---
title: 8. Freight transport emission factors
# format: html
# number-sections: true
number-offset: 8
order: 8
---

We provide emission factors for freighting goods (in tonne kilometres, tkm) and for the actual freight vehicles (in km). We provide freight vehicle emission factors (in km) for road light commercial and heavy goods vehicles (HGVs). Users should note that these are average emission factors for certain vehicle categories of the New Zealand vehicle fleet. The actual emissions for a specific vehicle in a specific trip could be different.

## Overview of changes since previous update

Rail freight emission factors have been updated using 2023 source data from KiwiRail.

## Road freight

Entities freighting goods through third-party providers can categorise road freight emissions as indirect (Scope 3). We generated emission factors for freight vehicles (in km travelled) and an average emission factor for freighting goods by road in tkm. Where the entity’s goods are only part of the load, the tkm emission factor should be used as the way of allocating emissions between the different goods on the same truck. Downstream and upstream transportation and distribution can also be considered.Refer to the [GHG Protocol](https://ghgprotocol.org/corporate-standard).

The three road freight emission factors provided in tkm are for urban delivery heavy trucks, long-haul heavy trucks and all trucks. Urban delivery heavy trucks include vans and road user charge (RUC) type 2 trucks, such as those powered vehicles with two axles. Please note these trucks could carry trailers and most of their travel would be for urban delivery. Long-haul heavy trucks include other RUC types, such as those powered vehicles with three or more axles. Most of them would be used for relatively long-distance travel. The emission factor for ‘all trucks’ should be used for a large fleet with a good mix of small and large trucks. Users should be aware that the emission behaviour of individual vehicles could vary greatly.

Te Manatū Waka Ministry of Transport’s Vehicle Fleet Emissions Model provided the real-world fuel consumption rates of the vehicle fleet. We decided to split the fleet into three categories and develop average emission factors for these.

• Pre-2010 fleet is based on the average fuel consumption data from 1970 to 2010. We assume there are no electric vehicles or diesel hybrids.

• 2010–2015 fleet is based on the average fuel consumption data from vehicles produced between 2010 and 2015.

• Post-2015 fleet is based on the average fuel consumption data from vehicles produced from 2015 onwards.

TONNE KILOMETRES (TKM) <!-- TODO: This could be a table -->

### Light commercial vehicle emission factors

**Table 46: Emission factors for light commercial vehicles manufactured pre-2010**

**Table 47: Emission factors for light commercial vehicles manufactured between 2010 and 2015**

**Table 48: Emission factors for light commercial vehicles manufactured between 2015 and 2020**

**Table 49: Emission factors for light commercial vehicles manufactured after 2020**

**Table 50: Default light commercial vehicle values (based on pre-2010 fleet and a 2000–3000 cc engine size)**

### Heavy goods vehicles emission factors

`Table 51` contains the default emission factors for heavy goods vehicles, based on a pre-2010 fleet.

**Table 51: Emission factors for heavy goods vehicles manufactured pre-2010**.

`Table 52` contains the default emission factors for heavy goods vehicles, based on a 2010–2015 fleet

**Table 52: Emission factors for heavy goods vehicles manufactured between 2010 and 2015**

Table 53 contains the default emission factors for heavy goods vehicles, based on a post-2015 fleet

**Table 53: Emission factors for heavy goods vehicles manufactured post-2015**

`Table 54` contains the default emission factors for heavy goods vehicles, based on a pre-2010 fleet and a gross vehicle mass of \<7500 kg.

`Table 55` contains emission factors for freighting goods

The tkm emission factor should be used where there is a mixed consignment on the same truck.

**Table 55: Emission factors for freighting goods by road**

### GHG inventory development

If an entity uses freight vehicles, they can calculate the emissions from the kilometres travelled. Multiply the distances by the emission factors in table 46 to table 54.

Applying the equation E = Q x F [(section 2)](2_how-to.qmd##Calculating_an_emissions_factor), this means:

E = emissions from the emissions source in kg CO2-e per year

Q = km travelled by specific freight vehicle one way

F = appropriate emission factors from `table 46` to `table 54`.

