With electricity prices rising and household budgets under pressure, one of the most common questions homeowners ask when considering a new heat pump is:
How much will a heat pump actually cost to run?
It's a reasonable question. While heat pumps are well known for being an energy-efficient way to heat and cool New Zealand homes, the actual running cost can vary significantly from one household to another.
The size of your heat pump, outdoor temperature, insulation, electricity tariff, temperature setting and even how you use your system can all influence how much electricity it consumes.
At Bay of Plenty Heat Pumps, we're certified Mitsubishi Electric heat pump installers servicing Tauranga, Mount Maunganui, Papamoa and the wider Bay of Plenty. Here's what you need to know about heat pump running costs and how to get the most efficient performance from your system.
Are Heat Pumps Expensive to Run?
Generally, heat pumps are considered one of the most energy-efficient forms of electric home heating.
Unlike a conventional electric heater, which converts electrical energy directly into heat, a heat pump primarily uses electricity to transfer heat from one place to another.
During winter, it extracts available heat from the outdoor air and transfers it inside. During summer, the process can be reversed to remove heat from your home and provide air conditioning.
This ability to move heat rather than simply generate it is what makes modern heat pumps so efficient.
However, an efficient appliance can still consume unnecessary electricity if it's incorrectly sized, poorly maintained or used inefficiently.
What Determines How Much a Heat Pump Costs to Run?
There isn't a single hourly running cost that applies to every heat pump.
Two neighbouring Tauranga households could have similar heat pumps but experience very different electricity consumption.
Some of the biggest factors include:
- Heat pump size and capacity: A larger system will generally have greater maximum power requirements, although correct sizing is more important than simply choosing the smallest unit.
- Room size: Larger rooms and open-plan living areas require more heating or cooling.
- Insulation: A well-insulated home retains heat for longer, reducing the workload on your heat pump.
- Windows and glazing: Large areas of glass and single glazing can contribute to greater heat loss.
- Outdoor temperature: The greater the difference between the indoor and outdoor temperatures, the harder the system may need to work.
- Your temperature setting: Asking your heat pump to maintain an unnecessarily high indoor temperature in winter can increase electricity consumption.
- How long you use it: Naturally, a heat pump operating for eight hours will usually consume more electricity than one operating for two.
- Heat pump efficiency: Modern inverter heat pumps can adjust their output according to demand rather than simply operating at maximum capacity continuously.
- Maintenance: Dirty filters and restricted airflow can affect performance and efficiency.
Correct sizing is particularly important. Both undersized and oversized systems can perform inefficiently, which is why heat-pump selection should consider much more than the floor area of the room alone.
What Is the Most Economical Temperature for a Heat Pump?
For most households, you don't need to turn your heat pump up to 25°C or 26°C to create a comfortable home.
A moderate temperature of around 18°C to 21°C is generally a sensible starting point for winter heating, depending on your household and personal comfort requirements.
Increasing the thermostat doesn't make the heat pump warm the room instantaneously. You're simply asking the system to achieve a higher final temperature.
If you come home to a cold house, setting the heat pump to 28°C won't necessarily warm the room faster than selecting a comfortable temperature such as 20°C or 21°C.
Instead, allow the system to work steadily towards your desired temperature.
Is It Cheaper to Leave a Heat Pump on All Day?
This is one of the most common heat-pump questions, and the answer depends on how you use your home.
If nobody is home for a substantial part of the day, maintaining a high indoor temperature continuously may use unnecessary electricity.
However, repeatedly allowing a home to become extremely cold and then asking the heat pump to rapidly bring it back to a comfortable temperature isn't necessarily the best strategy either.
Modern inverter heat pumps are designed to adjust their output once the desired temperature has been reached.
Rather than constantly switching between maximum output and completely off, they can reduce their workload and maintain a relatively stable room temperature.
Using timers and Wi-Fi controls can be particularly useful. You can schedule heating around when your household actually needs it rather than heating an empty home unnecessarily.
