km 0.176875 0.174139 0.000261432 0.00247427
Diesel vehicle: 1350 – <1600 cc km 0.170209 0.167577 0.000251579 0.00238102
Diesel vehicle: 1600 – <2000 cc km 0.180402 0.177612 0.000266645 0.0025236
Diesel vehicle: 2000 – <3000 cc km 0.221659 0.218231 0.000327626 0.00310074
Diesel vehicle: ≥3000 cc km 0.245879 0.242076 0.000363425 0.00343956
Diesel hybrid vehicle: <1350 cc km 0.156809 0.154384 0.000231774 0.00219357
Diesel hybrid vehicle: 1350 – <1600 cc km 0.1509 0.148566 0.000223039 0.00211091
Diesel hybrid vehicle: 1600 – <2000 cc km 0.159936 0.157463 0.000236396 0.00223732
Diesel hybrid vehicle: 2000 – <3000 cc km 0.196622 0.193581 0.000290619 0.0027505
Diesel hybrid vehicle: ≥3000 cc km 0.218107 0.214733 0.000322375 0.00305105
Petrol vehicle: <1350 cc km 0.155348 0.1488 0.00198751 0.00456008
Petrol vehicle: 1350 – <1600 cc km 0.160777 0.154 0.00205696 0.00471943
Petrol vehicle: 1600 – <2000 cc km 0.18103 0.1734 0.00231608 0.00531396
Petrol vehicle: 2000 – <3000 cc km 0.201075 0.1926 0.00257254 0.00590236
Petrol vehicle: ≥3000 cc km 0.240539 0.230401 0.00307743 0.00706076
Petrol hybrid vehicle: <1350 cc km 0.122643 0.117474 0.00156908 0.00360006
Petrol hybrid vehicle: 1350 – <1600 cc km 0.126929 0.121579 0.00162392 0.00372587
Petrol hybrid vehicle: 1600 – <2000 cc km 0.142919 0.136895 0.00182849 0.00419523
Petrol hybrid vehicle: 2000 – <3000 cc km 0.158744 0.152053 0.00203095 0.00465976
Petrol hybrid vehicle: ≥3000 cc km 0.189899 0.181895 0.00242955 0.00557429
PHEV (Petrol) – Petrol consumption: <1350 cc km 0.0641832 0.0614781 0.000821153 0.00188403
PHEV (Petrol) – Petrol consumption: 1350 – <1600 cc km 0.0664262 0.0636265 0.00084985 0.00194987
PHEV (Petrol) – Petrol consumption: 1600 – <2000 cc km 0.0747942 0.0716418 0.000956909 0.0021955
PHEV (Petrol) – Petrol consumption: 2000 – <3000 cc km 0.0830759 0.0795744 0.00106286 0.00243861
PHEV (Petrol) – Petrol consumption: ≥3000 cc km 0.0993805 0.0951918 0.00127146 0.00291721
Table 7.6: Post 2020 vehicle fleet emission factors per km travelled
Emissions Source Unit kg CO₂–e/unit CO₂/unit (kg CO₂–e) CH₄/unit (kg CO₂–e) N₂O/unit (kg CO₂–e)
Post 2020 Fleet
Motorcycle: <60cc, electricity km 0.00376922 0.003648 0.000115344 0.00000588388
Motorcycle: <60cc, petrol km 0.0527642 0.0505403 0.000675059 0.00154884
Motorcycle: ≥ 60cc, electricity km 0.00753845 0.00729599 0.000230688 0.0000117678
Motorcycle: ≥ 60cc, petrol km 0.105528 0.101081 0.00135012 0.00309767
PHEV (Diesel) – Diesel consumption: <1350 cc km 0.078307 0.0770958 0.000115742 0.00109542
PHEV (Diesel) – Diesel consumption: 1350 – <1600 cc km 0.0753559 0.0741904 0.000111381 0.00105414
PHEV (Diesel) – Diesel consumption: 1600 – <2000 cc km 0.0798685 0.0786331 0.00011805 0.00111726
PHEV (Diesel) – Diesel consumption: 2000 – <3000 cc km 0.0981884 0.0966698 0.000145128 0.00137354
PHEV (Diesel) – Diesel consumption: ≥3000 cc km 0.108917 0.107233 0.000160986 0.00152362
Electric vehicle: <1350 cc km 0.0145529 0.0140849 0.000445342 0.0000227176
Electric vehicle: 1350 – <1600 cc km 0.0150615 0.0145771 0.000460905 0.0000235115
Electric vehicle: 1600 – <2000 cc km 0.0169588 0.0164134 0.000518967 0.0000264733
Electric vehicle: 2000 – <3000 cc km 0.0188366 0.0182308 0.00057643 0.0000294046
Electric vehicle: ≥3000 cc km 0.0225336 0.0218088 0.000689561 0.0000351756
PHEV (Diesel) – Electricity consumption: <1350 cc km 0.00756597 0.00732263 0.00023153 0.0000118107
PHEV (Diesel) – Electricity consumption: 1350 – <1600 cc km 0.00726686 0.00703314 0.000222377 0.0000113438
PHEV (Diesel) – Electricity consumption: 1600 – <2000 cc km 0.00796223 0.00770614 0.000243656 0.0000124293
PHEV (Diesel) – Electricity consumption: 2000 – <3000 cc km 0.00901209 0.00872223 0.000275784 0.0000140682
PHEV (Diesel) – Electricity consumption: ≥3000 cc km 0.0106589 0.0103161 0.00032618 0.000016639
PHEV (Petrol) – Electricity consumption: <1350 cc km 0.00693689 0.00671378 0.000212279 0.0000108287
PHEV (Petrol) – Electricity consumption: 1350 – <1600 cc km 0.00717931 0.0069484 0.000219698 0.0000112071
PHEV (Petrol) – Electricity consumption: 1600 – <2000 cc km 0.00808372 0.00782372 0.000247374 0.000012619
PHEV (Petrol) – Electricity consumption: 2000 – <3000 cc km 0.0089788 0.00869002 0.000274765 0.0000140162
PHEV (Petrol) – Electricity consumption: ≥3000 cc km 0.010741 0.0103955 0.000328691 0.0000167671
Diesel vehicle: <1350 cc km 0.170089 0.167458 0.000251401 0.00237933
Diesel vehicle: 1350 – <1600 cc km 0.163679 0.161147 0.000241927 0.00228967
Diesel vehicle: 1600 – <2000 cc km 0.17348 0.170797 0.000256414 0.00242678
Diesel vehicle: 2000 – <3000 cc km 0.213111 0.209815 0.000314991 0.00298117
Diesel vehicle: ≥3000 cc km 0.236397 0.232741 0.00034941 0.00330691
Diesel hybrid vehicle: <1350 cc km 0.149631 0.147317 0.000221164 0.00209316
Diesel hybrid vehicle: 1350 – <1600 cc km 0.143992 0.141765 0.000212829 0.00201428
Diesel hybrid vehicle: 1600 – <2000 cc km 0.152615 0.150254 0.000225574 0.0021349
Diesel hybrid vehicle: 2000 – <3000 cc km 0.187621 0.184719 0.000277316 0.00262459
Diesel hybrid vehicle: ≥3000 cc km 0.208122 0.204903 0.000307617 0.00291138
Petrol vehicle: <1350 cc km 0.148057 0.141816 0.00189422 0.00434605
Petrol vehicle: 1350 – <1600 cc km 0.153231 0.146772 0.00196042 0.00449793
Petrol vehicle: 1600 – <2000 cc km 0.172534 0.165262 0.00220738 0.00506455
Petrol vehicle: 2000 – <3000 cc km 0.191638 0.183561 0.00245179 0.00562533
Petrol vehicle: ≥3000 cc km 0.229249 0.219587 0.00293299 0.00672937
Petrol hybrid vehicle: <1350 cc km 0.116745 0.111824 0.00149362 0.00342692
Petrol hybrid vehicle: 1350 – <1600 cc km 0.120825 0.115732 0.00154582 0.00354668
Petrol hybrid vehicle: 1600 – <2000 cc km 0.136045 0.130311 0.00174055 0.00399347
Petrol hybrid vehicle: 2000 – <3000 cc km 0.151109 0.14474 0.00193328 0.00443566
Petrol hybrid vehicle: ≥3000 cc km 0.180766 0.173147 0.0023127 0.00530621
PHEV (Petrol) – Petrol consumption: <1350 cc km 0.0610965 0.0585214 0.000781662 0.00179342
PHEV (Petrol) – Petrol consumption: 1350 – <1600 cc km 0.0632316 0.0605665 0.000808978 0.0018561
PHEV (Petrol) – Petrol consumption: 1600 – <2000 cc km 0.0711971 0.0681963 0.000910889 0.00208992
PHEV (Petrol) – Petrol consumption: 2000 – <3000 cc km 0.0790806 0.0757475 0.00101175 0.00232133
PHEV (Petrol) – Petrol consumption: ≥3000 cc km 0.094601 0.0906138 0.00121032 0.00277691
Table 7.7: Default private car emission factors per km travelled for default age of vehicle and <3000 cc engine size
Emissions Source Unit kg CO₂–e/unit CO₂/unit (kg CO₂–e) CH₄/unit (kg CO₂–e) N₂O/unit (kg CO₂–e)
Private car default
Diesel hybrid km 0.236242 0.232588 0.00034918 0.00330473
Diesel km 0.263537 0.25946 0.000389523 0.00368656
Petrol hybrid km 0.190731 0.182692 0.00244019 0.0055987
Petrol km 0.241592 0.23141 0.00309091 0.00709169
Electric km 0.0203526 0.019698 0.000622819 0.000031771
PHEV (Diesel) – Diesel consumption km 0.109308 0.107617 0.000161564 0.00152909
PHEV (Diesel) – Electricity consumption km 0.00973735 0.00942417 0.000297978 0.0000152003
PHEV (Petrol) – Electricity consumption km 0.00970138 0.00938936 0.000296877 0.0000151442
PHEV (Petrol) – Petrol consumption km 0.0882503 0.0845307 0.00112906 0.00259049

