Greenhouse gas inventory definitions and source information

An A-Z summary of categories included in our current emissions measurement.

Accommodation - Work related

Parameter  Details 
 Unit  Visitor night (v.ngt)
Definition Work-related hotel stays booked and paid for by the University
Measurement The number of hotel room nights booked and paid for in the specified country, within the calendar year, for the University and UniServices
Data source Hotel reports provided by supplier through Strategic Procurement Manager
ISO standard Category 3: Indirect emissions from transportation / Business travel - Accommodation
GHG Protocol Scope 3 - Additional

Air travel - Work related

Parameter  Details 
 Unit Person kilometres (pkm)
Definition Air travel for work-related activities by staff, including students employed at the University
Measurement

Person kilometres travelled for flights boarded within the calendar year, for the university and UniServices

Domestic flight emissions are calculated based on aircraft type or similar 

Data improvements

Prior to June 2021, all flight data (2019-2021) were based on flights booked. Post June 2021, reports were based on flights boarded

Since 2022, multi-segment trips (e.g., AKL-SFO-LHR-SFO-AKL), are separated into domestic, short-haul, and long-haul travel types and pkm is calculated for each segment

Assumptions If the aircraft type is unknown, the national domestic average emission factor is used
Data source Air Travel reports provided by supplier through Strategic Procurement Manager
ISO standard Category 3: Indirect emissions from transportation / Business travel - Transport (non-company owned vehicles)
GHG Protocol Scope 3

Air travel - International students

Parameter  Details 
 Unit Person kilometres (pkm)
Definition Subset of students with international residency in the calendar year, cross-referenced with moderate confidence campus location data
Measurement Assumed person kilometres for international students that travel to New Zealand within the calendar year 
Assumptions

80% of international students known to be in New Zealand within the calendar year are assumed to take a return trip to their countries of citizenship within the same year

An overall adjustment is applied of 20% reduction to account for students that remained in New Zealand

Airport of origin is assumed based on the student country of citizenship

Data source Planning and Information Office and International Office
ISO standard Category 3: Indirect emissions from transportation /
Client and visitor transport
GHG Protocol Scope 3 Additional

CH4

Parameter  Details 
 Unit Kilogram (kg)
Definition  Chemical formula for methane (a greenhouse gas), used as a refrigerant
Measurement Kilograms of methane gas losses within the calendar year
Assumptions

Where top-up amounts are not provided by a supplier, purchases of gas and refrigerants are reported as losses

It is assumed that purchases are made for top-ups or replacement of gas stocks

Data source Refrigerant/Gas report provided by suppliers through Campus Services Manager or Strategic Procurement Manager
ISO standard Category 1: Direct emissions and removals / Leakage of refrigerants
GHG Protocol Scope 1

CO2

Parameter  Details 
 Unit Kilogram (kg)
Definition Chemical formula for carbon dioxide (greenhouse gas), used as a refrigerant
Measurement Kilograms of carbon dioxide gas losses within the calendar year
Assumptions

Where top-up amounts are not provided by a supplier, purchases of gas and refrigerants are reported as losses

It is assumed that purchases are made for top-ups or replacement of gas stocks

Data source Refrigerant/Gas report provided by suppliers through Campus Services Manager or Strategic Procurement Manager
ISO standard Category 1: Direct emissions and removals / Leakage of refrigerants
GHG Protocol Scope 1

Composting

Parameter  Details 
 Unit Kilogram (kg)
Definition Composting refers to the process where organic materials (food scraps and green waste) are converted into nutrient-rich soil through biological treatment of waste
Measurement Kilograms of food and green waste composted within the calendar year
Data source Waste reports are provided by suppliers through Waste Minimisation Specialist
ISO standard Category 4: Indirect emissions from products used by organisation / Disposal of solid waste - Not landfilled
GHG Protocol Scope 3 Additional

Decontamination of medical waste - Autoclaving

Parameter  Details 
 Unit Kilogram (kg)
Definition Autoclaving uses high temperature, high pressure steam to decontaminate certain types of medical waste before it is sent to landfill (also included in the landfill inventory)
Measurement Weight of medical waste decontaminated before being sent to landfill within the calendar year
Data source Waste reports are provided by suppliers through Waste Minimisation Specialist
ISO standard Category 4: Indirect emissions from products used by organisation / Disposal of solid waste - Not landfilled
GHG Protocol Scope 3 Additional

