Save money on hot water

Save money on hot water

You probably know that water heating makes up a big part of home power bills.

Here are a few easy strategies to help cut back on power consumption in this area:

  1. Reduce your hot water usage by fitting low-flow showerheads and flow control aerators 
  2. Improve the efficiency of your hot water heating by insulating hot water cylinders and pipes, and considering our three simple steps to better hot water retention.
  3. Have a shower instead of a bath, and have shorter showers
  4. Do your laundry in cold water
  5.  Use the eco-settings on your dishwasher
  6. Fix any dripping taps.

Different options also require different investments. Cheaper options may include wrapping and insulating your hot water cylinder and pipes. Options that cost more include installing more efficient hot water cylinders, or even using alternative power sources such as boilers and heat pump water cylinders.

“Reducing the amount of hot water you use can impact your power bill as much as, or more than, improving the efficiency of your water-heating equipment, often at a lower cost.” – Harley, Bruce (2012) Insulate and Weatherize, For Energy Efficiency At Home, Hot Water, 152

Low-flow showerheads

Consumer.org reports that New Zealand households can save up to $100 a year in hot water bills with low-flow showerheads.

These showerheads do not compromise the quality of your shower. They vary in cost between $70 and $350.

Here’s some useful installation advice 

Community Energy Action recommends monitoring your flow rate with a stopwatch and a 10-litre bucket. If the bucket fills in less than a minute at your normal showering temperature, you may like to install a more efficient showerhead.

Insulating hot water cylinders and pipes

Energywise reports that hot water cylinder wraps cost around $60 at most hardware stores. Pipe insulation, or ‘foam lagging’, for pipes inside your hot water cylinder cupboard cost around $5 per metre. (This measure is most effective for systems installed before 1992).

Insulating your hot water heater can help reduce standby heat loss by half. Find more information on how to insulate your electricity powered hot water cylinders 

Smarter Homes advises that a hot water cylinder wrap could save you up to 1 kWh/day, which means it could pay for itself in a year.

Three simple steps to better hot water retention

Try following these three simple steps to improve hot water retention in your home, and in doing so save money.

  1. Reduce temperature: Check to see if you can reduce the temperature of your hot water cylinder to 60 degrees Celsius — any less could result in harmful bacteria forming. Turning down the thermostat reduces ‘conductive heat loss’ (or standby loss).
  2. Halve tap flow: Inspect your taps and repair any drips. You can also ease the tap’s flow with ‘flow control aerators’. These cost around $10 per tap, and halve water flow without losing pressure 
  3. Watch the overflow pipe: Check your overflow pipe often to make sure it’s not dripping. Most often located on the roof, a leaking (or steaming) overflow pipe means your hot water cylinder is overheating (or the pressure is too high), and is dumping hot water as a safety measure. Watch a video about repairing an overflow pipe here — but it’s probably best to call a plumber.