Note: Defaults are based on the average age of the vehicle fleet (pre-2010 for petrol and diesel including hybrids, and 2010–2015 for all plug-in cars) and most common engine size (2000–3000 cc). Source: Te Manatū Waka Ministry of Transport

Table 7.8: Default rental car emission factors per km travelled
Emissions Source Unit kg CO₂–e/unit CO₂/unit (kg CO₂–e) CH₄/unit (kg CO₂–e) N₂O/unit (kg CO₂–e)
Rental car default
Diesel hybrid km 0.159936 0.157463 0.000236396 0.00223732
Diesel km 0.180402 0.177612 0.000266645 0.0025236
Electric km 0.0175256 0.0169619 0.000536309 0.000027358
PHEV (Diesel) – Diesel consumption km 0.0837 0.0824055 0.000123714 0.00117086
PHEV (Diesel) – Electricity consumption km 0.0082283 0.00796366 0.000251799 0.0000128447
PHEV (Petrol) – Electricity consumption km 0.00835385 0.00808517 0.000255641 0.0000130406
PHEV (Petrol) – Petrol consumption km 0.0747942 0.0716418 0.000956909 0.0021955
Petrol hybrid km 0.142919 0.136895 0.00182849 0.00419523
Petrol km 0.18103 0.1734 0.00231608 0.00531396

Note: Defaults assume a 2015−2020 fleet for rental cars and engine size of 1600 – <2000 cc.

We were unable to source more up-to-date data on the New Zealand taxi fleet to produce a representative vehicle type for the taxi (regular) factor. Therefore, this factor is derived from an average of the factors for a petrol, diesel, petrol plug-in hybrid and electric vehicle, for a 2010−2015 fleet and 2000–3000 cc vehicle class.

Table 7.9: Emission factors for taxi travel
Emissions Source Unit kg CO₂–e/unit CO₂/unit (kg CO₂–e) CH₄/unit (kg CO₂–e) N₂O/unit (kg CO₂–e)
Taxi Travel
Regular – dollars spent $ 0.0406666 0.0393638 0.000374557 0.000928218
Electric – dollars spent $ 0.00520526 0.00503784 0.000159289 0.00000812558
Petrol hybrid – dollars spent $ 0.0431282 0.0413104 0.000551777 0.00126598
Regular km 0.159006 0.153913 0.00146452 0.00362933
Electric km 0.0203526 0.019698 0.000622819 0.000031771
Petrol hybrid km 0.168631 0.161524 0.00215745 0.00494999

7.2.1 GHG inventory development

Entities should gather the activity data on passenger vehicle use with as much detail as possible, including age of the vehicle, engine size, fuel type and kilometres travelled. If information is not available, we provide conservative defaults to allow for overestimation rather than underestimation.

If fuel-use data are available, see Section 3.3.

7.2.1.1 PASSENGER VEHICLES: EXAMPLE CALCULATION 1

An entity has 15 petrol vehicles. They use 40,000 litres of regular petrol in the reporting period.

Example calculation of standard private vehicle consumption
Gas Calculation Emissions (kg CO₂-e)
CO₂ emissions 40,000 x 2.2619 kg CO₂-e per litre 90,500 kg CO₂-e
CH₄ emissions 40,000 x 0.0302118 kg CO₂-e per litre 1,210 kg CO₂-e
N₂O emissions 40,000 x 0.0693172 kg CO₂-e per litre 2,770 kg CO₂-e
Total CO₂-e emissions 40,000 x 2.36143 kg CO₂-e per litre 94,500 kg CO₂-e

Note: Numbers may not add due to rounding.

If fuel-use data are not available, collect data on kilometres travelled by vehicle type and multiply this by the emission factor based on distance travelled for each GHG. If the vehicle is electric and the charging point is within the entity’s boundaries, this is a direct (Scope 1) emission source and emissions are zero. If travel is by rideshare apps (eg, Uber, YourRide, Waka Rider, Ola or Share Your Ride) we recommend using the taxi travel emission factors by distance travelled Table 7.9. If this information is not available, use the taxi emission factors per dollars spent.

Because plug-in hybrids operate on both a fossil fuel and electricity, two separate emission factors should be applied, that for the fossil fuel (petrol or diesel) and that for electricity. The plug-in hybrid electric vehicle electricity factor includes both the electricity and the electricity transmission and distribution loss factor.

Applying the equation E = Q x F this means:

  • E = emissions from the emissions source in kg CO2-e within the reporting period
  • Q = distance travelled by vehicle type (km)
  • F = emission factors for correlating vehicle type from Table 3.3 and Table 7.3 to Table 7.9

7.2.1.2 PASSENGER VEHICLES: EXAMPLE CALCULATION 2

An entity owns three post-2020 petrol plug-in hybrid electric vehicles (PHEVs). They are all between 1600 and 2000 cc and travel a total of 37,800 km in the reporting period. We need to capture both the fossil fuel and electricity-based emissions.

For the petrol-based emissions, use the PHEV (Petrol) − Petrol consumption emission factor:

Petrol component
Gas Calculation Emissions (kg CO₂-e)
CO₂ emissions 37,800 x 0.0681963 kg CO₂-e per km 2,580 kg CO₂-e
CH₄ emissions 37,800 x 0.000910889 kg CO₂-e per km 34.4 kg CO₂-e
N₂O emissions 37,800 x 0.00208992 kg CO₂-e per km 79.0 kg CO₂-e
Total CO₂-e emissions 37,800 x 0.0711971 kg CO₂-e per km 2,690 kg CO₂-e

Then also use the PHEV (Petrol) − Electricity consumption emission factor:

Electricity component
Gas Calculation Emissions (kg CO₂-e)
CO₂ emissions 37,800 x 0.00782372 kg CO₂-e per km 296 kg CO₂-e
CH₄ emissions 37,800 x 0.000247374 kg CO₂-e per km 9.35 kg CO₂-e
N₂O emissions 37,800 x 0.000012619 kg CO₂-e per km 0.477 kg CO₂-e
Total CO₂-e emissions 37,800 x 0.00808372 kg CO₂-e per km 306 kg CO₂-e

The sum of the above totals is the total emissions:

  • 2,690 kg CO₂-e + 306 kg CO₂-e = 3,000 kg CO₂-e

Note: Numbers may not add due to rounding.

7.2.1.3 PASSENGER VEHICLES: EXAMPLE CALCULATION 3

An entity uses petrol rental cars to travel 12,000 km. It also spends $18,000 on hybrid taxi travel.

  • Total CO2-e emissions from rental cars = 12,000 km × 0.18103 = 2,170 kg CO₂-e
  • Total CO2-e emissions from hybrid taxi travel = $18,000 × 0.0431282 = 776 kg CO₂-e

Note: Numbers may not add due to rounding.

7.2.2 Emission factor derivation methodology

The 2024 fleet statistics were taken from the Te Manatū Waka Ministry of Transport Vehicle Fleet Emissions Model. This provides energy (fuel and electricity) use per 100 km travelled by vehicle.

We split the fleet into four categories and develop average emission factors for these.

  • The pre-2010 fleet is based on the average fuel consumption data from 1970 to 2010. We assume there are no electric vehicles or plug-in hybrid vehicles.
  • The 2010–2015 fleet is based on the average fuel consumption data from vehicles produced between 2011 and 2015.
  • The 2015−2020 fleet is based on the average fuel consumption data from vehicles produced between 2016 and 2020.
  • The post-2020 fleet is based on the average fuel consumption data from vehicles produced from 2021 onwards.

