Types of water heating systems

Once you have used our water heating systems tool to compare the upfront and running costs of different water heating system types for your situation, here is a summary of other things to consider to help you choose the best water heating system for your needs.

 Water heating systems tool

Electric hot water cylinders

Good for

 Be aware that
  • Households that use low to moderate amounts of hot water
  • Relatively low upfront cost
  • Can be put on a controlled or night-rate electricity supply to get a lower electricity price  
  • Some can have a wetback added to them to use the heat of your woodburner for water heating
  • they are more expensive to run than most other options
  • older cylinders (pre-2002) will need wraps put around them to reduce heat loss

 Electric hot water cylinders

Gas continuous flow

Good for Be aware that
  • if you already use reticulated gas for space heating, and want to continue this
  • homes with small spaces - can be located outside
  • ‘limitless’ hot water.
  • you will have to pay a fixed charge for reticulated gas supply (if you don't already)
  • running costs are high if you use LPG bottles
  • while burning gas is relatively clean, the greenhouse gas emissions contribute to climate change
  • most systems require an electrical supply, so won't work during a power cut
  • though the hot water never runs out, using more than you need is a waste of money, water and energy
  • Condensing gas continuous flow systems are more efficient than conventional gas continuous flow systems.

 Gas continuous flow

Gas hot water cylinder

Good for Be aware that
  • power cuts - they typically don't need electricity to work.
  • the running costs are relatively expensive
  • you will have to pay a fixed charge for reticulated gas supply (if you don't already)
  • while burning gas is relatively clean, the greenhouse gas emissions contribute to climate change
  • condensing gas hot water cylinders are more efficient than conventional gas hot water cylinders.

 Gas hot water cylinder

Heat pump water heating

Good for Be aware that
  • households that use moderate to high amounts of hot water
  • very low running costs
  • can be put on a controlled electricity supply to get a lower electricity price.
  • relatively expensive upfront cost.

 Heat pump water heaters

Solar water heating

Good for Be aware that
  • households that use moderate to high amounts of hot water
  • low running costs
  • some can have a wetback added to them to use the heat of your woodburner for water heating in winter, when solar radiation is lowest.

  • expensive upfront cost
  • when the sun’s energy is insufficient to heat all the hot water you use, an electric or gas backup will ensure you don’t run out of hot water.

 Solar water heating

Wetback

Good for Be aware that
  • if you're using a wood burner for space heating anyway, and have access to free or cheap firewood.
  • adding a wetback means you get less of the fire's heat going into the room
  • this can be an issue for getting building consent for your woodburner - check with your local council.

 Wetback