For emissions from freighting goods, users need to know the weight in tonnes of the goods freighted as well as the kilometres travelled. These two numbers multiplied together is the tkm. Multiply the tkm by the emission factors in table 55. Applying the equation E = Q x F [(section 2)](2_how-to.qmd##Calculating_an_emissions_factor), this means:

E = emissions from the emissions source in kg CO2-e per year

Q = tonne × kilometres travelled one way

F = appropriate emission factors from table 55.

ROAD FREIGHT: EXAMPLE CALCULATION

For vehicles that run on electricity, care should be taken not to double-count emissions from electricity use that is already captured from reporting of an entities on-site

electricity consumption.

### Emission factor derivation methodology

The 2022 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. The litres of fuel (or kWh of electricity) consumed per 100 km are provided in Table 56 and Table 57. Note the figures in table 57 are unchanged from the

previous edition as updated figures were not available.

**Table 56: Light commercial vehicles (energy consumption per 100 km)**

**Table 57: Heavy goods vehicles (energy consumption per 100 km)**

The equation used to calculate the emission factor for each GHG is:

[𝑟𝑒𝑎𝑙˗𝑤𝑜𝑟𝑙𝑑 𝑓𝑢𝑒𝑙 𝑐𝑜𝑛𝑠𝑢𝑚𝑝𝑡𝑖𝑜𝑛 × 𝑒𝑚𝑖𝑠𝑠𝑖𝑜𝑛 𝑐𝑜𝑛𝑣𝑒𝑟𝑠𝑖𝑜𝑛 𝑓𝑎𝑐𝑡𝑜𝑟]{.underline}

100 km

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.

We multiplied the values for fuel consumption by the emission conversion factors provided in `table 4`.

The default emission factors for freighting vehicles include the following assumptions based on Te Manatū Waka Ministry of Transport’s *The New Zealand 2022 Vehicle Fleet: Data Spreadsheet*.

• Light commercial vehicles are on average 12.5 years old, 39 which corresponds to a 2010 year of manufacture.

• The most common engine size is 2000−3000 cc, therefore, we used a pre-2010 fleet and a 2000-3000 cc engine size for the default values.

• Heavy trucks are on average 18 years old and the most common gross vehicle mass is \<7500 kg, therefore we selected a pre-2010 vehicle fleet with a gross vehicle mass of \<7500 kg.

• Using the Motor Vehicle Register,40 79 per cent of goods vans/trucks and utility vehicles are diesel. Therefore diesel vehicles are assumed for the all-trucks factor.

Emission factors for freighting goods (tkm) are from the Te Manatū Waka Ministry of Transport’s presentation ‘Real-world fuel economy of heavy trucks’.[^1]

[^1]: Te Manatū Waka Ministry of Transport: www.knowledgehub.transport.govt.nz/assets/TKH-Uploads/TKC-2019/Real-world-fuel-economy-of-heavy-trucks.pdf

This source provides emission factors in terms of g CO2-e/tkm, not for each of the three GHGs (see table 58). Therefore, we calculated emission factors for carbon dioxide, methane and nitrous oxide based on the GHG split ratio of the fuel used, which was diesel (see table 59). This ratio is applied to produce the emission factors provided in `table 55`.

**Table 58: Data used to calculate the road freight (tkm) emission factor**

**Table 59: Calculating the ratio of gases in diesel**

We multiplied the 0.135 kg CO~2~-e [(Road Freight: Example Calculation box)](https://environment.govt.nz/assets/publications/Measuring-Emissions-2024/Measuring-emissions_Detailed-guide_2024_ME1829.pdf#page=90&zoom=100,117,577) result by the calculated factor to provide emission factors broken down by gas type.

### 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 major source of uncertainty for the freighting goods emission factor is that net tonne-kilometres must be inferred from truck (RUC) returns and the Waka Kotahi NZ Transport Agency (NZTA) truck weigh-in-motion statistics.

The sources used to develop these emission factors will have inbuilt assumptions, limitations and uncertainties. To investigate these, see the documents referenced.

## Rail freight

In New Zealand, KiwiRail owns the rail infrastructure and has provided the information to calculate the emission factor. The emission factor for freighting goods by rail is in `table 60`.