Note that some guidance documents, such as those published by the UK Department for Energy Security and Net Zero (formerly published by the Department of Business, Energy and Industrial Strategy), apply an uplift factor to passenger vehicles. This accounts for the real-world effects on fuel consumption, such as the use of air conditioning, vehicle payload, gradient and weather. We do not apply an uplift factor here, because the Vehicle Fleet Emissions Model is based on real-world driving and fuel use.

For each category, default vehicles are based on the 2000–3000 cc engine size, as it is the most common size for light passenger vehicles in New Zealand based on Motor Vehicle Register open data.

Table 7.10: Fuel consumption in litres per 100 km
CC Unit Pre 2010 Fleet 2010-2015 Fleet 2015-2020 Fleet Post 2020 Fleet
Diesel hybrid vehicle
<1350 cc Litres 7.051748 6.234672 5.869113 5.600441
1350 - <1600 cc Litres 6.785994 5.99971 5.647928 5.389381
1600 - <2000 cc Litres 7.192363 6.358994 5.986146 5.712116
2000 - <3000 cc Litres 8.842125 7.8176 7.35923 7.022344
>=3000 cc Litres 9.808287 8.671815 8.163359 7.789662
Diesel vehicle
<1350 cc Litres 7.866491 6.968889 6.620127 6.366127
1350 - <1600 cc Litres 7.570033 6.706258 6.370639 6.126212
1600 - <2000 cc Litres 8.023353 7.107853 6.752135 6.493071
2000 - <3000 cc Litres 9.863725 8.737359 8.296327 7.976384
>=3000 cc Litres 10.941516 9.692074 9.202851 8.847949
Electric vehicle
<1350 cc kWh 20.969073 18.582306 17.772969 17.198247
1350 - <1600 cc kWh 21.701863 19.231687 18.394067 17.799261
1600 - <2000 cc kWh 24.435734 21.65438 20.711242 20.041506
2000 - <3000 cc kWh 27.141421 24.052097 23.004528 22.260634
>=3000 cc kWh 32.468242 28.772602 27.519435 26.629544
Motorcycle
<60cc, electricity Litres 5.125548 4.574334 4.50149 4.454366
<60cc, petrol Litres 2.77416 2.453401 2.327306 2.234419
>=60cc, electricity Litres 10.251095 9.148669 9.00298 8.908733
>=60cc, petrol Litres 5.54832 4.906803 4.654612 4.468839
PHEV (Diesel) - Diesel consumption
<1350 cc Litres 3.690415 3.262811 3.071503 2.930897
1350 - <1600 cc Litres 3.551337 3.139848 2.955749 2.820443
1600 - <2000 cc Litres 3.764003 3.327874 3.13275 2.989341
2000 - <3000 cc Litres 4.627379 4.091211 3.85133 3.675027
>=3000 cc Litres 5.133004 4.53825 4.272158 4.07659
PHEV (Diesel) - Electricity consumption
<1350 cc kWh 10.901683 9.660818 9.240049 8.941255
1350 - <1600 cc kWh 10.470705 9.278895 8.874761 8.587779
1600 - <2000 cc kWh 11.472649 10.166795 9.723988 9.409545
2000 - <3000 cc kWh 12.985372 11.507335 11.006143 10.650239
>=3000 cc kWh 15.358305 13.610174 13.017394 12.596452
PHEV (Petrol) - Electricity consumption
<1350 cc kWh 9.995258 8.857566 8.471782 8.197831
1350 - <1600 cc kWh 10.344555 9.167104 8.767839 8.484314
1600 - <2000 cc kWh 11.6477 10.321921 9.872359 9.553118
2000 - <3000 cc kWh 12.937411 11.464833 10.965492 10.610902
>=3000 cc kWh 15.476529 13.71494 13.117597 12.693416
PHEV (Petrol) - Petrol consumption
<1350 cc Litres 3.265663 2.887276 2.717986 2.587271
1350 - <1600 cc Litres 3.379786 2.988175 2.812969 2.677686
1600 - <2000 cc Litres 3.805551 3.364607 3.16733 3.015005
2000 - <3000 cc Litres 4.226927 3.737159 3.518038 3.348846
>=3000 cc Litres 5.056511 4.47062 4.208494 4.006097
Petrol hybrid vehicle
<1350 cc Litres 6.240121 5.517087 5.193603 4.94383
1350 - <1600 cc Litres 6.45819 5.709889 5.3751 5.116598
1600 - <2000 cc Litres 7.271754 6.429186 6.052223 5.761156
2000 - <3000 cc Litres 8.076931 7.141069 6.722365 6.39907
>=3000 cc Litres 9.662123 8.542587 8.041708 7.654962
Petrol vehicle
<1350 cc Litres 7.904154 6.98831 6.578564 6.269797
1350 - <1600 cc Litres 8.180374 7.232526 6.80846 6.488903
1600 - <2000 cc Litres 9.210889 8.143636 7.666149 7.306336
2000 - <3000 cc Litres 10.230779 9.045353 8.514996 8.115342
>=3000 cc Litres 12.238689 10.82061 10.186163 9.708073
Source: Te Manatū Waka Ministry of Transport Vehicle Fleet Emissions Model

Vehicle emissions per kilometre are calculated by combining real-world fuel consumption with fuel-specific emission factors expressed in carbon dioxide equivalent (CO₂-e):

\[ \begin{aligned} \text{emissions per km}~(\mathrm{kg~CO_2\text{-}e~km^{-1}}) &= \frac{C \times F}{100} \end{aligned} \]

Where:

  • C = fuel consumption (L per 100 km)
  • F = fuel emission factor (kg CO2-e L-1)

Dividing by 100 gives a factor for litres (or kWh) per fuel per km. Use this with the fuel emission factors to calculate emissions per km.

Multiply the values for fuel consumption by the emission conversion factors in Table 3.3.

New Zealand Transport Agency vehicle registration data is unchanged from the 2022 guidance, where the average year of manufacture for the taxi fleet was 2012, and 2015 for the rental fleet1. We assumed a 2010–2015 fleet for taxis and post-2015 fleet for rental cars.

The taxi (regular) factor is derived from an average of the factors for a petrol, diesel, petrol plug-in hybrid and electric vehicle, for a 2000–3000 cc vehicle class. These workings are in Table 7.11.

Table 7.11: Data used for calculating the taxi (regular) emission factor
Vehicle CC Unit CO₂/unit (kg CO₂-e) CH₄/unit (kg CO₂-e) N₂O/unit (kg CO₂-e) Total kg CO₂-e/unit
Electric 2000 - <3000 cc km 0.019698 0.000623 0.000032 0.020353
Diesel 2000 - <3000 cc km 0.229832 0.000345 0.003266 0.233443
Petrol 2000 - <3000 cc km 0.204597 0.002733 0.00627 0.213599
Petrol hybrid 2000 - <3000 cc km 0.161524 0.002157 0.00495 0.168631
Taxi (regular) Average km 0.153913 0.001465 0.003629 0.159006

As of March 2026, TaxiCharge NZ Ltd advised that the average price per kilometre in a taxi is $3.91. North Island’s average rate = $3.8, while South Island’s average = $4.13.

The calculation to develop the emission factors for taxi based by $ spend is:

\[ \begin{aligned} \text{emissions per \$ spend} &= \frac{ \text{emissions per km} }{ \text{average price per km} } \end{aligned} \]

The private car default is based on the average age of light passenger vehicles in the New Zealand fleet, back-calculated to the year of manufacture, with the fuel consumption factors in Table 7.12 applied.

According to Te Manatū Waka Ministry of Transport’s The New Zealand 2024 Vehicle Fleet: Data Spreadsheet2, the average age of light passenger vehicles is 17 years.

Table 7.12: Energy consumption per 100 km for average light passenger vehicles
Engine type Unit Units per 100 km for a 2000–3000 cc engine
Petrol Litres 10.230779
Diesel Litres 9.863725
Petrol hybrid Litres 8.076931
Diesel hybrid Litres 8.842125
PHEV (Petrol) - Petrol consumption Litres 3.737159
PHEV (Petrol) - Electricity consumption kWh 11.464833
PHEV (Diesel) - Diesel consumption Litres 4.091211
PHEV (Diesel) - Electricity consumption kWh 11.507335
Electric kWh 24.052097

The default emission factor for rental cars is the same as for vehicles in the post-2015 fleet, 1600–2000 cc category.

7.2.3 Assumptions, limitations and uncertainties

Emission factors from fuel are multiplied by real-world consumption rates for vehicles with different engine sizes. The uncertainties embodied in these figures carry through to the emission factors. For petrol vehicles, we multiplied the real-world consumption by ‘regular petrol’ emission factors from the fuel emission source category. This may overestimate emissions for some and underestimate emissions for others.