Diesel stationary combustion

Parameter  Details 
 Unit Litre (L)
Definition Diesel stationary combustion refers to diesel fuel used in an unmoving engine, such as a generator or power plant
Measurement Litres of stationary diesel used within the calendar year for backup power generators and fire pumps that serve University buildings
Data source Stationary fuel report provided by suppliers through Campus Services Manager
ISO standard Category 1: Direct emissions and removals / Stationary combustion
GHG Protocol Scope 1

Diesel mobile combustion

Parameter  Details 
 Unit Litre (L)
Definition Diesel mobile combustion refers to transport fuels used in an engine to move a vehicle, including cars, vans, tractors and farm vehicles
Measurement Litres of mobile combustion diesel used within the calendar year for work-related vehicles owned by the University
Data source Fuel card reports provided by suppliers through Strategic Procurement Manager
ISO standard Category 1: Direct emissions and removals / Mobile combustion (incl. company owned or leased vehicles)
GHG Protocol Scope 1

Electricity

Parameter  Details 
 Unit Kilowatt hours (kWh)
Definition Electricity purchased from the national grid (excludes carbon zero certified energy)
Measurement Kilowatt hours of energy produced from electricity purchased within the calendar year for buildings within the operational boundaries of the University
Data source Invoices provided by the suppliers through the Energy Manager
ISO standard Category 2: Indirect emissions from imported energy / Imported electricity
GHG Protocol Scope 2

Electricity distributed T&D losses

Parameter  Details 
 Unit Kilowatt hours (kWh)
Definition Losses in the transmission of electricity between the sources of supply and points of distribution
Measurement Kilowatt hours of electricity lost through transmission and distribution for electricity purchased from the national grid within the calendar year for buildings within the operational boundaries of the University
Data source Invoices provided by the suppliers through the Energy Manager
ISO standard Category 4: Indirect emissions from products used by organisation / Transmission of energy (T&D losses)
GHG Protocol Scope 3

Electricity Toitū Carbon Zero certified factor – supplier specific

Parameter Details 
 UnitKilowatt hours (kWh)
DefinitionToitū Carbon Zero certified electricity purchased from renewable sources (including wind, solar and hydro generation sources)
MeasurementKilowatt hours of energy, purchased from Toitū certified Carbon Zero electricity provider, within the calendar year, for buildings within the operational boundaries of the University
Data sourceInvoices provided by the suppliers through the Energy Manager
ISO standardCategory 2: Indirect emissions from imported energy / Imported electricity
GHG ProtocolScope 2

Electricity Toitū Carbon Zero certified factor T&D losses - supplier specific

Parameter  Details 
 Unit Kilowatt hours (kWh)
Definition Losses in the transmission of renewable electricity (including wind, solar and hydro generation sources) between the sources of supply and points of distribution
Measurement Kilowatt hours of electricity lost in transmission and distribution for electricity purchased from Toitū certified Carbon Zero electricity provider, within the calendar year for buildings within the operational
boundaries of the University
Data source Invoices provided by the suppliers through the Energy Manager
ISO standard Category 4: Indirect emissions from products used by organisation / Transmission of energy (T&D losses)
GHG Protocol Scope 3

Enteric fermentation

Parameter  Details 
 Unit Head
Definition Livestock head is defined as one animal for the 12-month measurement period. Livestock types are counted separately (cattle or sheep), and sheep includes lambs, ewes and rams
Measurement Number of livestock grazing on land owned or leased by the University
Data source Data provided by Livestock and Facility Manager
ISO standard Category 1: Direct emissions and removals / Enteric fermentation
GHG Protocol Scope 1

Freight

Parameter  Details 
 Unit Tonne-kilometre (tkm)
Definition Freight refers to goods transported by car, van, truck, rail, ship or aircraft
Measurement Tonne-kilometres of freight transport for packages paid for by the University within the calendar year, via domestic, long haul and short haul air transit and road vans
Assumptions