Table 60: Emission factors for rail freight

### GHG inventory development

Users should collect data on the weight of goods freighted (tonnes), and the distance travelled (kilometres). For each journey, multiply the total tonnes by the total km travelled.

Applying the equation E = Q x F [(section 2)](2_how-to.qmd##Calculating_an_emissions_factor), this means:

E = emissions from the emissions source in kg CO2-e per year

Q = tonnes of freight × km travelled

F = emission factors in `table 60`.

<!-- TODO:RAIL FREIGHT: EXAMPLE CALCULATION -->

### Emission factor derivation methodology

KiwiRail provided the following information used to calculate the emission factors.

Table 61: Information provided by KiwiRail

Note: NTK (net tonne km) is the sum of the tonnes carried multiplied by the distance travelled.

To calculate emissions from freight-only fuel, multiply the litres by the diesel emission factor in `table 4`:

𝑒𝑚𝑖𝑠𝑠𝑖𝑜𝑛𝑠 𝑓𝑟𝑜𝑚 𝑓𝑢𝑒𝑙 = 𝑓𝑟𝑒𝑖𝑔ℎ𝑡˗𝑜𝑛𝑙𝑦 𝑓𝑢𝑒𝑙 × 𝑑𝑖𝑒𝑠𝑒𝑙 𝑒𝑚𝑖𝑠𝑠𝑖𝑜𝑛 𝑓𝑎𝑐𝑡𝑜𝑟

To calculate emissions from electricity, multiply the net kWh by the emission factors in `table 9` or `table 10`:

𝑒𝑚𝑖𝑠𝑠𝑖𝑜𝑛𝑠 𝑓𝑟𝑜𝑚 𝑒𝑙𝑒𝑐𝑡𝑟𝑖𝑐𝑖𝑡𝑦 = 𝑒𝑙𝑒𝑐𝑡𝑟𝑖𝑐𝑖𝑡𝑦 𝑁𝐼𝑀𝑇 × 𝑝𝑢𝑟𝑐ℎ𝑎𝑠𝑒𝑑 𝑒𝑙𝑒𝑐𝑡𝑟𝑖𝑐𝑖𝑡𝑦 𝑒𝑚𝑖𝑠𝑠𝑖𝑜𝑛 𝑓𝑎𝑐𝑡𝑜𝑟𝑠

To calculate emissions from transmission and distribution losses from the purchased electricity, multiply the kWh by the emission factors in `table 12`:

𝑒𝑚𝑖𝑠𝑠𝑖𝑜𝑛𝑠 𝑓𝑟𝑜𝑚 𝑇&𝐷 𝑙𝑜𝑠𝑠𝑒𝑠 = 𝑒𝑙𝑒𝑐𝑡𝑟𝑖𝑐𝑖𝑡𝑦 𝑁𝐼𝑀𝑇 × 𝑇&𝐷 𝑙𝑜𝑠𝑠𝑒𝑠 𝑓𝑜𝑟 𝑝𝑢𝑟𝑐ℎ𝑎𝑠𝑒𝑑 𝑒𝑙𝑒𝑐𝑡𝑟𝑖𝑐𝑖𝑡𝑦 𝑒𝑚𝑖𝑠𝑠𝑖𝑜𝑛 𝑓𝑎𝑐𝑡𝑜𝑟

Divide these total emissions by the freight volumes in tonnes to give emissions per tkm:

𝑒𝑚𝑖𝑠𝑠𝑖𝑜𝑛 𝑝𝑒𝑟 𝑡𝑘𝑚 = [𝑒𝑚𝑖𝑠𝑠𝑖𝑜𝑛𝑠 𝑓𝑟𝑜𝑚 𝑓𝑢𝑒𝑙 + 𝑒𝑚𝑖𝑠𝑠𝑖𝑜𝑛𝑠 𝑓𝑟𝑜𝑚 𝑒𝑙𝑒𝑐𝑡𝑟𝑖𝑐𝑖𝑡𝑦 + 𝑒𝑚𝑖𝑠𝑠𝑖𝑜𝑛𝑠 𝑓𝑟𝑜𝑚 𝑇&𝐷 𝑙𝑜𝑠𝑠𝑒𝑠]{.underline}

```         
         𝑓𝑟𝑒𝑖𝑔ℎ𝑡 𝑣𝑜𝑙𝑢𝑚𝑒𝑠 (𝑛𝑒𝑡) × 1000
```

### Assumptions, limitations and uncertainties

The figure for net tkm includes the weight for third-party tare weight containers. KiwiRail does not own or control those containers and it is the responsibility of the customer to load and unload them. The alternative for these customers would be to transport freight by road. Therefore, these figures reflect the actual freight (including the weight of empty and loaded containers) that KiwiRail moved.