According to Te Manatū Waka Ministry of Transport’s The New Zealand 2024 Vehicle Fleet: Data Spreadsheet3, the most common size of light passenger vehicle is between 2000 cc and 3000 cc. Therefore, the default emission factors (for vehicles of unknown engine size) are the same as for a <3000 cc vehicle.

The Vehicle Fleet Emissions Model contains uncertainties about the fuel consumption figures provided. Emission factors represent the average fuel consumption of vehicles operating in the real world under different driving conditions, across all vehicle types in that classification.

We assume there are no fully electric vehicles nor PHEVs in New Zealand in the pre-2010 fleet.

7.3 Public transport passenger travel

The emission factors for public transport for passenger travel on buses, trains and a ferry were provided by Auckland Transport. The unit used for these emission sources are passenger kilometres (pkm).

The national average for the bus factor is unchanged from the previous edition.

Table 7.13: Emission factors for public transport
Emissions Source Unit kg CO₂–e/unit CO₂/unit (kg CO₂–e) CH₄/unit (kg CO₂–e) N₂O/unit (kg CO₂–e)
Bus
National Average for Bus pkm 0.15525 0.153 0.000125 0.002125
Diesel Bus pkm 0.168496 0.16589 0.000249048 0.00235706
Hydrogen Bus pkm 0.0332677 0.0324063 0.000808818 0.0000526118
Electric Bus pkm 0.0175734 0.0171104 0.000434797 0.0000281847
Average Bus pkm 0.144925 0.142654 0.000278103 0.00199331
Ferry
Ferry Average pkm 0.661724 0.651489 0.000978068 0.00925671
Rail
Metropolitan Diesel pkm 0.273943 0.269706 0.000404905 0.00383213
Metropolitan Electric pkm 0.0204306 0.019871 0.000522958 0.0000366631
Metropolitan Average pkm 0.0270397 0.0263842 0.00051988 0.000135611

7.3.1 GHG inventory development

To calculate public transport passenger emissions, collect data on the type of transport and distance travelled, and multiply this by the emission factors for each gas. Entities could conduct a staff travel survey to quantify these emissions.4

Applying the equation E = Q x F this means:

  • E = emissions from the emissions source in kg CO2-e within the reporting period
  • Q = distance travelled, by vehicle type (km)
  • F = emission factors for correlating vehicle type, from Table 7.13.

7.3.1.1 PASSENGER BUS: EXAMPLE CALCULATION

An employee takes a return trip on an electric Wellington bus from the CBD to the airport (9.4 km each way). This happens five times in the reporting year.

Passenger kilometres travelled = 2 trips × 9.4 km x 5 times = 94 pkm

Gas Calculation Emissions (kg CO₂-e)
CO₂ emissions 94 x 0.0171104 kg CO₂-e per pkm 1.61 kg CO₂-e
CH₄ emissions 94 x 0.000434797 kg CO₂-e per pkm 0.0409 kg CO₂-e
N₂O emissions 94 x 0.0000281847 kg CO₂-e per pkm 0.00265 kg CO₂-e
Total CO₂-e emissions 94 x 0.0175734 kg CO₂-e per pkm 1.65 kg CO₂-e

Note: Numbers may not add due to rounding.

7.3.2 Emission factor derivation methodology

7.3.2.1 National average bus

To calculate the emission factor for national average bus travel we used the New Zealand Transport Agency passenger travel data Table 7.14 to estimate the national average loading capacity of seven people per bus.

Table 7.14: National bus passenger kilometres in 2020/21
Region Mode Breakdown 2020/21
New Zealand Bus pkm 534,976,704
New Zealand Bus Service km 122,934,050

The passenger loading per bus for the different regions for 2020/21 is shown in Table 7.15.

Table 7.15: National bus passenger loading by region
Region Unit End Use
National average Passenger/bus 7
Auckland Passenger/bus 7
Bay of Plenty Passenger/bus 3
Canterbury Passenger/bus Missing data
Gisborne Passenger/bus 8
Hawkes Bay Passenger/bus 1
Manawatū-Whanganui Passenger/bus 5
Marlborough-Nelson-Tasman Passenger/bus 6
Northland Passenger/bus 8
Otago Passenger/bus Missing data
Southland Passenger/bus 3
Taranaki Passenger/bus 12
Waikato Passenger/bus 4
Wellington Passenger/bus 20

We then divided the per kilometre emission factor for diesel buses in Table 7.14 by the national passenger/bus loading rate to give the emissions per gas, see Table 7.22.

Table 7.16: Emission factor for national average bus
Emissions Source Unit kg CO₂–e/unit CO₂/unit (kg CO₂–e) CH₄/unit (kg CO₂–e) N₂O/unit (kg CO₂–e)
Public Transport Vehicle
Diesel bus: ≥ 12000 kg km 1.07809 1.06142 0.00159348 0.0150812

7.3.2.2 Auckland buses

To calculate the emissions from Auckland buses we used the most recent data available, which were from the year 2024. This information was from Auckland Transport.

Data for the electric and hydrogen buses are in Table 7.17. The distance travelled by electric and hydrogen buses for each 2024/25 quarter was multiplied by an estimated average power consumption rate shown below. The resultant energy consumption was multiplied by its respective quarterly electricity emission factor (including the transmission and distribution loss factor of electricity) to produce quarterly emissions totals. These totals were then divided by the quarterly totals for passenger kilometres travelled. The final emission factor is weighted based on the quarterly emissions totals and quarterly passenger kilometres travelled.

Table 7.17: Auckland Transport 2024/25 data for electric and hydrogen buses
Bus type Fiscal year quarter Distance (km) Fuel consumption rate (kWh/km) Electricity consumption pkm
Electric Q1 2,585,564.698 1.122419 2,902,087.022917 17,070,062.02
Electric Q2 2,429,012.282 1.122419 2,726,369.61185 15,181,197.15
Electric Q3 2,572,202.332 1.122419 2,887,088.849019 18,141,945.12
Electric Q4 3,141,570.894 1.122419 3,526,158.958661 21,908,441.06
Hydrogen Q1 796.732 4.598356 3,663.657542 12,959.41187
Hydrogen Q2 2,930.356 4.598356 13,474.820719 40,586.57239
Hydrogen Q3 0 4.598356 0 0
Hydrogen Q4 0 4.598356 0 0

Data for the diesel buses are in Table 7.18. The annual distance travelled was multiplied by an estimated fuel efficiency as shown below. The resultant energy consumption was multiplied by the diesel emission factor, to produce an annual emissions total. This total was then divided by the annual passenger kilometres travelled, to produce the final emission factor.

Table 7.18: Auckland Transport 2024/25 data for diesel buses
Distance (km) Fuel consumption rate (l/km) Fuel consumption (litres) pkm
57,223,645.75 0.430796 24,651,713.688862 390,892,165

7.3.2.3 Auckland trains

To calculate the emissions from Auckland trains we used the most recent data available, which were from the year 2023/24 for electric trains. Diesel trains stopped operating in the region in August 2022. This information was from Auckland Transport.

Data for the electric and diesel trains are in Table 7.19. The diesel fuel used by diesel trains was multiplied by the diesel emission factor in Table 3.3 to produce an annual emissions total. This total was then divided by the annual passenger kilometres travelled, to produce the final emission factor.

The electricity used by electric trains for each year quarter, was multiplied by the respective quarterly electricity emission factors (including the transmission and distribution loss factor of electricity) to produce quarterly emissions totals. These totals were then divided by the quarterly totals for passenger kilometres travelled. The final emission factor is weighted based on the quarterly emissions totals and quarterly passenger kilometres travelled.

The diesel fuel used by diesel trains was multiplied by the diesel emission factor (in Table 3.3) to produce an annual emissions total. This total was then divided by the annual passenger kilometres travelled, to produce the final emission factor.

Table 7.19: Auckland train data
Train type Quarter/Year Unit Fuel consumption per unit pkm
Electric Sep-24 kWh 8,464,503 45,416,453.79
Electric Dec-24 kWh 8,720,137 40,995,395.85
Electric Mar-25 kWh 7,504,455 35,364,331.33
Electric Jun-25 kWh 6,903,715 39,996,117.23
Diesel 2021/22 Litres 443,997 4,330,313

The train average factor is weighted based on the emission factors for electric and diesel trains and the respective passenger kilometres travelled.

7.3.3 Auckland ferry

To calculate the emissions from ferry travel we used the 2024 data provided by Auckland Transport.

We multiplying the annual fuel consumption to the diesel emission factor (in Table 3.3) to produce an annual emissions total. This total was then divided by the annual passenger kilometres travelled.

Table 7.20: Ferry data
Distance Fuel consumption (litres) pkm
950,075 5,003,815 20,203,403

7.3.4 Assumptions, limitations and uncertainties

Limited data are available for areas outside the Auckland region.

