May 9, 2024

How Energy Efficient Are Heat Pump Hot Water Systems?

How Energy Efficient Are Heat Pump Hot Water Systems?

As much as we love switching on our homes and the luxury of a long hot shower, we don’t like the stress that comes with quarterly energy bills. Homes consume a large amount of energy for everyday living and with rising energy costs and higher cost of living, excess energy use can really hurt everyday Australian families.

There are a number of factors contributing to energy supply issues as well as increased energy prices including:

  • Shortage of fossil fuels
  • Increased expenses in mining and energy delivery
  • Growing reliance on electrical appliances for everyday living
  • Larger homes, including extra bathrooms
  • Evidence of climate change

All this is influencing governments and homeowners to push for greener energy supply across Australia and one contender for a greener home is a heat pump.

What Is A Heat Pump Hot Water System?

A heat pump is a specialised type of solar energy solution that allows your home’s hot water to be warmed through environmental heat transfer. A heat pump allows you to replace your existing electric hot water heater with one that uses significantly less energy to supply the same amount of hot water to your home. Instead of harnessing sunlight, your heat pump accesses the warmth in the air and ground around it, making it suitable for Australian homes that don’t have adequate rooftop space for solar, or who can’t afford the high expense of a solar setup.

How Heat Pump Systems Work

The science of a heat pump is a little like a fridge. A refrigeration cycle is used to extract heat from the surrounding air and transfer it to your water tank ready for hot water use. Unlike many refrigerant chemicals that are toxic to the ozone, heat pumps use the chemical R134a, which is safe and doesn’t add any greenhouse emissions.

Once the liquid R134a evaporates to gas it creates pressure in a chamber and enough heat to rapidly bring your insulated stored water to high temperature.

The refrigerant chemical is highly effective in climates that experience annual temperatures between 4.4º to 32.2ºC degrees, however, it’s perfectly fine if you experience extreme temperatures of -10°C to 46°C from time to time as the liquid is able to evaporate at very low temperatures (-26C).

Heat Pump Pros & Cons

Heat pump systems use around 60 to 75% less electricity than a standard electric hot water system as it only requires electricity to operate the fan and compressor, the rest is left to natural heat energy.

There are a number of benefits heat pumps offer over solar solutions:

  • Fully operational all day and night
  • Is able to work efficiently during storms and cloudy weather
  • Lower installation costs- in most cases can be connected to your standard electric hot water inlets and plumbing
  • Government rebates can help cover almost all the costs

You’ll need to make sure you have adequate space around the unit for fresh air flow (at least 28.3 cubic metres). Keep in mind that the air expelled from the unit is cool, so confined spaces will become cooler with use and might not be able to capture enough heat energy to work efficiently. Operating noise can be a factor with some heat pump models so you’ll need to select the right unit if it will be located close to bedrooms or neighbours.

Heat pumps are significantly cheaper to buy and install than solar panels and in most cases can be easily positioned in the same place and use the same plumbing as your existing electric hot water system. With government solar rebates softening and natural gas being phased out, heat pumps are a practical, efficient and economical choice for Australian homeowners. Ask a qualified plumber to assist in assessing your home’s suitability for a heat pump hot water system and be sure to check with them about current rebates available in your local area that can bring your new heat pump purchase down to almost nothing.