## Air freight

In the absence of New Zealand data, we have adopted the air freight emission factors from the latest [UK Greenhouse gas reporting: Conversion factors 2023](https://www.gov.uk/government/publications/greenhouse-gas-reporting-conversion-factors-2023). These emission factors are Scope 3. Refer to section 7.5 for further guidance on radiative forcing to inform your choice of emission factor. While the radiative forcing multiplier of 1.7 used in this guidance is based on current scientific evidence and research, this figure is subject to significant uncertainty.

Emissions from aviation have both direct (CO~2~, CH~4~ and N~2~O) and indirect (non-CO2 emissions eg, water vapour, contrails, NO~x~) climate change effects. Two sets of emission factors for air freight are presented here; one that includes the indirect effects of non-CO2 emissions and one that represents direct effects only.

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.

Entities should include the indirect effects of non-CO2 emissions when reporting air freight emissions to capture the full climate impact of their travel. However, it should be noted that there is significant scientific uncertainty around the magnitude of the indirect effect of non-CO2 aviation emissions and it is an active area of research. Further information can be found in paragraphs 8.40 to 8.45 in the [2023 UK DESNZ Methodology Paper for Conversion Factors](https://assets.publishing.service.gov.uk/media/647f50dd103ca60013039a8a/2023-ghg-cf-methodology-paper.pdf).

**Table 62: Air freight emission factors without radiative forcing multiplier**

**Table 63: Air freight emissions with radiative forcing multiplier**

### GHG inventory development

Users should collect data on the weight in tonnes of goods freighted by air and the distance travelled. For each journey, multiply the total tonnes by the total km travelled.

Applying the equation E = Q x F (\[section 2\])(2_how-to.qmd##Calculating_an_emissions_factor), this means:

E = emissions from the emissions source in kg CO2-e per year

Q = tonnes of freight × km travelled

F = appropriate emission factors in `Table 62` or `Table 63`.

AIR FREIGHT: EXAMPLE CALCULATION <!-- TODO: This could be a table -->

### Emission factor derivation methodology

The [2023 UK DESNZ Methodology Paper for Conversion Factors](https://assets.publishing.service.gov.uk/media/647f50dd103ca60013039a8a/2023-ghg-cf-methodology-paper.pdf) contains full details on the derivation of these emission factors.

### Assumptions, limitations and uncertainties

As we adopted these emission factors from the UK DESNZ emissions for air freight to and from the UK, we assume the same factors apply to New Zealand. We have not considered the difference in the size of aircraft transporting domestic air freight – this limits the accuracy of these emission factors to better reflect New Zealand domestic air freight. The [2023 UK DESNZ Methodology Paper for Conversion Factors goes](https://assets.publishing.service.gov.uk/media/647f50dd103ca60013039a8a/2023-ghg-cf-methodology-paper.pdf) into more detail behind the GHG conversion factors.

We included the emission factors with radiative forcing to account for additional radiative forcing from emissions arising from aircraft transport at altitude (jet aircraft).

## Coastal and international shipping freight

We calculated the domestic coastal shipping emission factor, Table 64 based on the findings from the Te Manatū Waka Ministry of Transport presentation ‘Real-world fuel economy of heavy trucks’,[^2] prepared for the 2019 Transport Knowledge Conference. We adopted the international shipping emission factors from the [UK Greenhouse gas reporting: Conversion factors 2023](https://www.gov.uk/government/publications/greenhouse-gas-reporting-conversion-factors-2023).

