Heat pumps are the cheapest form of heating and unflued gas heaters are the most expensive. Natural gas is the cheapest form of central heating.

Electricity


Electric power socket

A heat pump is the cheapest heating option to run. You can have a heat pump retro-fitted – but to run efficiently it must be the right capacity for the house and it must be installed correctly.

Discounted night rates make nightstore and underfloor heating comparatively cheap, although you may need an additional meter (which would be an extra cost).

Plug-in heaters are the most expensive form of electrical heating. Modern well-insulated homes suit convection or oil-column heaters because the warm air won’t leak away. For poorly insulated older houses with high ceilings, radiant heaters are likely to be effective – you can feel their heat more directly. However, they shouldn’t be used in bedrooms or in rooms where there are young children.

How clean?

Our electricity comes from a combination of renewable (wind, hydro and geothermal) and non-renewable (gas and coal) sources – so it's only a semi-clean fuel. But in your home, nothing is cleaner. Despite the inexorable rise in the price of electricity, electric heating provides a clean and easy way to heat your home.

More information

 

Firewood


Firewood

A woodburner is a cheap way of heating your home – if you can get free firewood. We’ve used prices for pine in our Fuel prices compared table because it was the cheapest and most widely available wood in our November 2013 firewood survey. Delivery is usually free but this depends on how far away you are from the supplier.

We haven’t calculated the cost of burning wood in an open fireplace. Fireplaces are inefficient (heat is lost up the chimney) and they cause massive pollution for the heat they do produce.

Tip: Buy early – during spring or early summer – and phone around for prices. We found some good deals in our firewood survey.

How clean?

Along with wind and hydro, wood is one of the few sustainable carbon-neutral home-heating options. But to get the most heat (and the least pollution), it must be burned hot and in a specially designed firebox. The firewood must also be dry and the pieces not too big (less than 11cm in diameter).

Some woodburners can be used to heat wetbacks but this reduces their efficiency and may also overheat the water.

More information

 

Wood pellets


Wood pellets

These are used in pellet burners and also in boilers for central heating. They’re sold in 15kg or 20kg bags. Our price survey found big variations – and prices were usually lower in the South Island.

Pellet burners cost more to run than woodburners but they have their advantages. They produce less atmospheric pollution and the pellets are carbon neutral because they’re made from waste wood (compressed sawdust and wood shavings).

A pellet burner is one of the cheaper forms of central heating. It’s also the only type of central-heating fuel that’s a renewable resource.

More information

 

Natural gas


Natural gas flare

It’s cheaper to run your flued heater or central heating on natural gas rather than on LPG. Unfortunately, reticulated (piped) natural gas is available only in the North Island.

Prices for natural gas can fluctuate, as they do for LPG and diesel. They’re world commodities and subject to rapid changes out of the householder’s control.

Tip: Dual-fuel discounts for getting your gas and electricity from the same provider usually mean it’s cheaper than using a separate provider for your gas. Visit Powerswitch to find the best deal.

How clean?

Natural gas is clean-burning for pollutants, but it's a fossil fuel. Burning it adds the greenhouse gas carbon dioxide to the environment.

More information

 

LPG


LPG cyclinders

Prices for the 45kg cylinders of LPG delivered to your door include the cost of delivery – which means people in rural areas pay more.

Running an unflued heater on 9kg bottles is the most expensive way to heat your home. It also presents a health and safety hazard: unflued heaters produce CO2 (carbon dioxide) and create condensation.

Warning: If a fault develops in an unflued heater, it can emit poisonous carbon monoxide. This can build up in a room and become a significant health risk for children, pregnant women and people with asthma or heart disease – and high levels of it can kill anyone. An unflued heater should only be used in rooms with good ventilation and should never be used in bedrooms.

How clean?

Like natural gas, LPG is clean-burning but adds carbon dioxide to the environment.

More information

 

Diesel


Diesel tanks

Diesel boilers are often used for central heating: they heat water which then circulates through water-filled radiators or underfloor heating ducts. Stand-alone diesel heaters are also available – they’re designed to look like a wood fire.

Diesel prices can change rapidly depending on the world price. In February 2014 the price of diesel was nearly 2 percent lower than its February 2013 price. But during those 12 months there was a 10 percent difference between the highest and lowest prices – and these occurred within 3 months of each other.

How clean?

Diesel is an atmospheric pollutant and a non-renewable resource.

 

The sun


It's free, and the most environmentally-friendly home heating option available. You'll need large north-facing windows to allow the sun to shine in during the day, a large thermal mass such as a concrete floor to store the heat, and insulation so the heat isn't lost too quickly at night. And you'll probably still need other heat sources for the coldest days.

If you're designing a new home, incorporating some passive solar heating into the design may not cost very much at all. It may also be possible to include some solar features when you're renovating, but it's harder.

More information

Join now

Get full access to all Consumer reports for as little as $1.85 a week

  • Over 500 reports plus interactive tools and calculators
  • Independent advice from NZ's trusted source of information
  • Join over 65,000 members who help us get all NZers a fairer deal

Join Consumer now and make your decisions easy on a huge range of products and services

  • Over 500 reports, plus interactive tools and calculators
  • Independent advice from NZ's trusted source of information
  • Join over 65,000 members who help us get all NZers a fairer deal

from just $28

Join now
Read what our members say