Heat to a healthy temperature

The World Health Organisation recommends indoor temperatures of at least 18°C, or 20°C for houses with young children, elderly people or ill people.

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Heating makes up around a third of your household energy bills. This means that you can make some serious savings by being smart with how you heat your home.

Ways to save

  • Invest in efficient technology

    Make energy efficiency a priority when buying a new heating appliance, because this will make it much cheaper to run. Heat pumps typically have a lower overall lifetime cost than other options, particularly for general living areas and any areas which require frequent heating or cooling.

    Make a good investment

  • Use your systems efficiently

    Being smart about how you heat and cool your home will save you energy and money. Set up your home to keep the warmth in winter and stay cool in summer, and check our tips for using heat pumps, electric heaters and fans efficiently.

    Keeping warm and staying cool

  • Insulate and block draughts

    Insulation makes a big difference to keeping your home warm and healthy. Start with the ceiling insulation, then the accessible spaces under your floor. Blocking drafts and preventing heat escape through windows are effective ways to keep cosy in winter.

    Insulate your home

Make a good investment

As well as upfront and running costs, here are some other considerations to think about when you choose a new heating and/or cooling system.

  • Renewable energy – Choose a heater that uses renewable energy, like wood, wood pellets or electricity (which is on average about 80-85% renewable).
  • Energy efficiency – A more efficient system, with heat pumps being the most energy efficient for space heating, is cheaper to run over time, so is usually worth the upfront investment over less efficient options.
  • The right size for you – Choose the right-sized heater for the room — too small and it’ll struggle, too big and you’ll pay more. Tenancy Services Heating Assessment Tool(external link)
  • Opportunities when building or renovating – Choosing all electric options over gas for your heating, hot water and your stove top/oven means that you can avoid the ongoing fixed costs of a daily gas connection charge, or LPG bottle rental.

Comparison of home heating options

  • Wood and pellet burners

    Wood is a low emissions and renewable fuel source. Wood fires and pellet burners are typically cheaper to run than gas heating, but more expensive than heat pumps.

    A building consent is required for the installation or replacement of a wood burner, and many local councils have specific regulations because of air quality concerns.

  • Gas heaters

    Gas heaters can run on mains natural gas (North Island only) or bottled liquid petroleum gas (LPG). Both are fossil fuels, so directly generate greenhouse gas emissions. LPG is the most expensive option in terms of fuel costs. For piped gas, there are fixed charges to consider as well as usage costs.

    Avoid unflued gas heaters – also known as cabinet heaters, these tend to be the most expensive type of heating and release toxic fumes and moisture into your house.

Choose the best heat pump

When buying a heat pump/air conditioner, make energy efficiency a priority. This will help you save money on running costs.

In store, you can compare heat pumps by looking at the Zoned Energy Rating Label, which shows the energy efficiency of different models in hot, average or cold climates.

And online, the Gen Less Efficient Appliance Calculator allows you to compare the efficiency of heat pumps based on your climate zone.

Keeping warm

  • A really good heater in the room you use most makes a world of difference to health and comfort. A smaller, cheaper one is fine for rooms you use less, like a spare bedroom or study.
  • Making sure your home is properly insulated will mean your heat pump or heater won't have to work as hard and you won’t pay as much in bills each month.
  • Use a timer to warm the room before you need it, and switch off when you don't need it. You can buy a separate timer plug if your heater doesn’t have one built in.
  • Make sure your thermostat is not set too high – 20°C or 21°C maximum – this keeps your home warm and dry, while saving power.
  • Use and maintain your heater as recommended by the manufacturer.
  • Put portable heaters on the cold side of the room or near a window – it helps to distribute the heat.
  • Hold onto your heat – shut doors and curtains, and block drafts.
  • Stay safe – keep heaters away from curtains and anything else that could catch fire. Plug in only one heater per socket.

Staying cool

  • Keep out the sun by shutting curtains and blinds.
  • Open doors and windows in different rooms to move air through your home.
  • Fit security latches to leave windows open while you’re out.
  • Plant deciduous trees to shade your house in summer. They’ll let sun through when they lose their leaves in winter.
  • Install external window shades – such as blinds, awnings or louvres. Eaves or roof overhangs above north-facing windows block summer sun.
  • Use fans – table-top, floor and ceiling fans use a lot less energy than air conditioning. If you have a heat pump, try the fan-only setting with your windows open.

 

If using air con:

  • Try the dehumidifying mode – it uses less energy than full conditioning.
  • Cool one room – it's what most are made to do.
  • Shut doors and windows.
  • Set the thermostat to a minimum of 24ºC during the day – a lower setting won't make it work faster.
  • The best time to use air conditioners is when you are trying to sleep. The ideal temperature to set the thermostat at is 20°C.
  • Don't use 'auto' as it may switch to heating.
  • Clean the filter with a vacuum cleaner or warm water every couple of weeks.

Electric fans use a lot less energy than air conditioning. If you have a heat pump, you can use the fan-only setting with your windows open.

Choose the right electric heater for your room

Plug-in electric heaters are good for smaller rooms like bedrooms and studies. Whether they’re convection, panel, oil column, fan, micathermic, radiant, infrared..., they all convert our 80-85% renewable electricity into useful heat with the same efficiency.

They key is to get the right size. If the power rating or wattage of the electric heater is too small your heater will struggle, if it’s too big, you’ll pay more. Go for one with a higher wattage and a thermostat. The thermostat will regulate the temperature in the room by controlling the power supplied to the heater. The higher wattage combined with the thermostat helps you get to a comfortable temperature quickly without wasting energy.

  • Do a healthy home check

    Start by assessing your home to find out where you can make improvements. You can do a healthy home check yourself online, or a certified advisor can visit and assess your home, and tailor an improvement plan. Many offer their services free of charge.

  • Insulation and heater grants

    Warmer Kiwi Homes is a government programme that provides grants for lower income homeowners covering up to 90% of the costs to purchase and install insulation and an efficient heater. Use the Warmer Kiwi Homes tool to find out if your home is eligible.

It pays to go electric

Powering your home with efficient, electric appliances can save you thousands in energy costs – and slash your carbon footprint.

We’ve done the math on key household energy uses such as heating, water heating, cooking and driving. The numbers show that the most efficient electric options make sense financially – both in terms of monthly running costs and overall lifetime costs.

Discover how your household might stand to benefit from going electric.

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