These metro commuter rail emission factors are assumed to be appropriate for use on any commuter rail line in New Zealand.

7.4 Public transport vehicles

Public transport vehicle emissions include those from buses. Emissions are calculated for the whole vehicle. This approach is appropriate for transport operators or if a bus is chartered. Table 7.21 details these emission factors.

Buses: We calculated the emissions of different buses using Te Manatū Waka Ministry of Transport Vehicle Fleet Emissions Model data for fuel consumption in litres per 100 kilometres. The guide presents the data in emissions per kilometre.

The change in all-electric and PHEV vehicle emission factors is driven by the increase in the latest annual electricity factor, which is used to derive these emission factors.

Table 7.21 details the data provided to calculate the emission conversion factors.

Table 7.21: Bus emission factors per km travelled
Emissions Source Unit kg CO₂–e/unit CO₂/unit (kg CO₂–e) CH₄/unit (kg CO₂–e) N₂O/unit (kg CO₂–e)
Public Transport Vehicle
Diesel bus: < 7500 kg km 0.561585 0.5529 0.000830057 0.0078559
Diesel bus: 7500 – 12000 kg km 0.777864 0.765833 0.00114973 0.0108814
Diesel bus: ≥ 12000 kg km 1.07809 1.06142 0.00159348 0.0150812
Diesel hybrid bus: < 7500 kg km 0.397405 0.391258 0.000587389 0.00555921
Diesel hybrid bus: 7500 – 12000 kg km 0.550454 0.541941 0.000813605 0.00770019
Diesel hybrid bus: ≥ 12000 kg km 0.762909 0.75111 0.00112763 0.0106722
Electric bus: < 7500 kg km 0.048816 0.047246 0.00149385 0.0000762035
Electric bus: 7500 – 12000 kg km 0.0676162 0.0654414 0.00206916 0.000105551
Electric bus: ≥ 12000 kg km 0.0937135 0.0906994 0.00286778 0.00014629

7.4.1 GHG inventory development

To calculate public transport emissions, collect data on the type of transport and distance travelled, and multiply this by the emission factors for each gas.

Applying the equation E = Q x F this means:

  • E = emissions from the emissions source in kg CO2-e within the reporting period
  • Q = distance travelled, by vehicle type (km)
  • F = emission factors for correlating vehicle type, from Table 7.21.

7.4.1.1 DIESEL BUS: EXAMPLE CALCULATION

An entity charters a diesel bus (<7,500 kg) to travel 500 km. The emissions would be:

Gas Calculation Emissions (kg CO₂-e)
CO₂ emissions 500 x 0.5529 kg CO₂-e per km 276 kg CO₂-e
CH₄ emissions 500 x 0.000830057 kg CO₂-e per km 0.415 kg CO₂-e
N₂O emissions 500 x 0.0078559 kg CO₂-e per km 3.93 kg CO₂-e
Total CO₂-e emissions 500 x 0.561585 kg CO₂-e per km 281 kg CO₂-e

This result is for the entire bus.

Note: Numbers may not add due to rounding.

7.4.2 Emission factor derivation methodology

The average age of the bus fleet is 18 years according to Te Manatū Waka Ministry of Transport’s The New Zealand 2024 Vehicle Fleet: Data Spreadsheet5. Therefore, we applied an average fuel consumption factor for a pre-2010 fleet to the bus fleet from the Vehicle Fleet Emissions Model.

Table 7.22: Fuel/energy consumption per 100 km for pre-2010 fleet buses
Emission source Weight class Unit Pre-2010 units of energy per 100 km
Diesel bus <7500 kg Litre 21.01919
7500 - 12000 kg Litre 29.114137
>=12000 kg Litre 40.351124
Diesel hybrid bus <7500 kg Litre 14.874195
7500 - 12000 kg Litre 20.60257
>=12000 kg Litre 28.554405
Electric bus <7500 kg kWh 57.689474
7500 - 12000 kg kWh 79.906944
>=12000 kg kWh 110.748089

Using the information in Table 7.22 and appropriate emission factor, the equation is:

\[ \mathrm{Emissions\ per\ km}\,(\mathrm{kg\ CO_2\text{-}e\ km^{-1}}) = \frac{ \mathrm{Energy\ use}\,(\mathrm{unit\ per\ 100\ km}) \times \mathrm{Emission\ factor}\,(\mathrm{kg\ CO_2\text{-}e\ unit^{-1}}) }{ 100 } \]

Where:

  • fuel/energy consumption = units of energy per 100 km travelled (L for diesel/hybrid and kWh for electric)
  • emission factor = the emission factor from Table 3.3 or Table 5.2

This allows you to use distance travelled as a unit for calculating emissions. If there are data on the quantity of fuel used, refer to transport fuel emission factors.

7.4.3 Assumptions, limitations and uncertainties

The Vehicle Fleet Emissions Model historical year results have been carefully calibrated to give a total road fuel use that matches MBIE’s road fuel sales figures. The sources used to develop these emission factors will have inbuilt assumptions, limitations and uncertainties. To investigate these, see the documents referenced.

7.5 Air travel

This section covers emission factors for domestic and international air travel for entities seeking to determine the emissions from business travel.

7.5.1 Domestic air travel

This section provides emission factors based on data from 2024. Domestic air travel is a common source of indirect (Scope 3) emissions for many New Zealand entities.

For air travel emission factors, multipliers or other corrections may be applied to account for the radiative forcing of emissions arising from aircraft transport at high altitude (jet aircraft). Radiative forcing helps entities account for the wider climate effects of aviation, including water vapour and indirect GHGs. This is an area of active research and uncertainty, aiming to express the relationship between emissions and the climate warming effects of aviation, but there is yet to be consensus on this aspect.

In this guidance, emission factors with a radiative forcing multiplier refers to the indirect climate change effects (non-CO₂ emissions eg, water vapour, contrails, NOx). Emission factors without a radiative forcing multiplier refers to the direct climate change effects (CO₂, CH₄ and N₂O). If multipliers are applied, entities should disclose the specific factor used including its source and produce comparable reporting. Therefore, avoid reporting with air travel conversion factors in one year and without in another year, as this may skew the interpretation of your reporting.

The decision to apply the Radiative Forcing Index, and to what type of air travel (flight altitude) should be guided by the requirements of your intended use and users.

In terms of the small and medium aircraft, a radiative forcing multiplier may not be required given the lower altitude at which these aircrafts typically fly. However, these emission factors are provided in the tables below for completeness, and for users wanting to take a conservative approach to their reporting.

Table 7.23 provides the emission factors without the radiative forcing multiplier applied. Table 7.24 provides emission factors with a radiative forcing multiplier of 1.7 applied.

Table 7.23: Domestic air travel emission factors without a radiative forcing multiplier
Emissions Source Unit kg CO₂–e/unit CO₂/unit (kg CO₂–e) CH₄/unit (kg CO₂–e) N₂O/unit (kg CO₂–e)
Without Radiative Forcing factors
National average pkm 0.115861 0.114987 0.00002251 0.00085224
Large aircraft pkm 0.104803 0.104012 0.00002036 0.00077089
Medium aircraft pkm 0.121068 0.120154 0.00002352 0.00089053
Small aircraft pkm 0.352462 0.340537 0.0028842 0.0090416
Table 7.24: Domestic air travel emission factors with a radiative forcing multiplier
Emissions Source Unit kg CO₂–e/unit CO₂/unit (kg CO₂–e) CH₄/unit (kg CO₂–e) N₂O/unit (kg CO₂–e)
With Radiative Forcing factors
National average pkm 0.196964 0.195477 0.0000383 0.0014488
Large aircraft pkm 0.178165 0.17682 0.0000346 0.00131052
Medium aircraft pkm 0.205816 0.204262 0.00004 0.00151391
Small aircraft pkm 0.590838 0.578912 0.0028842 0.0090416

We have provided a national average emission factor, and three factors based on the aircraft size: large, medium or small aircraft. A large aircraft in New Zealand would be an Airbus A320neo, A320ceo and A321neo. A medium aircraft has between 50 and 70 seats (ie, regional services on an ATR 72 or de Havilland Q300) and a small aircraft has fewer than 50 seats. If the aircraft type is unknown, we recommend using the national average.

7.5.1.1 GHG inventory development

To calculate emissions for domestic air travel, collect information on passengers flying, their departure and destination airports, flight length, travel class and, if practical, the type of aircraft. Your travel provider may be able to provide this information.

If the type of aircraft is unknown, use the national average emission factors. Calculate distances using online calculators such as www.airmilescalculator.com. Multiply the number of passengers by the distance travelled to obtain the pkm.