Air transit: For freight requiring domestic or international air transport, the main airport nearest the sender and recipient cities is used and passenger kilometres is calculated between the airports (data source: Toitū Travel Calculator)

Road transit for international freight: Distance is estimated by calculating the road kilometres from the sender city to airport as well as road kilometres from recipient city airport to recipient city (data source: Google Maps)

Road transit: Distance is estimated by calculating the road kilometres between the sender and recipient cities (data source: Google Maps)

Data source Freight reports provided by suppliers through Strategic Procurement Manager
ISO standard Category 3: Indirect emissions from transportation / Upstream freight - Paid for by the organisation
GHG Protocol Scope 3

HCFC-22

Parameter  Details 
 Unit Kilogram (kg)
Definition HCFC-22 is a hydrochlorofluorocarbon (greenhouse gas with high global warming potential), generally used for air conditioning
Measurement Kilograms of HFC-22 losses within the calendar year due to usage and possible leakages during top-ups, extraction, transport, storage and/or processing
Assumptions

Where top-up amounts are not provided by a supplier, purchases of gas and refrigerants are reported as losses

It is assumed that purchases are made for top-ups or replacement of gas stocks

Data source Refrigerant/Gas report provided by suppliers through Campus Services Manager or Strategic Procurement Manager
ISO standard Category 1: Direct emissions and removals / Leakage of refrigerants
GHG Protocol Scope 1

HFC-134a

Parameter  Details 
 Unit Kilogram (kg)
Definition HFC-134a is a hydrofluorocarbon (greenhouse gas) generally used for air conditioning 
Measurement Kilograms of HFC-134a losses within the calendar year due to usage and possible leakages during top-ups, extraction, transport, storage and/or processing
Assumptions

Where top-up amounts are not provided by a supplier, purchases of gas and refrigerants are reported as losses

It is assumed that purchases are made for top-ups or replacement of gas stocks

Data source Refrigerant/Gas report provided by suppliers through Campus Services Manager or Strategic Procurement Manager
ISO standard Category 1: Direct emissions and removals / Leakage of refrigerants
GHG Protocol Scope 1

HFC-32

Parameter  Details 
 Unit Kilogram (kg)
Definition HFC-32 is a hydrofluorocarbon (greenhouse gas) generally used for air conditioning 
Measurement Kilograms of HFC-32 losses within the calendar year due to usage and possible leakages during top-ups, extraction, transport, storage and/or processing
Assumptions

Where top-up amounts are not provided by a supplier, purchases of gas and refrigerants are reported as losses

It is assumed that purchases are made for top-ups or replacement of gas stocks

Data source Refrigerant/Gas report provided by suppliers through Campus Services Manager or Strategic Procurement Manager
ISO standard Category 1: Direct emissions and removals / Leakage of refrigerants
GHG Protocol Scope 1

Incineration of clinical waste

Parameter  Details 
 Unit Kilogram (kg)
Definition Clinical or medical anatomical waste sent to a local crematorium for incineration
Measurement Kilograms of anatomical clinical waste destroyed through incineration within the calendar year 
Data source Waste reports are provided by suppliers through Waste Minimisation Specialist
ISO standard Category 4: Indirect emissions from products used by organisation
GHG Protocol Scope 3

LPG stationary commercial

Parameter  Details 
 Unit Kilogram (kg)
Definition LPG refers to liquified petroleum gas
Measurement Kilograms of LPG losses within the calendar year
Data source Refrigerant/Gas report provided by suppliers through Campus Services Manager or Strategic Procurement Manager
ISO standard Category 1: Direct emissions and removals / Stationary combustion
GHG Protocol Scope 1

N2O

Parameter  Details 
 Unit Kilogram (kg)
Definition N2O is the chemical formula for nitrous oxide (greenhouse gas)
Measurement Kilograms of N2O losses within the calendar year due to usage and possible leakages during top-ups, extraction, transport, storage and/or processing
Assumptions

Where top-up amounts are not provided by a supplier, purchases of gas and refrigerants are reported as losses

It is assumed that purchases are made for top-ups or replacement of gas stocks

Data source Refrigerant/Gas report provided by suppliers through Campus Services Manager or Strategic Procurement Manager
ISO standard Category 1: Direct emissions and removals / Leakage of refrigerants
GHG Protocol Scope 1