[^2]: Te Manatū Waka Ministry of Transport: www.knowledgehub.transport.govt.nz/assets/TKH-Uploads/TKC-2019/Real-world-fuel-economy-of-heavy-trucks.pdf.

**Table 64: Coastal shipping emission factors**

Note: These numbers are rounded to three decimal places unless the number is significantly small.

**Table 65: International shipping emission factors**

Note: CEU = car equivalent unit; dwt = deadweight tonnes; LM = lanemetre; TEU = twenty-foot equivalent unit.

### GHG inventory development

Users should collect data on the weight in tonnes of goods freighted, and the distance travelled. For each journey, multiply the total tonnes by the total km travelled.

Applying the equation E = Q x F [section 2](2_how-to.qmd##Calculating_an_emissions_factor), this means:

E = emissions from the emissions source in kg CO2-e per year

Q = tonnes of freight × km travelled

F = appropriate emission factors from `Table 64` or `Table 65`

MULTIPLE FREIGHT MODES: EXAMPLE CALCULATION <!-- TODO:This could be a table -->

### Emission factor derivation methodology

We based the emission factors for coastal shipping on figures included in the Te Manatū Waka Ministry of Transport presentation ‘Real world fuel economy of heavy trucks’,[^3] prepared for the 2019 Transport Knowledge Conference.

[^3]: Te Manatū Waka Ministry of Transport: www.knowledgehub.transport.govt.nz/assets/TKH-Uploads/TKC-2019/Real-world-fuel-economy-of-heavy-trucks.pdf.

This source provides emission factors in terms of g CO~2~-e/tkm, not for each of the three GHGs (see Table 66). Therefore, we calculated emission factors for carbon dioxide, methane and nitrous oxide based on the GHG split ratio of the fuel used, which was heavy fuel oil. This ratio is applied to produce the emission factors provided in `Table 64`.

**Table 66: Coastal shipping data**

For international shipping, we used the Freight Information Gathering System (FIGS)[^4] to identify which types of ships visit New Zealand, and their average sizes. We then adopted the [UK Greenhouse gas reporting: Conversion factors 2023](https://www.gov.uk/government/publications/greenhouse-gas-reporting-conversion-factors-2023) for the relevant ships and adapted the average emission factors to reflect ship sizes visiting New Zealand.

[^4]: Freight Information Gathering System: www.transport.govt.nz/statistics-and-insights/freight-and-logistics/

We identified the following shipping types as visiting New Zealand:

• container ships

• reefer (refrigerated cargo ship)

• bulk carrier

• RoRo (roll-on, roll-off)

• oil/gas tanker

• vehicle carrier

• general cargo.

We used MoT’s FIGS[^5] to find out the average sizes of ships visiting New Zealand. Ships are measured in deadweight tonnes (dwt), twenty-foot equivalent unit (TEU), car equivalent unit (CEU) or lanemetre (LM).

[^5]: Freight Information Gathering System, overseas ships: www.transport.govt.nz/statistics-and-insights/freight-and-logistics/.

• Bulk carrier is 36,900 dwt and therefore in the 35,000–59,999 dwt category.

• General cargo is 15,800 dwt and therefore in the 10,000+ dwt category.

• Container ship is 3,194 TEU and therefore in the 3,000–4,999 TEU category.

• Vehicle carrier (transport) is unknown and therefore the same as the UK average.

• RoRo ferry is unknown and therefore the same as the UK average.

• As there is only one emission factor for all refrigerated cargo an average was not necessary.

Emission factors for these have been adopted from the [UK Greenhouse gas reporting: Conversion factors 2023](https://www.gov.uk/government/publications/greenhouse-gas-reporting-conversion-factors-2023). Refer to that document for details on the methodology.

### Assumptions, limitations and uncertainties

We assumed the New Zealand coastal shipping fleet is similar to that in the [STREAM Freight Handbook](https://cedelft.eu/publications/stream-freight-transport-2020/). These figures have a high degree of uncertainty as they are based on international data for coastal shipping.

We carried over the assumptions for the international shipping emission factors from the [2023 UK DESNZ Methodology Paper for Conversion Factors](https://assets.publishing.service.gov.uk/media/647f50dd103ca60013039a8a/2023-ghg-cf-methodology-paper.pdf).