Will Anderson: The Green House

Washing machines have become slicker and quieter. So guess what? we use them more

Here's a curious thing. In the olden days when washing machines consumed energy and water like hyperactive Alsatians, they always had three pipes sticking out the back: one for the drain and two for the hot and cold water. After a decade of energy labels and consumer pressure, the electrical shops are now full of poodles with oh-so-meagre appetites, yet these efficient models have only two pipes out the back - the drain and the cold fill. So instead of taking water from your hot tank or combi boiler, the modern washing machine draws cold water and uses electricity to heat it up. If you heat your water with a climate-friendly solar panel or wood-burner, this switch to dirty electricity seems particularly galling.

Surely some mistake, right? Well, no. You see, Alsatians and poodles are different beasts in every way. Sometimes when you design with energy in mind, you reach a threshold that changes your whole approach. Let me explain.

A new, efficient washing machine will use much less water than an old model - around 40 litres - and will often heat this water to no more than 40C, thanks in part to biological detergents which work best at this temperature. This hot water, however, is only required for the very first part of the cycle because all the rinses are cold. So our total hot water demand is down to about 10l. But in practice, only half of thiswill come from the hot pipe (if there is one), because both hot and cold water are drawn for a 40C or 60C wash.

This takes us over the threshold. When I spoke to technicians at AEG-Electrolux ( www.aeg-electrolux.co.uk) and Bosch ( www.bosch.co.uk) - brands with cold-fill only machines - they both drew my attention to the same issue. If you are drawing very little water from your hot water tank, a lot of the water will actually be taken from the pipe between your tank and the machine. Consequently, the machine has to "reheat" this water because it will have lost its heat while standing in the pipe. What's more, when the fill has finished you will leave another pipeful of hot water behind. Heating the water once in the machine, at the point of use, is therefore more energy efficient.

This ostensibly energy-saving redesign is based on the assumption that our houses are poorly designed for energy, in particular that our hot water store or supply is often far from where we actually use hot water. It is certainly a reminder of the importance of keeping pipe runs short, narrow and insulated wherever possible. If you have short pipe runs, or use solar hot water, or insist on washing at high temperatures, you may still do better with a cold- and hot-fill washing machine.

The improvements in energy and water efficiency of washing machines over the last 20 years have been remarkable. However, they have also become slicker, quieter and more pleasant to use. So guess what? We use them more - on average 270 times a year. This is the bind that constrains the benefits of energy-efficient design: we do not curtail our energy use if we do things more often as well as more efficiently.

When you do use the machine, make the most of it, because a half load uses much more than half the water and energy of a full load. In fact, Japanese use cold water for all their washing, so perhaps our behavioural shift from the boil wash to 40C should be seen as nothing more than a stepping stone to a future that is cold, bright and carbon-free.

* GREAT BUY

Keep your clothes out of the wash for longer with Green People "No Scent" Deodorant. £6.45 (08703 313 333, www.naturalcollection.com).

* GREAT WEBSITE

For more information about washing machines see www.washerhelp.co.uk. It makes a good case for prioritising durability over energy rating.

w.anderson@independent.co.uk

Discover more property articles at Homes and Property
PROMOTED VIDEO
Arts and Entertainment
TV The follow-up documentary that has got locals worried
Arts and Entertainment
Eminem's daughter Hailie has graduated from high school
music
Arts and Entertainment
Original Netflix series such as Orange Is The New Black are to benefit from a 'substantial' increase in investment
TVHoax announcement had caused outrage
Life and Style
Swimsuit, £245, by Agent Provocateur
fashion

Diving in at the deep end is no excuse for shirking the style stakes

News
One Direction star Harry Styles who says he has no plans to follow his pal Cara Delevingne down the catwalk.
peopleManagement confirms rumours singer is going it alone are false
Property search
Have you tried new the Independent Digital Edition apps?
Independent Dating
and  

By clicking 'Search' you
are agreeing to our
Terms of Use.

iJobs Job Widget
iJobs General

Dynamics CRM Developer (C#, .NET, Dynamics CRM 2011/2013)

£40000 - £60000 per annum + Benefits + Bonus: Harrington Starr: Dynamics CRM D...

Web Developer (C#, ASP.NET, AJAX, JavaScript, MVC, HTML)

£40000 - £45000 per annum + Benefits + Bonus: Harrington Starr: Web Developer ...

C# R&D .NET Developer-Algorithms, WCF, WPF, Agile, ASP.NET,MVC

£50000 - £67000 per annum + Benefits + Bonus: Harrington Starr: C# R&D .NE...

C# Developer (Web, HTML5, CSS3, ASP.NET, JS, Visual Studios)

£40000 - £50000 per annum + Benefits + Bonus: Harrington Starr: C# Developer (...

Day In a Page

Super Mario crushes the Messi dream as Germany win the 2014 World Cup in Brazil

Super Mario crushes the Messi dream

Germany win the 2014 World Cup in Brazil
Saharan remains may be evidence of the first race war, 13,000 years ago

The first race war, 13,000 years ago?

Saharan remains may be evidence of oldest large-scale armed conflict
Scientists find early warning system for Alzheimer’s

Scientists find early warning system for Alzheimer’s

Researchers hope eye tests can spot ‘biomarkers’ of the disease
Sex, controversy and schoolgirl schtick

Meet Japan's AKB48

Pop, sex and schoolgirl schtick make for controversial success
Iraq crisis: How Saudi Arabia helped Isis take over the north of the country

How Saudi Arabia helped Isis take over northern Iraq

A speech by an ex-MI6 boss hints at a plan going back over a decade. In some areas, being Shia is akin to being a Jew in Nazi Germany, says Patrick Cockburn
The evolution of Andy Serkis: First Gollum, then King Kong - now the actor is swinging through the trees in Dawn of the Planet of the Apes

The evolution of Andy Serkis

First Gollum, then King Kong - now the actor is swinging through the trees in Dawn of the Planet of the Apes
You thought 'Benefits Street' was controversial: Follow-up documentary 'Immigrant Street' has got locals worried

You thought 'Benefits Street' was controversial...

Follow-up documentary 'Immigrant Street' has got locals worried
Refugee children from Central America let down by Washington's high ideals

Refugee children let down by Washington's high ideals

Democrats and Republicans refuse to set aside their differences to cope with the influx of desperate Central Americas, says Rupert Cornwell
Children's books are too white, says Laureate

Children's books are too white, says Laureate

Malorie Blackman appeals for a better ethnic mix of authors and characters and the illustrator Quentin Blake comes to the rescue
Blackest is the new black: Scientists have developed a material so dark that you can't see it...

Blackest is the new black

Scientists have developed a material so dark that you can't see it...
Matthew Barzun: America's diplomatic dude

Matthew Barzun: America's diplomatic dude

The US Ambassador to London holds 'jeans and beer' gigs at his official residence – it's all part of the job, he tells Chris Green
Meet the Quantified Selfers: From heart rates to happiness, there is little this fast-growing, self-tracking community won't monitor

Meet the 'Quantified Selfers'

From heart rates to happiness, there is little this fast-growing, self-tracking community won't monitor
Madani Younis: Five-star reviews are just the opening act for British theatre's first non-white artistic director

Five-star reviews are just the opening act for British theatre's first non-white artistic director

Madani Younis wants the neighbourhood to follow his work as closely as his audiences do
Mrs Brown and her boys: are they having a laugh?

Mrs Brown and her boys: are they having a laugh?

When it comes to national stereotyping, the Irish – among others – know it can pay to play up to outsiders' expectations, says DJ Taylor