Applying the equation E = Q x F this means:

  • E = emissions from the emissions source in kg CO2-e within the reporting period
  • Q = passengers multiplied by distance flown (pkm)
  • F = emission factors from Table 7.23 to Table 7.24
DOMESTIC AIR TRAVEL: EXAMPLE CALCULATION

An entity flies an employee on a return flight from Christchurch to Wellington (304 km each way). This happens five times in the reporting year on an aircraft of unknown size. The national average emission factor with radiative forcing is used.

Passenger kilometres travelled = (2 × 304) × 5 = 3,040 pkm

Gas Calculation Emissions (kg CO₂-e)
CO₂ emissions 3,040 x 0.195477 kg CO₂-e per pkm 594 kg CO₂-e
CH₄ emissions 3,040 x 0.0000383 kg CO₂-e per pkm 0.116 kg CO₂-e
N₂O emissions 3,040 x 0.0014488 kg CO₂-e per pkm 4.40 kg CO₂-e
Total CO₂-e emissions 3,040 x 0.196964 kg CO₂-e per pkm 599 kg CO₂-e

Note: Numbers may not add due to rounding.

7.5.1.2 Emission factor derivation methodology

We developed emission factors for aircraft type with data supplied by Air New Zealand and Te Manatū Waka Ministry of Transport. We calculated an average emission factor for domestic air travel using data from the 2016, 2020 and 2023 calendar years. Table 7.25 details the types of aircraft running domestic flights, using Air New Zealand data and 2016 Te Manatū Waka Ministry of Transport data to calculate the emission factors.

An average emission factor has also been provided where the aircraft type is unknown (see Table 7.23 and Table 7.24). Entities that own aircraft could calculate emissions based on the fuel consumption data.

Table 7.25: Domestic aviation data (2016, 2020 and 2023)
Aircraft type Total seats per flight Average distance per flight (km) Total fuel used (kg) Total flights
Airbus A320 173 666.15 158,788,876.5 49,699
Aerospatiale/Alenia ATR 72 68 399.11 39,631,695.18 51,267
British Aerospace Jetstream 32 19 167.78 94,556 324
Beechcraft Beech 1900D 19 250.73 2,152,521.4 6,277
Cessna Light Aircraft 6 95.87 1,199,632.3 9,791
De Havilland Canada DHC-8-300 Dash 8/8Q 50 313.25 61,505,087.49 71,122
Pilatus PC-12 9 300.72 847,901.49 4,315
Saab SF-340 34 479.7 407,373.7 668
FOKKER F50 53 631.55 12,890.19 11
Note: Average calculated using data from 2016, 2020 and 2023.

To calculate the emission factor, first calculate average fuel (kg) per flight for each aircraft:

\[ \begin{aligned} \frac{ \text{average total fuel used (kg)} }{ \text{average number of flights} } \end{aligned} \]

Then calculate average fuel (kg) per passenger:

\[ \begin{aligned} \frac{ \text{average total fuel (kg) per flight} }{ \text{average number of seats} \times 0.8 } \end{aligned} \]

Using this, next calculate fuel per passenger per km:

\[ \begin{aligned} \frac{ \text{average fuel (kg) per passenger} }{ \text{average flight distance (km)} } \end{aligned} \]

The density of kerosene (the assumed aviation fuel) is 0.79 kg/l.6

Emission factors for each aircraft were determined by multiplying the fuel (litres) per passenger per kilometre by the kerosene (aviation fuel) emission factor in Table 3.3

Table 7.26: Calculated emissions, without the radiative forcing multiplier, per aircraft type
Emissions Source Unit kg CO₂–e/unit CO₂/unit (kg CO₂–e) CH₄/unit (kg CO₂–e) N₂O/unit (kg CO₂–e) Uncertainties
Without radiative forcing factors
Aerospatiale/Alenia ATR 72 pkm 0.113548 0.112691 0.0000220611 0.000835171
Airbus A320 pkm 0.110518 0.109683 0.0000214723 0.00081288
Beechcraft Beech 1900D pkm 0.179088 0.177736 0.0000347948 0.00131723
British Aerospace Jetstream 32 pkm 0.227762 0.226043 0.0000442516 0.00167524
Cessna Light Aircraft pkm 0.52993 0.525929 0.000102959 0.00389774
De Havilland Canada DHC–8–300 Dash 8/8Q pkm 0.220102 0.21844 0.0000427632 0.00161889
FOKKER F50 pkm 0.0870993 0.0864417 0.0000169224 0.000640633
Pilatus PC–12 pkm 0.180631 0.179267 0.0000350944 0.00132857
Saab SF–340 pkm 0.0930249 0.0923226 0.0000180737 0.000684217

Note: 2016 or 2020 data unless denoted otherwise. Airbus A320, Aerospatiale/Alenia ATR 72, De Havilland Q300 updated using 2023 data.

Table 7.27: Calculated emissions, with the radiative forcing multiplier, per aircraft type
Emissions Source Unit kg CO₂–e/unit CO₂/unit (kg CO₂–e) CH₄/unit (kg CO₂–e) N₂O/unit (kg CO₂–e) Uncertainties
With radiative forcing factors
Aerospatiale/Alenia ATR 72 pkm 0.192432 0.191575 0.0000220611 0.000835171
Airbus A320 pkm 0.187296 0.186462 0.0000214723 0.00081288
Beechcraft Beech 1900D pkm 0.303503 0.302151 0.0000347948 0.00131723
British Aerospace Jetstream 32 pkm 0.385992 0.384273 0.0000442516 0.00167524
Cessna Light Aircraft pkm 0.898081 0.89408 0.000102959 0.00389774
De Havilland Canada DHC–8–300 Dash 8/8Q pkm 0.37301 0.371348 0.0000427632 0.00161889
FOKKER F50 pkm 0.147608 0.146951 0.0000169224 0.000640633
Pilatus PC–12 pkm 0.306117 0.304754 0.0000350944 0.00132857
Saab SF–340 pkm 0.157651 0.156948 0.0000180737 0.000684217

Note: 2016 or 2020 data unless denoted otherwise. Airbus A320, Aerospatiale/Alenia ATR 72 using 2023 data.

For situations where the aircraft type is unknown, average emission factors are also provided for a domestic average, and for large, medium and small aircraft (see Table 7.23 and Table 7.24).

We then calculated a weighted average emission factor for each size category, using the aircraft types within that size range. The weighted averages are calculated using the annual flight domestic distance travelled and the total number of domestic flights for each aircraft type. This method applies an equal weighting of 50 per cent to both distance travelled and number of flights.

  • Large aircraft: A320neo, A320ceo and A321neo
  • Medium aircraft: ATR 72 and Q300
  • Small aircraft: British Aerospace Jetstream 32, Cessna Light Aircraft.

A national average emission factor was calculated using the same weighted average approach described above, this time considering the contribution each of the five large and medium aircraft types make to the overall distance travelled and number of flights.

7.5.1.3 Assumptions, limitations and uncertainties

We assume the fuel for domestic flights is kerosene (aviation fuel) and all the kerosene is combusted. The domestic emission factors are based on fuel delivery data. Therefore, it is not necessary to apply a distance uplift factor to account for delays/circling and non-direct routes (ie, not along the straight-line/great-circle between destinations). However, this should be considered for international air travel.

7.5.2 International air travel

The International air travel emission factors are sourced from the UK Greenhouse Gas Reporting: Conversion Factors 2025, published by the UK Department for Energy Security and Net Zero (DESNZ).

Entities wishing to report their international air travel emissions based on distance travelled per passenger could use the International Civil Aviation Organisation (ICAO) calculator. This calculator considers aircraft types and load factors for specific airline routes but does not apply the radiative forcing multiplier (accounting for the wider climate effect of emissions arising from aircraft transport at altitude) or distance uplift factor to account for delays/circling and non-direct routes (ie, not along the straight-line/great-circle between destinations). If using the ICAO calculator to calculate emissions for international air travel, multiply the output by 1.08 to account for the 8 per cent distance uplift factor (see Section 7.5.2.3) and then by 1.7 to apply a radiative forcing multiplier.

If you prefer not to use the ICAO calculator, we recommend the emission factors in Table 7.28 and Table 7.29. These emission factors follow those published online by the UK Department of Business, Energy and Industrial Strategy conversion factors (Conversion factors 2025: condensed set (for most users)) and include a distance uplift of 8 per cent and a radiative forcing multiplier of 1.7.

