CARBON CALCULATORS
For individuals, families, business and others interested in better understanding the environmental impact that their activities have in terms of greenhouse gas emissions – generally with the intention of seeing if/how they might be reduced - there are a number of tools that are available.
A “Carbon Footprint” is often used to provide a measure or index value for the total greenhouse gases (GHGs) generated and added to the atmosphere by our lifestyle and activities but they are also available for objects such as buildings or business undertakings. The value is usually expressed in tonnes of CO2-equivalent (CO2e).
New Zealand’s per head emissions depend on what is considered; Our overall GHG emissions are ~15 tonnes CO2e per person taking all GHG into account but our CO2 specific emissions are around half that figure - not surprising when around half our total emissions are from methane. [These figures are gross emissions and do not take into account the removal of GHG primarily by forestry an action which lowers our emissions to a net figure - but the utilization of this measure helps avoid the necessity to change our behaviours and actively reduce emissions as we can in theory achieve the same result (lower emissions) by planting more trees but in practice this approach while have short-term value, is flawed).
However it is stated though, the per capita figure is high - the global average figure is 4 - 6 tonnes per person
Many carbon calculators are free to use and different calculators can require different information to be inputted depending what purpose the calculator in intended for. For more detailed outputs, expect to provide more information (eg electricity use).
These calculators typically ask for data on energy use (electricity, fuel), travel (flights, driving), waste, and sometimes supply chain activities, using New Zealand-specific emission factors to provide an estimate of your carbon footprint
Many calculators provide information that can be used to guide decisions on what steps can be most usefully undertaken in your journey to reduce missions.
Depending on the purpose, the calculation of a carbon footprint, need not be a complicated exercise. The best example I have seen of a very simple but useful calculator is in a book: “Runaway Climate” by Steven Earle [New Society Publishers 2024]. In this book (Figure A.6, page 174), the author provides a very quick simple way (in tonnes CO2e) to estimate your personal annual carbon footprint using:
The size of your house
The type of car and the mileage you drive
The number of flights
The number of meat meals eaten weekly
For other consumables, the amount spent
Unfortunately I have not yet been able to determine the New Zealand equivalents for the housing emissions.
One calculator that I have used that is easy and rapid is the Swedish ClimateHero Carbon Calculator
Some free New Zealand calculators are listed below:
Developed by the Sustainable Business Network (SBN) and business.govt.nz in collaboration with an number of other organisations, this is online tool is designed to make it easy for smaller businesses to measure and reduce their carbon footprint.
FutureFit began as a collaboration between Wellington City Council and Auckland Council and has since extended to partner with GenLess
Tadpole Consulting provide a free downloadable Excel based tool that can be used to calculate the greenhouse gas (GHG) emissions arising from household or business activities.
Ekos Carbon Zero Business Calculator Lite
This calculator can be used to to estimate your carbon footprint.
The Ministry for the Environment has published this guide for Aotearoa New Zealand-based organisations wishing to measure and report their greenhouse gas emissions.
There also are some construction and building calculators available:
From BRANZ: Life cycle assessment and carbon footprint calculators:
LCAQuick: Life cycle assessment tool
A free tool developed by BRANZ that helps architects, designers and structural engineers make sustainable design decisions. It evaluates the carbon footprint and other environmental impacts of a building design.
Allows users to assess potential environmental impacts for commercial building design concepts.
CO₂MPARE provides summary carbon footprint and other data and information about reference residential and office buildings that BRANZ has evaluated.
Provides calculated carbon footprints per square metre for residential roof, wall and floor constructions.
From the New Zealand Green Building Council: