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Episode 12

Why Does the Eco Wash Programme Take 3 Hours?

Eco washes run for hours because heating water uses most of the electricity and time doesn't. The energy label rewards it, up to 4 hours in the EU.

5 November 20267 min readVideo 8:11

The eco programme takes around 3 hours because most of a washing machine's electricity goes into heating water, so eco heats the water less and makes up for it with time. The energy label is measured on that one programme, so makers stretch it as long as the rules allow: in the EU up to 4 hours, and in Australia with no limit at all.

Watch the episode: The 25-Hour Washing Machine 8:11

Chapters

The 25-hour washing machine

In 2026 the Australian consumer group CHOICE gave Hisense a Shonky Award "for gaming a broken system". The product, the Series 8i Heat Pump Washer Dryer Combo, earned its 5-star washing rating on a 728-minute programme, more than 12 hours. Its Eco drying setting took 811 minutes (13.5 hours) to dry a full 8 kg load. Run both rating programmes back to back and one load takes over 25 hours.

It is marketed as "super energy-efficient", with 8 stars for drying, but only on Eco. The default drying programme took 8 h 45 min and left the laundry still very damp. The only acceptable result was a 3.5 kg load on the regular programme, in about 3 hours. Samsung got there earlier: in 2017 its washer-dryer won a Shonky for a cycle over 6.5 hours, its third year in a row.

Your machine is probably not that slow. Still, in CHOICE's tests the average front loader went from 99 minutes to 143 minutes in ten years, while top loaders barely moved, from 55 to 58. That is with a 3.5 kg load; one machine took 6 h 50 min at full capacity. On eco 40-60, the EU's standard eco programme, a wash takes three and a half hours or more. I wanted to know why the button meant to save something takes the longest.

Where does a washing machine's electricity go?

I had pictured the motor as the hungry part. It isn't. Most of the electricity goes into heating cold tap water, and turning the drum and pumping use little. Washing at 20 °C instead of 60 °C saves 70% of the electricity on a typical A+ machine.

The catch is that cooler water cleans less. In 1959 Herbert Sinner, head chemist of Henkel's detergent department, defined four factors behind a clean wash: mechanics, temperature, time and chemistry. They can stand in for each other. If one is reduced, another must grow, so a lower temperature can be offset by a longer programme. Newer low-temperature detergents help too, with more enzymes that work in cooler water.

FORUM WASCHEN gives an example: a short 60 °C programme uses 1.3 kWh, while eco 40-60 gets the same result with 0.5 kWh, about 60% less. Short programmes often use more energy and water to clean in less time. And eco water is barely warm. In one 8 kg Miele, the laundry reaches at most 43 °C at full load, 32 °C at half load and 25 °C at quarter load.

Why the label made programmes longer

The energy label is declared on one efficient test programme. EU researchers found manufacturers learned that longer programmes beat higher temperatures as a way to wash well on little energy, which earned a better label class. Short programmes usually need higher temperatures and more energy.

By 2016, 75% of washing machines declared A+++ on the old label. In a decade, programme duration doubled for small machines and doubled or tripled for large ones, up to 6 hours for a full load. Those test programmes often ran beyond 4 hours, and until 2021 duration was not part of any EU requirement or shown on the label.

Europe's 4-hour limit, and everyone else's

On 1 March 2021 the EU rescaled the label to A to G, and its review aimed to respond to what consumers expected about programme duration. Every washing machine now needs a programme called eco 40-60, for normally soiled cotton washable at 40 °C or 60 °C, together. It must be the default where a machine selects automatically, no other programme may have "eco" in its name, and a quick programme is not even mandatory.

It is also the programme the EU's efficiency, duration and water rules apply to, with a time cap that depends on the drum's rated capacity. At full load: 137 minutes plus 10.2 minutes per kg, never more than 240 minutes. For an 8 kg machine that works out at about 3 hours 39 minutes. The 8 kg Miele above takes 3 h 39 min at full load. The label now shows that duration in hours and minutes, and manuals must say the most efficient programmes are generally lower temperature and longer.

Other countries went other ways:

Country	What happened
United States	After a March 2018 petition from the Competitive Enterprise Institute over slow dishwashers, DOE created short-cycle classes in 2020 (dishwashers 60 minutes or less, front loaders under 45). They were revoked from 18 February 2022.
United States	The 2022 test procedure added a way to measure cycle time, which the old one lacked.
Australia	The manufacturer nominates the test programme, and star ratings set no requirement for cycle time.

That is how Hisense got its stars. Makers can test on their gentlest settings at the expense of cycle time, other brands nominate impractical programmes too, and Hisense went furthest. CHOICE's whitegoods expert says Hisense broke no rules. Australia's 2024 rules add the program time in minutes to the washer label, in force 12 months after 4 October 2024. Older labels without it may be seen until 3 October 2030.

Who actually presses eco?

A 3-hour programme has another problem: someone has to choose it. In a Miele survey of 1,000 Germans in 2023, only around 15% mainly used eco on the washing machine, and 41% of the less energy-minded thought eco was pointless on an A-rated machine. A German in-home study of 236 households found every fourth cycle was at 60 °C, and the machines tended to be underloaded.

A University of Bonn survey of over 5,000 people in 11 countries found consumers want to save energy but do not believe long cycles save it. Consumer groups found people avoid the most efficient programmes because they last too long, so for most loads the label's saving never happens.

Dishwashers have the same problem. Owners use eco for only about 20 to 30% of cycles, short programmes last about 30 minutes, and the best dishwasher in the EU benchmark takes 4 h 55 min on eco. Stamminger proposes a "short eco" programme that saves as much in much less time, with a stronger detergent. Meanwhile Miele says consistent eco use saves up to €335 over 10 years, which is the maker's own figure.

Check the label, or your manual

Heating water costs electricity, and time doesn't, so the label rewards patience. Next time you pass a washing machine in a shop, or open your own machine's manual, look for the programme time. In the EU the label shows how long eco 40-60 takes, and Australia's newer labels show it in minutes.

So how long does your eco programme take? And do you ever actually press it?

Sources

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