SPOTLIGHT: Doing the math on doing the laundry.

BIG PICTURE: While purchasing a water saving, energy efficient washing machine recently, I consulted the EnergyGuide labels mandated by governments in North America. In the showroom, these labels inform the consumer how much energy each model uses.

The one attached to our washer tells me if I do six loads of laundry per week (2-3 is normal in our household), I’ll use a grand total of $8 worth of electricity over the course of an entire year. If my water heater relied on electricity rather than natural gas, it says, the total cost would be $11 a year.

click to enlarge

Six loads of laundry per week equals 312 loads per year, which comes to 90 kWh of electricity. Each individual load, therefore, uses 0.288 kWh.

I’m one of those people who tapes graphics from my utility company to my washer. The purpose of these graphics is to urge me not to do laundry when it’s most convenient, but to arrange my domestic life around external factors. Off-peak electricity prices are lower, they advise. I should therefore save money and behave responsibly toward the planet by doing my laundry only at certain times.

Until now, I’ve swallowed these arguments hook, line, and sinker. On the rare occasions in which I’ve ‘cheated,’ I’ve deliberately and consciously decided that diverging from the off-peak schedule was worth paying a few extra bucks.

After my new machine was delivered, however, I got out a calculator. And now feel like an idiot.

Where I reside, electricity costs 13.2 cents per kWh during the most expensive time of day, and 6.5 cents during the cheapest. The math looks like this:

1 load of laundry at the most expensive time of day costs less than 4 cents 

.288 kWh x 13.2 cents = 0.038 dollars  

1 load of laundry at the cheapest time of day costs less than 2 cents

.288 kWh x 6.5 cents = 0.019 dollars

This is a trivial difference. Of all the things that warrant my attention during a typical week, the timing of my laundry isn’t one of them.

In fairness, a few caveats are in order. Newer washing machines are 70% more energy efficient than older ones. The upcharge could therefore have been as high as 7 cents before I upgraded.

I have a natural gas-powered clothes dryer, and gas costs the same regardless of when I use it. But most people have electric dryers. According to this how-to-save-energy discussion, drying a load of laundry for 45 minutes uses 3.3 kWh of electricity – roughly 10 times the amount required by the washer. In my jurisdiction, the difference in cost between high-peak drying and low-peak drying is 23 cents (44 cents versus 21).

The implications of these numbers are obviously different for large families, but the typical Canadian household looks closer to my two-person situation. And it turns out, I’ve been wholly innumerate about these matters for decades.

When activists, energy companies, and government bodies told me there were significant cost savings to doing my laundry at certain times of the day, I believed them. But that isn’t the case. Washing a load at top tier prices costs 2 to 7 cents extra. Drying a load costs 23 cents extra.

How often have we been urged not to sweat carbon taxes and other green-inspired fees? The cost is mere pennies a day, say the activists. Well, that reasoning also works in reverse.

TOP TAKEAWAY: With a high-efficiency washing machine, it costs two cents extra to wash laundry whenever I please. That’s a premium I’m prepared to pay.

LINKS:

• my previous post: Laundry Blues and Greens: Part 1

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