Table 7.28: Emission factors for international air travel without radiative forcing multiplier
Emissions Source Unit kg CO₂–e/unit CO₂/unit (kg CO₂–e) CH₄/unit (kg CO₂–e) N₂O/unit (kg CO₂–e)
Without Radiative Forcing
Short–haul (<3700km): Average passenger pkm 0.07559 0.07466 0.00001 0.00092
Short–haul (<3700km): Economy class pkm 0.07435 0.07344 0.00001 0.0009
Short–haul (<3700km): Business class pkm 0.11152 0.11016 0.00001 0.00135
Long–haul (>3700km): Average passenger pkm 0.09043 0.08913 0.00001 0.00129
Long–haul (>3700km): Economy class pkm 0.06926 0.06826 0.00001 0.00099
Long–haul (>3700km): Premium economy class pkm 0.1108 0.10922 0.00001 0.00157
Long–haul (>3700km): Business class pkm 0.20082 0.19795 0.00002 0.00285
Long–haul (>3700km): First class pkm 0.27701 0.27304 0.00003 0.00394
Table 7.29: Emission factors for international air travel with radiative forcing multiplier
Emissions Source Unit kg CO₂–e/unit CO₂/unit (kg CO₂–e) CH₄/unit (kg CO₂–e) N₂O/unit (kg CO₂–e)
With Radiative Forcing
Short–haul (<3700km): Average passenger pkm 0.12786 0.12693 0.00001 0.00092
Short–haul (<3700km): Economy class pkm 0.12576 0.12485 0.00001 0.0009
Short–haul (<3700km): Business class pkm 0.18863 0.18727 0.00001 0.00135
Long–haul (>3700km): Average passenger pkm 0.15282 0.15152 0.00001 0.00129
Long–haul (>3700km): Economy class pkm 0.11704 0.11604 0.00001 0.00099
Long–haul (>3700km): Premium economy class pkm 0.18725 0.18567 0.00001 0.00157
Long–haul (>3700km): Business class pkm 0.33939 0.33652 0.00002 0.00285
Long–haul (>3700km): First class pkm 0.46814 0.46417 0.00003 0.00394

The emission factors from the UK DESNZ are calculated regarding the indirect and direct climate change effects. For continuity in this guidance, we have categorised the international air travel emission factors by whether a radiative forcing multiplier was applied, as outlined in this section. Further information can be found in paragraphs 8.37 to 8.41 in the 2025 UK DESNZ Methodology Paper for Conversion Factors.

7.5.2.1 GHG inventory development

To calculate emissions for international air travel, collect information on passengers flying, their departure and destination airports, flight length, travel class and, if practical, the type of aircraft. Your travel provider may be able to provide this information. Information on flight distance will be required to determine whether the short- or long-haul factors should be used.

To calculate emissions for international air travel, gather the information on how far each passenger flew for each flight. Multiply this by the factors in Table 7.28 or Table 7.29. Use the specified emission factors for different cabin classes if information is available. If unknown, use the average emission factors.

Applying the equation E = Q x F this means:

  • E = emissions from the emissions source in kg CO2-e within the reporting period
  • Q = passengers multiplied by distance flown (pkm)
  • F = appropriate emission factors from Table 7.28 or Table 7.29.
INTERNATIONAL AIR TRAVEL: EXAMPLE CALCULATION

An entity makes five flights from Auckland to Shanghai (9,346 km each way). On the first trip, two people flew return to Shanghai on the same flight in economy class. On the second trip, three people flew return to Shanghai and the cabin classes were not recorded. Long-haul (>3,700 km) emission factors with radiative forcing are used.

For the two people who travel economy class: Passenger kilometres travelled = (2 × 9,346) × 2 = 37,384 pkm

Gas Calculation Emissions (kg CO₂-e)
CO₂ emissions 37,384 x 0.11604 kg CO₂-e per pkm 4,340 kg CO₂-e
CH₄ emissions 37,384 x 0.00001 kg CO₂-e per pkm 0.374 kg CO₂-e
N₂O emissions 37,384 x 0.00099 kg CO₂-e per pkm 37.0 kg CO₂-e
Total CO₂-e emissions 37,384 x 0.11704 kg CO₂-e per pkm 4,380 kg CO₂-e

For the three people with unknown (average) travel classes: Passenger kilometres travelled = (3 × 9,346) × 2 = 56,076 pkm

Gas Calculation Emissions (kg CO₂-e)
CO₂ emissions 56,076 x 0.15152 kg CO₂-e per pkm 8,500 kg CO₂-e
CH₄ emissions 56,076 x 0.00001 kg CO₂-e per pkm 0.561 kg CO₂-e
N₂O emissions 56,076 x 0.00129 kg CO₂-e per pkm 72.3 kg CO₂-e
Total CO₂-e emissions 56,076 x 0.15282 kg CO₂-e per pkm 8,570 kg CO₂-e

Total CO2-e emissions from international air travel = 4,380 kg CO₂-e + 8,570 kg CO₂-e = 12,900 kg CO₂-e

Note: Numbers may not add due to rounding.

7.5.2.2 Emission factor derivation methodology

The 2025 UK DESNZ Methodology Paper for Conversion Factors publication discusses the methodology in more detail, including changes over time.

7.5.2.3 Assumptions, limitations and uncertainties

The emission factors in Table 7.28 and Table 7.29 are based on UK and European data. The short-haul emission factor applies to international flights of less than 3,700 km. The long-haul factor applies to flights of more than 3,700 km.

The UK DESNZ endorses a great circle distance uplift factor to account for non-direct (ie, not along the straight-line/great-circle between destinations) routes and delays/circling. The 8 percent uplift factor applied by UK DESNZ is based on the analysis of flights arriving and departing from the United Kingdom. This figure is likely to be overstated for international flights to/from New Zealand (initial estimates from Airways New Zealand suggest it is likely to be less than 5 per cent). In the absence of a New Zealand-specific figure for international flights, we recommend an 8 per cent uplift factor. This figure is comparable to an IPCC publication, Aviation and the Global Atmosphere (refer to section 8.2.2.3)7, which suggests for European flights the average flight distance is about 9 per cent to 10 per cent greater than the actual flight track distance.

The emission factors refer to aviation’s direct GHG emissions including carbon dioxide, methane and nitrous oxide. There is currently uncertainty over the other climate change impacts of aviation (including water vapour and indirect GHGs, among other factors), which the IPCC estimated to be up to two to four times those of carbon dioxide alone. However, the science is currently uncertain and New Zealand’s Greenhouse Gas Inventory 1990−2024 does not use a multiplier.

International travel is divided by class of travel. Emissions vary by class because they are based on the number of people on a flight. Business class passengers use more space and facilities than economy class travellers. If everyone flew business class, fewer people could fit on the flight and therefore emissions per person would be higher.

7.6 Helicopters

This section provides emission factors for some commonly used helicopters in New Zealand. Business activities that require the use of helicopters might include entities involved in tourism, air transport, agricultural operations, or emergency services.

Table 7.30: Emission factors for helicopters
Emissions Source Unit kg CO₂–e/unit CO₂/unit (kg CO₂–e) CH₄/unit (kg CO₂–e) N₂O/unit (kg CO₂–e)
Helicopter
Eurocopter AS 350B Squirrel hours 465.05 461.54 0.0903539 3.42054
Eurocopter AS 350B3 Squirrel hours 481.147 477.515 0.0934813 3.53893
Bell 206B hours 320.606 318.185 0.06229 2.35812
Robinson R44 hours 188.153 186.688 0.0376825 1.42655
Robinson R22 Beta hours 226.16 224.4 0.0452945 1.71472

7.6.1 GHG inventory development

These emission factors can be used where the amount of fuel used is not known. Obtaining fuel data will provide a more accurate estimate of your carbon emissions. To calculate emissions from operating helicopters when only the number of operating hours is known.

Applying the equation E = Q x F this means:

  • E = emissions from the emissions source in kg CO2-e within the reporting period
  • Q = hours of operating time (hours)
  • F = emission factors for correlating helicopter type, from Table 7.30.

7.6.1.1 HELICOPTER USE: EXAMPLE CALCULATION

An agricultural operation used a Eurocopter AS 350B Squirrel to apply topdressing and other spraying activities. They could not obtain data on the amount of fuel used, but had recorded 10 flying hours over a given year.

Gas Calculation Emissions (kg CO₂-e)
CO₂ emissions 10 x 461.54 kg CO₂-e per hours 4,620 kg CO₂-e
CH₄ emissions 10 x 0.0903539 kg CO₂-e per hours 0.904 kg CO₂-e
N₂O emissions 10 x 3.42054 kg CO₂-e per hours 34.2 kg CO₂-e
Total CO₂-e emissions 10 x 465.05 kg CO₂-e per hours 4,650 kg CO₂-e

Note: Numbers may not add due to rounding.

7.6.2 Emission factor derivation methodology

These emission factors were derived from the Swiss Federal Office of Civil Aviation’s (FOCA) Guidance on the Determination of Helicopter Emissions. This contains air emissions data (non-GHG) for one hour of flying time, including fuel consumption, for a range of helicopter models.This contains air emissions data (non-GHG) for one hour of flying time, including fuel consumption, for a range of helicopter models.

The one-hour emissions values are used, which assume a combination of rotations and cruise per flight-hour.

