A key quality of life indicator

First, what is so important about washing machines? Hans Rosling explains:

What was the greatest invention of the industrial revolution? Hans Rosling makes the case for the washing machine. With newly designed graphics from Gapminder, Rosling shows us the magic that pops up when economic growth and electricity turn a boring wash day into an intellectual day of reading.

Fair enough. Washing machine access for everyone!  And by “everyone” we mean the expected world population of ten billion people.  Now, what are all those washing machines going to cost us in energy and carbon?  I did some calculations in the sidebar, but that can’t be right. 15 TWh per day?  How many power plants would that require?  How many wind turbines running at full capacity?

Yes, that’s about right

Thanks David MacKay, author of Sustainable Energy: Without the Hot Air.

@Footprint2Wings @HansRosling that would be 1.5 kWh/d/person. yes a reasonable estimate for the developed world.

— David MacKay FRS (@davidjcmackay) September 17, 2014

Peak Dryer

While the washing machine is critical, a drying machine isn’t as essential to quality of life. Clothesline technology doesn’t take that much time, and the fluttering cavalcade of drying clothes can be a charming part of life when you think about it. Line drying is a great application of passive solar and wind energy. There is, however, some cultural resistance to drying clothes on the line, as Stephen Colbert reports:

Americans, if you feel as strongly about the right to dry as you do about the right to bear arms, join the Right to Dry movement at Project Laundry List. On twitter @ProjectLaundry

Notes & Related:

Peak Washing Machine Calculations

How many washing machines would there be per capita? The rate in dense urban areas is lower than suburban areas, as people in cities are more likely to use a laundromat.  Is there an appliance corporation out there whose mission it is to supply peak washing machine? They should know how many washing machines that would be.  Remember, we’re expecting a world population to stabilize at around ten billion people.  10,000,000,000. 

How much energy does that use? Let’s start with how much energy it takes to wash and dry.  Assuming that the UK is at Peak Washing Machine, we’ll go with the numbers for an average UK citizen. Per David MacKay’s Without Hot Air, washing machines use 1kWh/day per person. Drying varies from 2kWh/d for a tumble dryer to 0kWh for line drying.  Let’s say on average, drying takes 0.5 kWh/day per person.

That’s 1.5kWh/day for washing and drying, times 10 billion people=15 Billion kWh/day, which is 15 Terrawatt hours per day, or 5,475 TWh per Year! 

Of course, we’d also have to calculate the energy required to manufacture and deliver the washing machines. 

How to reduce the carbon footprint of Peak Washing Machine:   Since the washing machine is a key factor in quality of life, unless you’re willing to give it up yourself, you can’t expect others to. That means we’ve got all these washing machines to run.  How do we take the footprint to zero?  There are several steps.

1.  Keep improving washing machine efficiency.
2.  Power the washing machines with clean, CO2 free energy like solar, wind, nuclear.
3.  Build the washing machines to last & be easily repaired. No built in obsolescence.
4.  Lower your standards and let the clothes get a bit fragrant before washing.
5.  As much as possible, dry with wind/solar energy - on the line.

To encourage drying with direct solar and wind energy support the Right to Dry!