Managing Energy Costs on Washing & Drying At Night

The washing machine and the clothes dryer are two of the most moveable appliances in the house. The washing doesn't mind what time it gets done, and most modern machines can be set to start later.

This guide is about those two machines, plus the dehumidifier that often runs alongside them: what each one costs to run, why moving them into off-peak hours makes sense on a time of use plan, and how to set them up so it happens without you thinking about it. For everything else in the laundry, including cold washes, spin cycles and line drying, see our Take Charge laundry guide.

Night Saver offers lower rates from 9pm to 7am compared to day rates on the same plan. Any savings depend on your usage and how much of it you shift into those hours. Ts&Cs and eligibility criteria apply.

Three machines, three different patterns

Washing machines run most days in most Kiwi homes, and how much energy they use comes down largely to water temperature. According to EECA, a hot wash can use almost 10 times more electricity than a cold one, because most of the energy goes into heating the water.

Dryers are a different story. They create heat and move air for an hour or more, which makes them one of the more power-hungry appliances in the house. Dehumidifiers draw less at any one moment, but they often run for hours at a time, especially in winter when washing gets dried inside.

Measuring in kilowatt hours

Power prices change, but the energy an appliance uses per load stays fairly steady. That's why the table below leads with kilowatt hours (kWh), with costs shown at today's national average as a guide.

These figures are indicative estimates, not a bill guarantee. Costs use the national average residential price of 42.1c per kWh from MBIE's Quarterly Survey of Domestic Electricity Prices (15 August 2026), rounded to 42c. Your own rate will depend on your plan, network and region, and actual energy use varies by model, settings and how you use it.

A household doing a warm wash and a vented dryer load every day is using more than 1,500 kWh a year on laundry alone. At 42c per kWh, that's around $640.

It's a flexible job

Unlike cooking dinner or warming up the lounge, laundry rarely has to happen at a set time. EECA lists washing machines, dryers and dishwashers among the appliances households can run in off-peak hours.

It uses a lot of energy in one go

Moving a 3 kWh dryer load makes far more difference than moving a phone charger. The bigger and more regular the load, the more a lower rate is worth.

Most of us do it in the evening peak

Plenty of households put a load on after dinner, right in the middle of the 5pm to 9pm evening peak. Waiting until after 9pm, or setting a delayed start, moves that load into Night Saver's lower-rate hours without changing much else about your evening.

Because rates differ between plans and regions, the most useful number is the gap between your day rate and your night rate. Your bill or plan details will show both. The table below shows what every 10c per kWh of difference is worth over a year. If your gap is 15c, multiply by one and a half. If it's 20c, double it.

These are straight calculations rather than a promise of savings. What you'll see depends on your rates and how consistently the loads move.

Finding a routine that fits

There's no single right way to do this. Here's how off-peak laundry can look for a few different households.

If you work standard hours

• Load the washing machine before bed and use delayed start so it finishes around the time you get up.

• Hang it out before you leave, or pop it on an airer.

• Save the dryer for wet weeks, and run it after 9pm while you're still up.

If you're a night owl

You're already awake in the lower-rate window. After 9pm is a natural time to run a load, move it to the dryer or airer, and still be up when it finishes.

If you're an early riser

A load started at 5am is usually done well before 7am. Many machines have an end-time setting, so you can load it the night before and have it finish as you're making the first coffee.

If you work shifts

Your routine may already line up with the lower-rate hours. A wash started while you get ready for a late shift, or when you get home in the early hours, can land in the window without any extra planning.

If you have a busy family home

With young kids, the washing sometimes just needs doing when it needs doing. Aim for the biggest loads, like sheets and towels, to go on after 9pm a couple of times a week, and let the rest happen when it happens.

If you're home during the day

Sunny days are ideal for the washing line, which uses no electricity at all. If most of your household's power use happens during the day and can't move, a time of use plan may not be the best fit, and that's worth weighing up before you switch.

Getting delayed start working for you

1. Check your manual for a "delay start" or "end time" function. Some count the hours until the cycle begins, others let you pick when it finishes.

2. Find out how long your usual cycle takes. If it's 90 minutes and you want it done by 6.30am, it needs to start by 5am.

3. Set the delay so the whole cycle sits between 9pm and 7am.

4. Load the detergent, close the door and press start before bed.

5. Unload soon after it finishes so the washing doesn't sit damp.

Older machines without a timer

A smart plug can switch power on at a set time, and EECA notes these can help households make the most of off-peak power. They only work with washing machines that start or resume when power returns, and many modern machines don't, so check your manual first. Use a quality plug rated for the appliance's full load. We wouldn't recommend using a smart plug to start a clothes dryer.

