Energy is an essential part of almost all our industrial, commercial, transport, and household activities. A secure and sustainable energy supply is therefore vital to ensuring New Zealand’s continued economic and social well-being.
Renewable energy sources
New Zealand has access to a diverse range of renewable energy sources (see Figure 5.1). The water in our rivers is harnessed to provide hydro-electric generation, with well-developed systems in the Waikato River catchment in the North Island and the Waitaki River and Clutha River catchments in the South Island.
Since the 1900s, geothermal energy has been used to generate electricity in New Zealand, with high-temperature geothermal reservoirs concentrated in the Taupō Volcanic Zone. New Zealand’s first geothermal power station was commissioned at Wairākei in 1958.
Further contributions to New Zealand’s renewable energy supply come from wood, biogas, the sun, and wind. The marine environment has the potential to contribute to New Zealand’s energy needs in the future – wave and tidal energy can be harnessed to generate renewable electricity. Some industrial processes burn waste materials, such as used oil and wood waste, to create energy (see box ‘Local action: waste-to-energy later in this chapter for more information).
There are potential limitations with some renewable energy sources, such as hydro and wind. While New Zealand has a lot of potential capacity, public opinion is divided on further growth in the number of hydro-electric power stations on rivers and the number of large wind farms.
Non-renewable energy sources
Reserves of natural gas and limited quantities of oil are extracted from gas and oil fields in the Taranaki region. The balance of New Zealand’s oil supply is imported. Coal deposits exist throughout New Zealand, although most production is from mines on the South Island’s West Coast and from the Waikato region.
Environmental and human health impacts
The production and use of renewable and non-renewable energy impacts on the environment as listed in the examples below.
The extraction and processing of fossil fuels affects adjacent air, land, and sea.
The burning of fossil fuels contributes to:
- climate change through a build-up of greenhouse gases, primarily carbon dioxide
- localised air pollution due to particulate emissions.
Construction of storage lakes and dams for hydro-electric generation alters the surrounding land, ecosystems, and settlements.
Wind farms have a visual impact on the landscape and selecting suitable sites for wind power developments can be difficult because such sites are often exposed locations on prominent ridgelines. The potential noise impact of wind farms is also a consideration in the assessment of environmental impacts.
The by-products of fossil fuel energy use include harmful particulate emissions, which can impact on human health causing irritation of the eyes, throat, and lungs. For people with existing respiratory conditions, such as asthma or bronchitis, inhaling particulates can exacerbate the condition (see chapter 7, ‘Air’ for more information about particulates).
As our population grows and our lifestyles change, so do our energy needs. Over the past 10 years our consumption of goods and services has increased (see chapter 3, ‘Household consumption’), and so has our consumption of energy.
Text description of figure
This map illustrates the general location of New Zealand's major energy sources. Wind power is generated in the lower North Island and Southland regions. Coal resources are mined from the Waikato region in the mid to upper North Island and from Southland and the West Coast of the South Island. Hydropower is generated in the Central North Island region and the lower half of the South Island in South Canterbury and Central Otago. Onshore and offshore gas and oil resources are located in the Taranaki region on the West Coast of the Central North Island. Geothermal power is generated in the Central North Island. New Zealand's major thermal power station is located at Huntly in the mid to Upper North Island. An oil refinery is located at Marsden Point in the Upper North Island. New Zealand also imports oil and oil products from overseas.