Deciding which Energy Supplier to use

To find out which energy supplier could provide you with the best service go to the Consumer Power Switch website to look up the options available to you.

You can also:

  • Contact your energy supplier with any concerns you have about how their energy is generated. If you have a choice of energy suppliers, choose not only on the basis of cost savings but also on how their energy is generated.
  • Ask yourself if you really need electrically powered luxury items now, if it means going without in later years.
  • Read, be informed, think critically, act wisely and consume less energy.
  • Join environmental groups that are concerned with and working towards positive change on energy issues.
  • Contact the Hamilton City Council to discuss energy issues and how they can help.
  • Talk with your local MP on energy issues that you feel strongly about and find out the latest government policies on energy.

In New Zealand we have access to a variety of energy sources.

Fossil fuels, that are derived from plants and animals that lived in prehistoric times, hydro-electricity (generated from falling water) and geothermal power (using the earth's own natural heat in areas of volcanic activity) make up most of our current energy sources.

Other sources of energy available to us are: firewood, wind, solar energy and bio-gas from rotting vegetation, to name a few. New Zealand is self sufficient in all energy forms apart from oil.

Renewable Energy

Renewable energy is any energy resource that is essentially inexhaustible; if we manage it wisely it will support us indefinitely.

New Zealand is fortunate to have large amounts of renewable energy available. This is because of our geographical location, our climate, and New Zealand's low population density.

The key benefits of renewable energy sources are that they provide long-term energy without creating pollution problems. Renewable energy is, therefore, considered to be more environmentally sustainable.

Renewable energy is likely to become the energy of choice for the 21st century especially as non-renewable sources of energy continue to decline, and energy shortages continue to occur.

Hydro Power

Between 60-70% of all of New Zealand's electricity is supplied by hydroelectricity.

Hamilton gets most of its hydro electricity from the Waikato River. The 425km long river is home to eight dams and nine power stations.

Water originating from Lake Taupo takes some 18 hours to flow down the Waikato River and arrive at Karapiro, the last station on the Waikato hydro system.

Geothermal

New Zealand has seven geothermal power stations. Five are in the Waikato Region. The Waikato region also provides 90% of the primary geothermal energy extracted in New Zealand.

Commissioned in November 1958, the Wairakei plant was the first in the world to harness hot geothermal water for the production of steam. It is situated above a mass of highly pressurised hot rock and water.

The boreholes at Wairakei, which tap into the geothermal field, are up to 2.2 km deep. Of the geothermal energy extracted, only 10% is converted to a useable form. The rest is re-injected or disposed of into the environment as heat. 

Wind Power

Wind energy is the fastest growing form of generation in New Zealand. Wind turbines are becoming more and more a feature of the New Zealand landscape, seen on various skylines across the country.

They are designed to produce thousands of kilowatts so, even though they may only be able to work to full capacity 40% of the time due to fluctuating wind speeds, the amount of energy being produced when they do is huge.

New Zealand's future wind farms will have a capacity and annual energy output on par with some of the country's hydro power stations.

Landfill Gas

Landfill gas and bio-gas are gases that are composed mainly of carbon dioxide (CO2) and methane (CH4), and are produced from decaying vegetation and other organic materials.

Methane gas emitted from landfill sites can be used to generate electricity for our houses. Bio-gas, produced from animal manures, sewage treatment plants or engineered digesters, can be used to provide energy also.

Over a 10-year period, it is possible for 1 tonne of rubbish to produce 100 times it's own weight in bio-gas.

In many cases methane is produced naturally at landfill sites and lost to the atmosphere adding to the greenhouse effect. The process of burning landfill gas, a methane gas mix, for energy has two benefits. It provides us with energy and it reduces the effect of greenhouse emissions by converting the methane to carbon dioxide.

Hamilton is an excellent example of the use of both natural gas and bio-gas at its sewage treatment plant. This is the only New Zealand site where natural gas is blended with bio-gas and used to power generators.

This project was one of several that have arisen from Hamilton City Council's energy management programme which has helped Council and the community save money.

Solar Power

Solar power is one of the cleanest methods of energy production known. Solar panels simply convert the energy of the sun into energy we can use, there are no harmful by-products or threats to the environment.

