How long will it take an energy-efficient washer/dryer to pay for itself?

The big cost in washing clothes is heating the water, so if you really want to save money, use less hot water

A Kenmore energy-efficient washer and dryer from sears. If you really want to save money on your energy bill doing laundry, turn down your water heater.

Handout/Sears, Roebuck and Co./Reuters/File

October 29, 2011

Saving Pennies or Dollars is a new semi-regular series on The Simple Dollar, inspired by a great discussion on The Simple Dollar’s Facebook page concerning frugal tactics that might not really save that much money. I’m going to take some of the scenarios described by the readers there and try to break down the numbers to see if the savings is really worth the time invested.

Aimee writes in: how many loads of laundry do i need to do to have an energy efficient pay for itself?

Obviously, this is going to vary quite a lot depending on the specific “normal” washing machine and the specific high-efficiency washing machine. I’ll go into the calculations using some aggregated statistics to show how many loads, on average, you’d have to do in a high-efficiency machine to make up for the extra cost.

CNet reports that you can buy a normal top-loading washing machine for $300-$650 and a high-efficiency machine for $600-$1,600. We’ll take the 40th percentile in both ranges, as it will more or less average the ones readers might actually buy and ignore the very high end ones with unnecessary bells and whistles.

This means we’ll be using a cost of $440 for the normal machine and $1,000 for the high-efficiency machine. That’s a difference of $560.

What about energy and water use? I used the energy calculator on the Mr. Electricity site and calculated that a top-loading (normal) washer would use $0.62 in energy and water per load, while a front-loading (high-efficiency) washer would use $0.41 in energy and water per load. I assumed that you’d be doing equal amounts of hot, warm, and cold washing and an electric water heater with a cost of $0.12 per kilowatt hour in obtaining those numbers.

That means, for each load of laundry done, a high-efficiency washer would save you $0.21 per load.

At a rate of $0.21 per load, you’d have to do 2,667 loads to make the high efficiency washer worthwhile.

That’s a lot of loads at first glance. However, the average American household does almost 400 loads per year, which means you’d be at that level in about six and a half years.

Of course, much of this calculation is dependent on the exact numbers used. Let’s say, for example, you’re comparing the lowest-end top loader with the lowest-end front loader, you’d have a difference of $300 instead of $560. That would only require you to do 1,428 loads to catch up. That’s about three and a half years.

Let’s say you’re living in an area with an energy cost of $0.15 per kilowatt hour. Your savings per load would jump to $0.22 per load, requiring you to have to do only 1,364 loads to catch up. You’re getting down to three years and a few months.

Here’s the real truth: the big cost in washing clothes is the cost of heating the water. If you want to start saving money on each of your laundry loads, the best way to start is to minimize your cost of heating your water. A simple step would be to turn down the heat level on your water heater. A more drastic (and expensive up front) step that would save money in the long run is to use a tankless water heater.

For me, it would come down to cash on hand. If I were buying on credit, I would get the least expensive washing machine I could, as the interest on credit card debt destroys any energy efficiency savings I might get. If I were paying cash and could afford either option, though, I’d get a reliable energy efficient one, sticking with recommendations from Consumer Reports.