Does Turning a Heat Pump Up Higher Heat the Room Faster?
Generally, no.
Think of the thermostat as the destination, rather than an accelerator.
If the room is 12°C and you want it to be 20°C, setting the heat pump to 30°C doesn't mean it will necessarily reach 20°C faster.
Instead, the system will continue trying to heat the room beyond the temperature you actually wanted.
Once you're comfortable, you may then turn it down or switch it off, potentially wasting energy in the process.
Choose the temperature you actually want and allow the heat pump to do its job.
Does Heat Pump Size Affect Running Costs?
Absolutely.
Choosing the right capacity is one of the most important parts of achieving efficient heating.
An undersized heat pump may struggle to reach the desired temperature and operate at high output for extended periods.
But bigger isn't automatically better.
An oversized heat pump may reach the target temperature very quickly and cycle unnecessarily rather than operating steadily and efficiently.
That's why professional heat-pump sizing considers factors including:
room dimensions + ceiling height + insulation + glazing + orientation + local climate + how the room is used.
Bay of Plenty Heat Pumps also provides an online heat-pump calculator as an initial guide to the output required for straightforward rooms, followed by professional advice when selecting the final system.
Does Insulation Make a Heat Pump Cheaper to Run?
Yes.
Your heat pump is only one part of your home's heating system. The building itself determines how quickly that heat escapes.
Ceiling, wall and underfloor insulation can help retain warmth, while good-quality curtains and double glazing can further reduce heat loss.
The easier it is for your home to retain heat, the less work your heat pump needs to do to maintain a comfortable temperature.
This is particularly important in older Bay of Plenty homes that may have considerably different insulation and glazing standards from newer properties.
Should You Close Doors When Using a Heat Pump?
If you have a single high-wall heat pump designed primarily to heat one living area, closing doors to unused rooms can often help concentrate heating where it's required.
Trying to heat multiple bedrooms down a hallway from a single living-room heat pump may not provide satisfactory results.
If you want consistent temperatures across several rooms, it may be worth considering a multi-room or ducted heat-pump system rather than expecting one high-wall unit to heat the entire house.
How Can I Reduce My Heat Pump Electricity Consumption?
A few relatively simple habits can make a meaningful difference.
- Use a sensible temperature. Avoid excessively high winter settings or extremely low cooling settings in summer.
- Clean the filters. Restricted airflow can reduce performance.
- Keep doors and windows closed. Don't make your heat pump compete continuously with outdoor air.
- Use timers and Wi-Fi controls. Schedule heating and cooling around your lifestyle.
- Reduce heat loss. Insulation, curtains and glazing all contribute to the overall efficiency of your home.
- Have the heat pump serviced. Professional servicing can identify airflow restrictions, excessive dirt accumulation and other issues affecting performance.
- Make sure the system is correctly sized. If you're buying a new heat pump, getting this right from the beginning can have an impact on comfort and long-term running costs.
Bay of Plenty Heat Pumps recommends professional servicing to help restore airflow and day-to-day performance and identify smaller problems before they develop into more significant faults.
Are Mitsubishi Electric Heat Pumps Energy Efficient?
Modern Mitsubishi Electric heat pumps use inverter technology that allows the compressor to vary its output according to demand.
Instead of continually operating at full capacity, the system can reduce its output as the room approaches the desired temperature.
The appropriate Mitsubishi Electric system will depend on your home and how you intend to use it.
Options include high-wall heat pumps, floor consoles, ducted central heating and cooling, OmniCore multi-room systems and Lossnay fresh-air/heat-recovery ventilation solutions.
For this reason, the most efficient heat pump isn't necessarily a particular model. It's the system that's appropriately selected, sized and installed for your home.
Choosing an Efficient Heat Pump for Your Bay of Plenty Home
Running costs are important, but they shouldn't be considered in isolation when choosing a heat pump.
A cheap system that's incorrectly sized or poorly installed may ultimately provide worse comfort and efficiency than a properly designed system.