If solar energy was used to its full extent it could save you between 50 - 80% of an average household energy bill.

In November 2007 Hamilton City Council announced that it will help encourage solar water heating by waiving building consent fees. Hot water accounts for around $800 of an average household energy bill. 

A well-designed and installed solar water heating system can save up to 75 percent of a household's annual hot water bills. Solar water heating systems, including the cylinder, typically cost between $4000 and $8000 installed. 

Biomass (Woody) Power

Woody biomass resources include waste materials from forestry operations, residues from wood production processes and purpose-grown wood plantations. Biomass provides about 11% of the world's primary energy supplies. 

Large quantities of industrial wood waste are used to generate heat, steam and electric power in developed countries. Bio-energy systems often use biomass that would not otherwise be able to be sold. Some plants, like Kinleith, generate their own power and heat from wood, and sell some power to the grid.

New Zealand is ideal for biomass production because of its very low population density, low temperature climate and fertile soils. With the development of biomass production and a good handling system, there is potential for delivering cost effective woody biomass as an energy source.

Non-Renewable Energy

Non-renewable energy is energy that is unable to be replaced or is replaced very slowly, over thousands of generations by natural processes. They are called non-renewable because once burnt or used, they are gone forever.

Primary examples of non-renewable energy resources are the fossil fuels – oil, natural gas and coal. All three were formed from organic material many hundred millions of years ago, before and during the time of the dinosaurs; hence the name fossil fuels.

Each type of fossil fuel represents a different layer deep in the earth, which has been heated up by the earth's core. The deeper the organic matter goes the hotter it gets.

Natural Gas

When it comes to fossil fuels natural gas has to be one of the best non-renewable forms of energy. It's easy to transport, easy to use and compared to most fossil fuels it burns very cleanly without producing smoke or ash.

Natural gas is formed from the organic matter that became the hottest of all the original forms of fossil fuels which means it has to be extracted by drilling deep into the earth. It is then pumped up to the surface and piped directly to consumers, or bottled and sold.

For decades New Zealanders have been using natural gas as part of our energy supply. We currently depend on natural gas for 30% our energy needs.

Petroleum (Oil)

Up until now we have mainly focused on energy in terms of electricity and heating. However now our attention turns to New Zealand's biggest user of energy. 40% of our energy goes into transport and this is the fastest growing user of energy.

Most of our transport runs on oil. Oil is a very important energy source in society. It is used for transport, manufacturing, asphalt, and is the backbone of the synthetics industry.

The Transport booklet, your household guide to improving your health, saving money and getting around Hamilton better, provides comprehensive information on how to use less of this form of energy.

It includes tips on how to drive your car more efficiently and how to set up a carpool arrangement to share petrol costs with others and reduce vehicle usage. It also includes information on Hamilton's buses, and incentives and tips for cycling and walking. Call 838 6483 for a copy of this booklet.

Coal

Coal makes up 37% of the world's electricity, with extensive reserves in almost 100 countries. Coal currently only provides 5% of New Zealand's electricity.

At current rate of usage, there may be enough coal to last over 200 years BUT as the world's population grows, our demands for energy grow. We may run out well before then.

Coal is the fossil fuel nearest the surface of the earth. It is formed from peat when it is put under pressure. Coal is extracted either through open cast mines (big open pits) or through deep shaft mining where a shaft is dug into the ground and the coal is then tunnelled out. 

The issues with fossil fuels

The two major issues associated with the use of fossil fuels are:
  • The potential depletion of fossil fuels in the near future.
  • Their contribution to global warming and the greenhouse effect when burnt, and while energy is essential for life, there are also pollution problems associated with burning fossil fuels and biomass. Power stations and other industries that burn fossil fuels release carbon dioxide (CO2 ) and nitrous oxide (N2O).

The Huntly Power Station produced about 3.26 million tonnes of carbon dioxide in 2001 in converting coal into electricity.

The accumulation of these gases in the earth's atmosphere is commonly called "the greenhouse effect". A layer of gas forms trapping heat inside the atmosphere, thereby acting like a giant glass ceiling similar to a glasshouse (greenhouse).

It is believed that this is what is causing the atmosphere to slowly warm up and this is having an impact on the climate, and the weather we experience each day.

Page reviewed: 15 Apr 2016 3:32pm