8 SEP 2025

What is ‘eco’ mode and how does it work?

We live in a world where our technology can work smarter, not harder. Even our washing machines and dishwashers can contain sensors that automatically choose the right setting, or functions that can start a cycle with the click of a remote control. However, one setting that most modern appliances have is an ‘eco’ mode.

But what does this ‘eco’ mode really do? Does it actually save energy, and is it better for the environment?

Let’s dig in and find out if ‘eco’ modes are indeed better for the environment and your energy bills.

Laundry child playing with washing machine | CB | 1200x580

What is ‘eco’ mode?

You’ve probably seen it before: ‘eco’ or ‘economy’, ‘water saving’, ‘energy saving’. Whatever the label, its aim is for your appliances to use less power and water while still getting the job done.

So how does it work?

The manufacturers set these functions to have different configurations of water temperature, water levels, and cycle times. So yes, eco modes might take longer, but that’s because they use colder water, and in some cases, less of it*. They’re working smarter, not harder.

Tip: Don’t forget to use your timer settings to further save on energy by setting it to turn off while you are out.

_{* ‘Eco mode’ can vary between models and brands. If you’re curious about what it means for your appliance, check your manual (it’s probably in your junk drawer).}

If it’s supposed to be ‘eco’ friendly, why is the cycle longer? Does a longer wash cycle mean that it uses more energy?

Eco mode is all about taking its time, using lower temperatures (since heating the water takes up most of the energy) and letting the detergent work its magic, rather than tackling it with heat and the force of the water.

Should you always use it?

Short answer: not always.

Eco mode is great for everyday washes. However, if you’re dealing with heavy-duty stains or a packed dishwasher, you might need to bite the bullet and put the occasional hot wash on.

The table below shows an example of the different modes of a household's dishwasher and washing machine.

Dishwasher

Cycles	Degree of soil + Type of load	Typical program phases	Duration (minutes)	Energy (kWh – kilowatt-hour)	Water (Litres)
Eco	Normal soil Mostly crockery and cutlery	Prewash Wash Rinse Dry	227	1.039	11
Heavy Duty Wash	Heavy Soil Crockery, cutlery, pots and pans	Prewash Wash Rinse Dry	155-170	1.5-1.7	14-15
Normal Wash	Normal Soil Crockery and cutlery	Prewash Wash Rinse Dry	130-140	1.4-1.6	15-17
Quick Wash	Fresh soil Crockery and cutlery	Wash Rinse	30	0.8	10
Rinse	All	Prewash	14	0.1	5

Washing machine

Cycles	Capacity	Program time	Energy consumption (kWh/cycle)	Water consumption (L/cycle)	Maximum temperature (°C)
Eco	9	3 hrs 45 mins	0.809	71	31
Eco	4.5	3 hrs	0.509	46	27
Eco	2.5	2 hrs 30 mins	0.126	36	21
Cotton 20°C	9	3 hrs 15 mins	0.357	117	20
Cotton 60°C	9	2 hrs 30 mins	1.504	134	60
Synthetics 40°C	4	2 hrs 30 mins	0.680	68	40
Quick Wash Cold	2	15 mins	0.015	43	15

_{Source: Is Eco Mode Your Best Bet on Your Electric Appliances?}

What else can help me save energy?

Energy companies like Contact Energy offer time-of-use plans such as our Good Nights Plan (free electricity from 9pm to midnight on weekdays^). The more you shift your energy usage to the free or discounted hours instead of peak hours, the more you can save. Plus, the power used during these times is more likely to come from renewable sources - another bonus for your carbon footprint!
_{^ The free period is for electricity usage and excludes gas charges. This plan is for customers with an eligible smart meter. T&Cs and Fair Use policy applies.}
For heat pumps, eco mode usually uses less energy than other modes because it runs at a lower fan speed and temperature to provide the same desired heat. Cranking up the heat pump to 30° might not heat your house faster, but it will use a whole lot of power. We recommend setting it at 18-21° to keep energy usage low.
Research suggests New Zealand could cut power use by 10% just by switching appliances off at the wall instead of leaving them on standby. That’s about $100 per year for a household!
Fun fact: Over 40% of microwaves in NZ used more electricity over a year keeping the clock and keyboard lit than they did heating food.
Talking about energy use with kids can make them more aware and help them start building energy-saving habits early. The sooner we understand how we use energy, the easier it is to make smarter choices.

Tweaking how you use your appliances can make a real difference—not just for your power bill, but for saving water and energy too. Small changes, big impact.