Natural gas distributed commercial

Parameter  Details 
 Unit Kilowatt hour (kWh)
Definition Natural Gas distributed commercial refers to reticulated gas delivered through a piped gas system
Measurement Kilowatt hours of energy from natural gas purchased 
within the calendar year for buildings within the
operational boundaries of the University
Data source Invoices provided by the suppliers through the Energy Manager
ISO standard Category 1: Direct emissions and removals / Stationary combustion
GHG Protocol Scope 1

Natural gas distributed commercial T&D losses

Parameter  Details 
 Unit Kilowatt hour (kWh)
Definition Losses that occur in the transmission of natural gas between the sources of supply and points of distribution
Measurement Kilowatt hours of losses of energy for natural gas purchased within the calendar year for buildings within the operational boundaries of the University
Data source Invoices provided by the suppliers through the Energy Manager
ISO standard Category 1: Direct emissions and removals / Transmission of energy (T&D losses)
GHG Protocol Scope 1

Paper use - default

Parameter  Details 
 Unit Kilogram (kg)
Definition Paper reams, converted to weight
Measurement Kilograms of paper purchased by the University
Data source Paper reports provided by suppliers through Strategic Procurement Manager
ISO standard Category 4: Indirect emissions from products used by organisation / Purchased goods and services
GHG Protocol Scope 3 Additional

Petrol

Parameter  Details 
 Unit Litre (L)
Definition Transport fuel used for work-related travel (cars, vans, tractors, farm vehicles)
Measurement Litres of mobile combustion petrol used for work-related travel in vehicles owned or leased by the University
Data source Fuel card reports provided by suppliers through Strategic Procurement Manager
ISO standard Category 1: Direct emissions and removals / Mobile combustion (incl. company owned or leased vehicles)
GHG Protocol Scope 1

R-404A

Parameter  Details 
 Unit Kilogram (kg)
Definition R-404A is a zeotropic refrigerant blend (greenhouse gas), used in low and medium temperature refrigeration applications
Measurement Kilograms of R-404A losses due to usage and possible
leakages during top-ups, extraction, transport, storage and/or processing
Assumptions

Where top-up amounts are not provided by a supplier, purchases of gas and refrigerants are reported as losses

It is assumed that purchases are made for top-ups or replacement of gas stocks

Data source Refrigerant/Gas report provided by suppliers through Campus Services Manager or Strategic Procurement Manager
ISO standard Category 1: Direct emissions and removals / Leakage of refrigerants
GHG Protocol Scope 1

R-407C

Parameter  Details 
 Unit Kilogram (kg)
Definition R-407C is a zeotropic refrigerant blend (greenhouse gas), used in air conditioning and heat pump applications
Measurement Kilograms of R-407C losses due to usage and possible
leakages during top-ups, extraction, transport, storage and/or processing
Assumptions

Where top-up amounts are not provided by a supplier, purchases of gas and refrigerants are reported as losses

It is assumed that purchases are made for top-ups or replacement of gas stocks

Data source Refrigerant/Gas report provided by suppliers through Campus Services Manager or Strategic Procurement Manager
ISO standard Category 1: Direct emissions and removals / Leakage of refrigerants
GHG Protocol Scope 1

R-410A

Parameter  Details 
 Unit Kilogram (kg)
Definition R-410A is a zeotropic refrigerant blend (greenhouse gas), used in air conditioning and heat pump applications
Measurement Kilograms of R-410A losses due to usage and possible
leakages during top-ups, extraction, transport, storage and/or processing
Assumptions

Where top-up amounts are not provided by a supplier, purchases of gas and refrigerants are reported as losses

It is assumed that purchases are made for top-ups or replacement of gas stocks

Data source Refrigerant/Gas report provided by suppliers through Campus Services Manager or Strategic Procurement Manager
ISO standard Category 1: Direct emissions and removals / Leakage of refrigerants
GHG Protocol Scope 1