The best approach is to consider the complete picture:
your home + room size + insulation + glazing + lifestyle + required temperatures + heat-pump efficiency + installation quality.
Bay of Plenty Heat Pumps are Mitsubishi Electric certified installers based in Tauranga, providing heat-pump installation, servicing and advice throughout Tauranga and the wider Bay of Plenty.
Frequently Asked Questions About Heat Pump Running Costs
How much does a heat pump cost to run per hour in NZ?
There isn't one accurate figure that applies to every heat pump. Hourly cost depends on the electricity tariff, system capacity, efficiency, room conditions, outdoor temperature and how hard the compressor is working. An inverter heat pump also doesn't necessarily draw the same amount of electricity throughout the entire hour.
Is a heat pump cheaper to run than an electric heater?
Heat pumps are generally much more energy efficient than conventional resistance electric heaters because they transfer heat rather than generating all their heat directly from electricity. Actual savings depend on the appliances being compared and how they're used.
What temperature should I set my heat pump to in winter?
Around 18°C to 21°C is a sensible starting range for many households. Individual comfort requirements differ, but setting the thermostat excessively high can increase energy consumption without necessarily making the room heat up faster.
Is 24°C too high for a heat pump in winter?
A heat pump can certainly be set to 24°C, but maintaining a higher indoor temperature generally requires more energy than maintaining 20°C or 21°C. If you're comfortable at a lower setting, that will usually be the more economical choice.
Is it cheaper to leave a heat pump running overnight?
It depends on the home, outdoor temperature, insulation and required bedroom temperature. If heating isn't required overnight, reducing the temperature or using timers may save electricity. However, households that need consistent overnight warmth may benefit from maintaining a moderate temperature rather than using an excessively high setting.
Should I leave my heat pump on when I'm at work?
If your home will be empty for many hours, maintaining the same temperature you use while at home may be unnecessary. Timers or Wi-Fi controls can allow the system to operate around your schedule.
Why has my heat pump suddenly become expensive to run?
Possible causes include colder weather, dirty filters, restricted airflow, inappropriate settings, doors or windows being left open, changes to electricity prices or a heat pump that requires servicing. If performance has noticeably changed, having the system checked is sensible.
Does cleaning heat pump filters save electricity?
Clean filters help maintain proper airflow through the indoor unit. Heavily clogged filters can restrict airflow and reduce performance, so regular filter cleaning is an important part of maintaining efficient operation.
Is a bigger heat pump cheaper to run?
Not necessarily. A heat pump that's too large can be just as undesirable as one that's too small. Correct sizing allows the system to operate efficiently while maintaining a comfortable indoor temperature.
How often should a heat pump be serviced?
The appropriate servicing frequency depends on usage and environmental conditions. Filters should be cleaned regularly, while periodic professional servicing can help maintain airflow, cleanliness, performance and reliability.
What is the cheapest way to run a heat pump?
There isn't one setting that's cheapest for every household. In general, good results come from choosing a moderate temperature, heating only the areas that need it, keeping filters clean, reducing heat loss, using timers intelligently and ensuring the heat pump is correctly sized and maintained.
Are heat pumps still worth it with increasing electricity prices?
For many New Zealand homes, yes. Electricity price increases affect running costs, but heat pumps remain an efficient form of electric heating. The overall value also includes the ability to provide both winter heating and summer cooling from the same system.
Talk to Bay of Plenty Heat Pumps
If you're considering a new heat pump and want to understand which system will provide the right balance of comfort, efficiency and running costs, professional sizing and installation are important.
Bay of Plenty Heat Pumps are certified Mitsubishi Electric heat pump installers providing heat pump installation and servicing throughout Tauranga, Mount Maunganui, Papamoa and the wider Bay of Plenty.
Whether you need a high-wall heat pump for one room or a larger multi-room or ducted system, we can help you choose a Mitsubishi Electric solution suited to your home.