What household appliances use the most power?

Posted on Aug. 18, 2023, 4:15 p.m.

What household appliances use the most power?

Which of your household appliances use the most electricity?

The cost of living is going up, with grocery costs, utility bills, mortgage repayments all on the rise. It’s now more important than ever to make sure we’re managing our utility costs down where we can.

In this article, we provide some advice from an electricity provider’s perspective on which of your appliances will typically draw the most power.

How much power does space heating use?

The first and most obvious source of energy use is your space heating (eg heat pumps, plug in heaters etc.).

Heaters are by far the biggest consumers of power in a home or business. They typically make up to 34% of a household’s total energy consumption.

Based on the new Healthy Homes standards, heat pumps generally require a power output that typically ranges between 2kW to more than 6kW depending on the insulation installed, and the space within your home. In contrast, a typical plug-in heater will have a power output of around 2kW to 2.5kW.

For example, if you run a heat pump with 2kW output for about 5 hours a day (3 days a week), at a power cost of around $0.25 per kWh, this comes out to be $32 per month (or $1 per day). Conversely, if you run two plug-in heaters to heat the same space with a power output of around 2kW each, running for around the same amount of time, this comes out to around $65 per month (or $2 per day).

One of the key differences in the example above is that a heat pump will be able to warm up a larger space (eg living room, hallway, kitchen) more cost efficiently when compared to your average typical plug-in heater.

How much power does hot water use?

The water in your home is typically heated by either a gas-powered or electric water heater. On your average monthly power bill, we find that this is usually the next largest source of power in your home.

If your water heater is electric, you would typically use about 3kW of electricity per hour depending on the capacity output of your heater. For most households, we find that they run the water heater for about 2-3 hours per day.

This means that the cost of running hot water in your home (on an electric water heater) is about $45 to $70 per month (or $1.5 to $2.5 per day) if used a couple of hours each day.

For some properties, particularly those on the Counties Network, their hot water heaters are on controllable load. This means that your network operator can switch off the water heater for your home at peak demand periods to manage the overall load on their network.

This doesn’t necessarily mean that you don’t have access to hot water - only that the heating component stops running to prepare any new hot water. Your water cylinder will still contain plenty of hot water, which will generally stay hot for hours. Unless you use all of the water in your cylinder in one go (which is unlikely), you’d typically not experience any real difference in access to hot water for your home.

How much power does your fridge use?

As you would expect, cooling appliances and refrigeration use a lot of power. This is largely because it runs continuously throughout the day, but with some cycling that helps it to conserve power.

For a typical family of four (2 adults, 2 children), we’d expect a 400L fridge to be large enough for what they need. All fridges cycle on and off for about 12 cycles a day to manage the power it draws. For your typical fridge, this means it could cost you about $15 to $20 per month to keep your groceries cool and fresh.

However, this varies significantly depending on the energy rating of the fridge. With new technologies, you can find even greater savings on your power bill, but can sometimes come with a much higher price tag. Depending on your budget and how much you’re willing to spend, it is worthwhile shopping around for a fridge that meets you and your family’s needs.

How much power does the washing machine use?

On average, a washing machine consumes about 12% of the energy on your monthly bill.

The largest component that uses the most power is the heating of the water within the washing machine. On average, the washing machine will cost you about $2 to $3 per load. If you wash 2-3 loads of washing per week, this equates to around $120 to $220 per month (or $4 to $7 per day).


As you can see from the above, the main appliances that are used in the average kiwi household can vary by quite a bit. It's important to pick the right appliances that suits you and your family which meets your needs. By putting in the work to research the options available to you within your budget, you can help keep your power costs manageable, and not stretch your wallet too thin.

Our goal is to build a better energy world by creating an Open Energy Network. This means we're constantly exploring new and better ways to help kiwis live better.

At Tensor, we provide households (and businesses) with flexible options that can be catered to what they’re looking for. By identifying your needs first, we’re able to help you find the best pricing structure, plan and deal suitable for your property. Come join us in our journey.

If you’re considering switching power suppliers to help manage your utility bills and/or would like to discuss your options for power supply, contact us using our website chat, our general email address info@tensor.co.nz, or using our contact form here to talk through your options.