Moving laundry into the evening and early morning makes sense, but a few habits matter more when appliances run at quieter times. Fire and Emergency New Zealand recommends:

• Cleaning the dryer's lint filter before every use

• Not overloading the dryer

• Leaving space around the dryer so it can vent properly

• Letting the full cycle run, including the cool down, before opening the door

• Considering a heat alarm in the laundry, as a smoke alarm there may give false alarms

We'd also suggest only running a clothes dryer when someone is home and awake. The stretch between 9pm and bedtime, or first thing before 7am, works well for this.

Dehumidifiers

Dehumidifiers are built to run for long periods, and many switch off automatically when the tank is full. Keep the air vents clear, follow the manufacturer's instructions, and use the built-in timer if it has one to keep running time inside the lower-rate hours.

Drying inside

Drying washing inside adds moisture to the air, which makes a room harder to heat. If you use an indoor airer, a small room with the door closed and a dehumidifier on a timer is usually more efficient than drying in the lounge. Our laundry guide covers drying habits in more detail.

Most Kiwi households will use a mix of peak and off-peak power for their laundry, and that's okay. The school uniform that needs washing tonight will get washed tonight.

What makes the difference is a routine where the bigger, more flexible loads land in the lower-rate hours most of the time. A couple of changes, repeated week after week, add up to money that can go towards other things for the household.

Key points to remember

• Cold washes use a fraction of the energy of warm washes.
• The dryer is usually the biggest laundry load to move.
• Delayed start and end-time settings do most of the work for you.
• Run the dryer when someone's home and awake.
• A mix of peak and off-peak laundry is normal.

Night Saver offers lower rates from 9pm to 7am every night, compared to day rates on the plan. It's an open-term plan and needs a communicating smart meter. It tends to suit households that can move energy-heavy tasks like laundry or dishes to after 9pm. If most of your power use happens during the day, another plan may suit you better, and you can compare our plans side by side.

Other useful resources

• Take Charge - Saving Power In The Laundry

• EECA: Easy ways to save on your energy bills

• Electricity Authority: time of use plans

• Fire and Emergency NZ: Dryers and electric blankets

• Consumer NZ: How much power do your appliances use?

This guide is general information only. It isn't electrical, plumbing, fire safety, food safety or financial advice, and nothing in it should be relied on as a guarantee of safety or of any particular saving.

Always follow the manufacturer's instructions and safety warnings for your appliances and devices, and use a registered electrician or licensed plumber for any electrical or plumbing work. If you're unsure whether something is safe to run while you're asleep or away from home, don't.

Energy use and cost figures are indicative estimates based on typical appliances and the national average residential price of 42.1c per kWh (MBIE Quarterly Survey of Domestic Electricity Prices, 15 August 2026). Your actual costs, and any savings, will depend on your plan, rates, network, meter, appliances and how you use them.

Night Saver offers lower rates from 9pm to 7am compared to day rates on the same plan. Anticipated savings are based on those lower rates, and actual savings vary based on usage. Night Saver requires a communicating smart meter. Ts&Cs and eligibility criteria apply to all Meridian plans and offers.

To the extent permitted by law, Meridian Energy isn't liable for any loss, damage or injury arising from reliance on the information in this guide.

Sources

• EECA, Heat water efficiently: hot washes can use almost 10 times more electricity than cold washes. https://www.eeca.govt.nz/for-homes/energy-saving-technology/water-heating/heat-water-efficiently/ 

• EECA, Easy ways to save on your energy bills: washers, dryers and dishwashers can be used off-peak; smart plugs can help with off-peak use. https://www.eeca.govt.nz/for-homes/save-on-your-energy-bills/easy-ways-to-save-on-your-energy-bills/ 

• Electricity Authority, How to get cheaper power bills with a time-of-use plan: typical peak hours and using delay start. https://www.ea.govt.nz/your-power/ways-to-save-energy/how-to-get-cheaper-power-bills-with-a-time-of-use-plan/ 

• Fire and Emergency New Zealand, Dryers and electric blankets: dryer safety checklist. https://www.fireandemergency.nz/home-fire-safety/home-fire-hazards/dryers-and-electric-blankets/ 

• MBIE, Quarterly Survey of Domestic Electricity Prices, 15 August 2026: national average 42.1c/kWh. https://www.mbie.govt.nz/building-and-energy/energy-and-natural-resources/energy-statistics-and-modelling/energy-statistics/energy-prices/electricity-cost-and-price-monitoring 

• Meridian Energy, Night Saver plan. https://www.meridianenergy.co.nz/for-home/pricing-rates/night-saver-plan 

• Appliance draw and run-time assumptions are consistent with Meridian's Take Charge laundry guide. https://www.meridianenergy.co.nz/good-energy/energy-efficiency/take-charge-saving-power-in-the-laundry