Resource use and
waste generation in
Aotearoa New Zealand:
filling (some) gaps
An interactive summary of key findings
Overview
Natural resources, such as plants, soil, minerals and metals, provide humans with food and shelter. They heat our homes, move us around, provide recreational spaces and cultural identity, and so much more.
However, the extraction, processing, and use of these resources also creates waste and pollutants, many of which put substantial pressure on the environment. These in turn affect human health and wellbeing and our economy.
The Parliamentary Commissioner for the Environment (PCE) is investigating resource use and waste generation in the New Zealand economy. He is trying to answer two key questions:
- How much natural resource extraction and waste generation is required by the New Zealand economy?
- How could waste and extraction change as our population, economy and environment evolves?
In the initial stage of this investigation, PCE reviewed what was currently known about New Zealand’s natural resource use and waste generation. In this next stage, the PCE commissioned research to fill in identified gaps – this included research on natural resource use, plastics waste, metal needs for the renewable energy transition, soil vulnerabilities and environmental pressures of resource use.
This interactive summary presents key findings from these reports.
New Zealand's natural resource footprint
The goods and services consumed by New Zealanders in 2019 required about 107 million tonnes of natural resources to produce.
Most of this was sand, gravel and crushed rock (26%), grazed pasture in the form of dairy, meat, etc, (12%) and crude oil (8%).
7 tonnes of these total resources are attributed to the organic material that comes from plants and animals, mostly food and wood.
7 tonnes is made up of non-metallic minerals, such as rock, gravel, sand and limestone.
4 tonnes of this is fossil fuels, including coal, oil and gas.
3 tonnes are metallic minerals, such as iron, gold and copper.
How that compares
On a per-person basis our overall natural resource footprint is about average by OECD standards – but roughly twice the size of the footprint of developing countries.
What do we consume?
A set of four basics - food, housing, infrastructure and mobility account for 72% of New Zealand’s natural resource consumption.
Mobility includes transport equipment, passenger and freight services, and the fuel to power them. It included four million tonnes of petrol and diesel in 2019.
Infrastructure includes roads, sewage and waste services. Non-metallic minerals, such as sand and gravel, made up the majority of natural resources used this sector in 2019.
Food accounted for the greatest proportion of New Zealand’s natural resource consumption in 2019. Most of this was ‘biomass’ – products that come from biological sources. Examples include the grass consumed by livestock (12 million tonnes), which then becomes food products, and sugar cane (6 million tonnes).
Housing also uses a lot of sand and gravel and biomass – in the form of wood. Around 7 million tonnes of non-metallic minerals were used in this sector in 2019.
Other categories include energy, personal effects, health and education and communication.
|
Chart note: - To view each category individually, select the key label above the graph. - Hover over the bars for more information. |
Where are our natural resources extracted?
60% of our resources were extracted overseas and imported into New Zealand. The rest came from natural resources extracted from New Zealand.
New Zealand relies heavily on other countries for certain resources, such as crude oil, metal ores, phosphate rock and sugar cane.
Often the environmental impacts of this resource extraction are out of sight for New Zealand consumers.
In total, 130–135 million tonnes of natural resources were extracted in New Zealand in 2019 (excluding water).
Biological products and non-metallic minerals accounted for 90% of extracted materials. Two thirds of this were exported.
How resource use is changing
The natural resources within New Zealand’s imports more than doubled between 1994 and 2019, while those extracted domestically only increased by 25%. This indicates that we are increasingly relying on the rest of the world for our natural resources.
Other research
Soil vulnerability
Many of the biological products extracted from New Zealand depend on soil to grow, but this soil is at risk from erosion (182 million tonnes are estimated to be lost to waterways annually) and contamination from some fertilisers, fungicides and pharmaceuticals.
Source: Ministry for the Environment, Stats NZ, and data providers, and licensed by the Ministry for the Environment and Stats NZ for re-use under the Creative Commons Attribution 4.0 International licence.
Trace element contamination from some agricultural and horticultural chemicals was identified as the greatest risk to the future productive capacity of soils.
Currently, there is limited information about some aspects of the properties and productive capacity of soils that hinders its effective management in New Zealand. These knowledge gaps include the extent and impact of contamination from horticultural chemicals, pesticide residues and microplastics.
Plastic waste
New Zealand imported approximately 1.5 million tonnes of plastic in 2022. Around 400,000 (25%) ultimately became packaging, which has a short use-life and will disposed of relatively quickly.
Most of our imported plastic is embedded in complex products like vehicles or clothing. The use-life of this plastic could be months or years, depending on the product and the owners' use habits.
New Zealand produces about 450,000 tonnes of plastic waste each year. About 15% of that is thought to be recycled (either domestically or abroad) and the rest goes to landfills or into the natural environment.
Metal requirements for green energy transition
In 2023, around 56,000 tonnes of metal were required by New Zealanders for solar and wind generation, battery storage, and electric and plug-in hybrid vehicles. That is projected to increase by 500% to 300,000 tonnes by 2050.
By 2040, it is projected that renewable technologies will produce about 30,000 tonnes of metal waste each year. By 2050, that figure is projected to increase to around 130,000 tonnes.
This waste will contain valuable metals, but the challenge will be whether those metals can be recovered economically or if they be disposed of in an environmentally responsible way.
Strategies to minimise our environmental impact
Currently, New Zealanders use three main technology-based strategies to reduce the impact of resource extraction and use on the environment. Each strategy has its benefits and limitations.
Containment and capture of pollutants and wastes before or as they enter the environment
Many innovations and technologies have been successful in minimising pollution and reducing risks to the environment and human health. However, technology can be imperfect.
For example, even state of the art wastewater treatment plants can’t remove all pollutants and contaminants from wastewater. This can be problematic when residues from pharmaceutical use travel through waste water treatment plants and enter waterways.
Pharmaceuticals like contraceptives contain chemicals, such as the well known endocrine disrupting chemical EE2 (17α-ethinylestradiol). Under long-term exposure, low concentrations of EE2 in waterways can disrupt the sexual development and reproductive performance of fish, which can lead to population collapse (Ho et al., 2020).
Substitution of one resource with a potentially less polluting one
This strategy has been described as, ‘when today’s problems come from yesterday’s solutions’.
One example is the endocrine disrupting chemical BPA (Bisphenol A) which was commonly found in plastic products. BPA can leach out when plastic is used to store hot foods or liquids (de Paula and Alves, 2024). BPA is not only widely found in the natural environment, but in blood, urine and human tissue. BPA has been phased out of many plastic products and substituted with alternative chemicals with similar properties (BPB, BPS, BPF and BPAF). However, subsequent studies have shown that these chemicals are similarly toxic to the environment and humans and as easily spread (Cano-Nicolau et al., 2016; Chen et al., 2016; Huang et al., 2020).
Improved efficiency of existing resource use
Through research and development, resources can be used more efficiently. However, in some cases, efficiency gains may result in more of the resource being used. For example, the improvements in air-conditioning units have made this technology more efficient, cheaper to produce and cheaper to run. This has resulted in more people buying air-conditioning units and running them for longer. As a result, the total amount of electricity used to cool buildings has increased, even though individual air-conditioning units use less electricity.
Will these strategies be enough to help us confront the environmental challenges we face from resource use?
This question and other will be considered in the PCE’s forthcoming report on resource use and waste generation.
Sign up to the PCE mailing list to receive information about upcoming reports.
|
|
Built with Shorthand