The fuel consumption (provided in kgs) was converted to litres using assumed densities of 0.794 kg per litre and 0.716 kg per litre, for Jet A1 and aviation gas respectively. Turbine engine helicopters are assumed to use Jet A1 while piston helicopters are assumed to use aviation gas. We then applied the Jet A1 and aviation gas emission factors from Transport fuels section above to determine the emission factor for one hour of operation.

We used the aircraft register on the New Zealand Civil Aviation Authority (CAA) website8 to identify the most commonly registered helicopter models in the country.

7.6.3 Assumptions, limitations and uncertainties

Obtaining the amount of fuel used for helicopter activities would provide a more accurate estimate of carbon emissions, than using this emission factor which is based on operating hours.

A number of factors will influence the accuracy of this emission factor for a given operating hour, such as the cruising speed, the take-off and approach, and the way the helicopter is being used.

Finally, if your entity has a helicopter model that is not provided here, you may wish to choose the model that seems to be the best fit. However, this approach will have limitations, due to variations that include engine operating power, and the size and number of engines.

7.7 Accommodation

Accommodation is an indirect (Scope 3) emissions source associated with business travel. The emission factors for hotel stays have been updated using factors from the 2025 edition of the Cornell Hotel Sustainability Benchmarking Index (CHSB) Index,9 which provides data for the 2023 calendar year.

We obtained the 62 emission factors from the M1 tab of the source spreadsheet, using the median values for all hotels. The factors are in CO2-e and are not available by gas type. For more information on the Cornell methodology, see the Hotel Sustainability Benchmarking Index 2025 guidance document.10

Note these emission factors are based on either AR4 or AR5 GWP values, depending on the country. The reason is some countries submit their emission factors to this study in terms of CO2-e, while other countries break it down into the three main GHG types. In the latter cases, the AR5 GWPs were applied.

The provision of these emission factors can be limited by the availability of data in different countries. If the factor for a certain country is not available in Table 7.31, we recommend using factors from a previous edition of this guidance.

We continue to report on the emissions estimates from the “Non-Resort” category.

Table 7.31: Accommodation emission factors by unit (room per night)
Emissions Source Unit kg CO₂–e/unit CO₂/unit (kg CO₂–e) CH₄/unit (kg CO₂–e) N₂O/unit (kg CO₂–e)
Hotel Stays
Argentina Room per night 30.5 30.5 0 0
Australia Room per night 29.9039 29.9039 0 0
Austria Room per night 8.66548 8.66548 0 0
Belgium Room per night 10.306 10.306 0 0
Brazil Room per night 11.6152 11.6152 0 0
Canada Room per night 9.99379 9.99379 0 0
Chile Room per night 23.4645 23.4645 0 0
China Room per night 41.9961 41.9961 0 0
Colombia Room per night 11.3694 11.3694 0 0
Costa Rica Room per night 4.63807 4.63807 0 0
Czech Republic Room per night 22.0474 22.0474 0 0
Dominican Republic Room per night 38.6601 38.6601 0 0
Ecuador Room per night 16.2383 16.2383 0 0
Egypt Room per night 43.4324 43.4324 0 0
Finland Room per night 11.085 11.085 0 0
France Room per night 6.99968 6.99968 0 0
Georgia Room per night 23.6745 23.6745 0 0
Germany Room per night 13.5052 13.5052 0 0
Greece Room per night 16.3115 16.3115 0 0
Hong Kong Room per night 53.0916 53.0916 0 0
Hungary Room per night 19.2408 19.2408 0 0
India Room per night 51.0974 51.0974 0 0
Indonesia Room per night 44.684 44.684 0 0
Ireland Room per night 13.8604 13.8604 0 0
Israel Room per night 36.0594 36.0594 0 0
Italy Room per night 16.6438 16.6438 0 0
Japan Room per night 30.1141 30.1141 0 0
Jordan Room per night 43.885 43.885 0 0
Kazakhstan Room per night 42.0011 42.0011 0 0
South Korea Room per night 31.5832 31.5832 0 0
Malaysia Room per night 53.1705 53.1705 0 0
Mexico Room per night 18.3703 18.3703 0 0
Morocco Room per night 47.8092 47.8092 0 0
Netherlands Room per night 12.615 12.615 0 0
New Zealand Room per night 8.33691 8.33691 0 0
Nigeria Room per night 42.9759 42.9759 0 0
Oman Room per night 46.4389 46.4389 0 0
Panama Room per night 21.0694 21.0694 0 0
Peru Room per night 17.3733 17.3733 0 0
Philippines Room per night 50.552 50.552 0 0
Poland Room per night 25.0656 25.0656 0 0
Portugal Room per night 12.26 12.26 0 0
Puerto Rico– USA Room per night 33.157 33.157 0 0
Qatar Room per night 70.7759 70.7759 0 0
Romania Room per night 16.6843 16.6843 0 0
Russian Federation Room per night 21.5086 21.5086 0 0
Saudi Arabia Room per night 60.6826 60.6826 0 0
Singapore Room per night 27.2271 27.2271 0 0
Slovak Republic Room per night 10.2154 10.2154 0 0
South Africa Room per night 29.396 29.396 0 0
Spain Room per night 10.9898 10.9898 0 0
Switzerland Room per night 5.9885 5.9885 0 0
Taiwan– China Room per night 37.0227 37.0227 0 0
Tanzania Room per night 21.4907 21.4907 0 0
Thailand Room per night 31.2815 31.2815 0 0
Turkey Room per night 29.1942 29.1942 0 0
United Arab Emirates Room per night 42.731 42.731 0 0
United Kingdom Room per night 10.0313 10.0313 0 0
United States Room per night 15.0548 15.0548 0 0
Vietnam Room per night 52.7891 52.7891 0 0
Zambia Room per night 9.84687 9.84687 0 0
Caribbean Region Room per night 33.2014 33.2014 0 0

7.7.1 GHG inventory development

To calculate emissions from accommodation during business trips, collect data on the number of nights and the country stayed in.

Applying the equation E = Q x F this means:

  • E = emissions from the emissions source in kg CO2-e within the reporting period
  • Q = rooms per night
  • F = emission factors for the country stayed in from Table 7.31.

7.7.1.1 ACCOMODATION: EXAMPLE CALCULATION

An entity sends six people to a conference in Australia. They book three rooms for four nights. 3 rooms x 4 nights = 12

Gas Calculation Emissions (kg CO₂-e)
CO₂ emissions 12 x 29.9039 kg CO₂-e per Room per night 359 kg CO₂-e
CH₄ emissions 12 x 0 kg CO₂-e per Room per night 0 kg CO₂-e
N₂O emissions 12 x 0 kg CO₂-e per Room per night 0 kg CO₂-e
Total CO₂-e emissions 12 x 29.9039 kg CO₂-e per Room per night 359 kg CO₂-e

Note: Numbers may not add due to rounding.

7.7.2 Assumptions, limitations and uncertainties

The Hotel Sustainability Benchmarking Index 2025 guidance document outlines the limitations of the study. These include:

  • It is skewed towards upmarket and chain hotels, meaning the data may not be representative of the entire hotel industry, particularly the economy and midscale segments.

  • The results do not distinguish a property’s facilities, except for outsourced laundry services, which are taken into consideration. This means it is difficult to compare two hotels because some may contain distinct attributes (such as restaurants, fitness centres and swimming pools) while others do not.

  • The data have not been independently verified by a third-party provider.

  1. New Zealand Transport Agency: https://nzta.govt.nz/resources/new-zealand-motor-vehicle-register-statistics/new-zealand-vehicle-fleet-open-data-sets.↩︎

  2. Te Manatū Waka Ministry of Transport: https://www.transport.govt.nz/statistics-and-insights/fleet-statistics/sheet/annual-fleet-statistics.↩︎

  3. Te Manatū Waka Ministry of Transport: https://www.transport.govt.nz/statistics-and-insights/fleet-statistics/sheet/annual-fleet-statistics.↩︎

  4. GHG Protocol Technical Guidance for Calculating Scope 3 Emissions: https://ghgprotocol.org/sites/default/files/standards_supporting/Chapter6.pdf.↩︎

  5. Te Manatū Waka Ministry of Transport: https://www.transport.govt.nz/statistics-and-insights/fleet-statistics/sheet/annual-fleet-statistics.↩︎

  6. Kerosene (ils.co.nz).↩︎

  7. https://archive.ipcc.ch/ipccreports/sres/aviation/121.htm#8223↩︎

  8. https://www.aviation.govt.nz/aircraft/aircraft-registration/aircraft-register-search/.↩︎

  9. Hotel Sustainability Benchmarking Index 2025: Carbon, Energy, Water, and Waste.↩︎

  10. https://greenview.sg/wp-content/uploads/2025/09/CHSB2025-Guidance-on-Emission-Factors-091525.pdf.↩︎