Rental car

Parameter  Details 
 Unit Kilometres (km)
Definition Rental cars booked and paid for by the University
Measurement Kilometres of work-related travel in a rental car, for work-related travel of the University and UniServices, categorised by type of fuel used (diesel, petrol, hybrid, and electric)
Data source Rental Car reports provided by suppliers through Strategic Procurement Manager
ISO standard Category 3: Indirect emissions from transportation / Business travel - Transport (non-company owned vehicles)
GHG Protocol Scope 3

Steam generation

Parameter  Details 
 Unit Tonne (t)
Definition Steam purchased from Auckland District Health Board, converted from kilowatt hours to tonnes (disconnected May 2023)
Measurement Tonnes of steam purchased for buildings within the operational boundaries of the University
Data source Invoices provided by the supplier through the Energy Manager
ISO standard Category 2: Indirect emissions from imported energy / Imported energy
GHG Protocol Scope 2

Taxi

Parameter  Details 
 Unit New Zealand dollars ($)
Definition Taxi travel booked and paid for by the University
Measurement Dollars spent on work-related taxi travel booked and paid for by the University, including reports from suppliers and staff reimbursements data
Data source Taxi reports provided by suppliers through Strategic Procurement Manager, staff reimbursement data provided by Compliance Analyst
ISO standard Category 3: Indirect emissions from transportation / Business travel - Transport (non-company owned vehicles)
GHG Protocol Scope 3

Recycling process

Parameter  Details 
 Unit Kilogram (kg)
Definition Waste disposal recycling refers to aluminium, glass, paper, plastic, and steel cans collected for recycling
Measurement Kilograms of materials put through the recycling process (excludes transport to waste recovery facility; see waste disposal recycling)
Assumptions 2019 waste analysis percentages were used to estimate the portions of waste that were aluminium, glass and plastic for 2020 - 2022 inventories
Data source Waste reports are provided by suppliers through Waste Minimisation Specialist.
ISO standard Category 4: Indirect emissions from products used by organisation / Disposal of solid waste - Not landfilled
GHG Protocol Scope 3 Additional

Waste disposal recycling transport

Parameter  Details 
 Unit Kilogram (kg)
Definition Waste disposal recycling refers to aluminium, glass, paper, plastic, and steel cans collected for recycling
Measurement Kilograms of recyclable materials tranported to an energy recovery or materials reclamation facility
Assumptions 2019 waste analysis percentages were used to estimate the portions of waste that were aluminium, glass and plastic for 2020 - 2022 inventories
Data source Waste reports are provided by suppliers through Waste Minimisation Specialist
ISO standard Category 4: Indirect emissions from products used by organisation / Disposal of solid waste - Not landfilled
GHG Protocol Scope 3 Additional

Waste landfilled

Parameter  Details 
 Unit Kilogram (kg)
Definition Waste disposed at specific landfills and remaining waste that is not recycled, diverted, or composted
Measurement Kilograms of waste sent to landfill
Data source Waste reports are provided by suppliers through Waste Minimisation Specialist
ISO standard Category 4: Indirect emissions from products used by organisation / Disposal of solid waste - Landfilled
GHG Protocol Scope 3

Wastewater for treatment plants

Parameter  Details 
 Unit Cubic metre (m3)
Definition Wastewater sent to domestic treatment plants
Measurement Cubic metres of wastewater sent to treatment plants
Data source Wastewater reports are provided by the supplier through Energy Manager
ISO standard Category 4: Indirect emissions from products used by organisation / Disposal of liquid waste - Wastewater
GHG Protocol Scope 3 Additional

Water supply

Parameter  Details 
 Unit Cubic metre (m3)
Definition Water purchased for buildings
Measurement Cubic metres of water purchased for buildings within the operational boundaries of the University
Data source Water reports are provided by suppliers through Energy Manager
ISO standard Category 4: Indirect emissions from products used by organisation / Purchased goods and services
GHG Protocol Scope 3 Additional

Working from home

Parameter  Details 
 Unit Employee per day (epd)
Definition Full-time equivalent staff member employed at the university
Measurement Estimated employee per day working from home or off campus
Data source Staff poll of senior professional staff leaders (7 September 2022)
ISO standard Category 3: Indirect emissions from transportation
GHG Protocol Scope 3 Additional