Water heating systems

Tips for a new system

As well as upfront and running costs, consider these when you choose a new system.

Water heating systems tool(external link)

  • It’s a renewable energy opportunity. There are options to heat your water with our 80% renewable electricity, sustainable wood energy (wetbacks) or the sun.
  • Energy prices vary by area and supplier. Use our water heating systems tool to compare running costs of various options at your place.
  • Get the right size. The number of people in your house, the number of showers and baths, and whether your system feeds the dishwasher or washing machine will have an impact.
  • Take opportunities when building or renovating. Group together spaces that need hot water– bathroom, kitchen, toilets and laundry. There’ll be less hot water left sitting in pipes, and it’ll reach your taps more quickly.

Heat pump water heaters

These can be expensive to buy but are extremely efficient and use our highly renewable electricity.

  • Good for households with moderate to high hot water use
  • Lower running costs
  • Can give you underfloor heating or help heat a hot tub, spa or swimming pool
  • Can be put on a controlled electricity supply to get a lower electricity price
  • Less heat goes into the room – keep this in mind when choosing the right size
  • Not suitable for all situations or hot water systems – get advice from a plumber

Solar water systems

Solar panels on your roof absorb the sun’s energy and transfer it to the water stored in your hot water cylinder – but you probably need a back-up.

  • Good for households with moderate to high hot water use
  • Low running costs
  • Can meet 50-75% of your hot water needs
  • Integrates well with a wetback wood burner in colder months
  • Higher upfront cost
  • Needs an electric, gas, wetback or other booster for when hot water use outstrips supply
  • Not suitable for all properties

Wetbacks

Many wood or pellet fires, ranges or burner systems can have wetbacks fitted, making the most of a plentiful, renewable biofuel.

  • Use renewable wood energy
  • Great if you already have a wood burner
  • Less heat goes into the room – keep this in mind when choosing the right size
  • Not suitable for all situations or hot water systems – get advice from a plumber
  • Many councils have clean air requirements for urban areas – check what wetbacks you can install with your council

Gas hot water systems

Natural gas and bottled LPG are fossil fuels, so generate greenhouse gas emissions. There are cylinder and continuous flow options – the most efficient is a condensing gas continuous flow system.

  • Continuous flow systems can be located outside
  • Cylinder systems keep working in a power cut
  • Fossil fuel releases greenhouse gas emissions
  • Fixed charges for main gas supply
  • Higher running costs for LPG bottles
  • Continuous flow systems may not work during a power cut