April 13, 2017 | Miles Durie

It's hot to be cool

Ventless heat-pump dryers dry clothes more efficiently at cooler temperatures

It may seem like the last place in your house you'd look for cutting-edge technology, but the laundry room is a pretty cool spot these days. No, seriously.

An exciting innovation that's reached our shores in recent years is the ventless heat-pump clothes dryer. They've been available since the 1990s in Europe, where the higher cost of electricity is a major incentive toward using less of it, but are just now developing a presence here.

What are they? Well, first let's look at how a conventional dryer works.

The familiar electric vented dryer consumes about 4,000 to 5,000 watts on average during a drying cycle – a lot more on startup and a lot less during cool-down. It uses an electric fan to take in air, pull it past a heating element and blow it through a rotating drum full of damp laundry and out through a vent to the great outdoors, carrying away water that has been vaporized by the hot (up to 60 C) airflow.

Around 20 to 25 per cent of the thermal energy cranked out by a conventional dryer's heating element goes straight out the vent hose. The hole in your wall for the vent is also a liability, since it allows an exchange of indoor and outdoor air, making your heating and cooling systems work just a little harder.

A heat pump dryer is ventless, so no hole is needed. It works by circulating warm air through your laundry, into the cold side of the heat pump where the water is condensed out and run down the drain, then back through the warm side of the heat pump and into the dryer again, and so on.

It's essentially a dehumidifier for your clothes, and it uses 30 to 60 per cent less electricity than its vented electric counterparts.

It's essentially a dehumidifier for your clothes, and it uses 30 to 60 per cent less electricity than its vented electric counterparts – most tests result in 50 per cent savings. User reports suggest the drying time is a bit longer, but that the much cooler temperatures inside the drum are great for your wardrobe, towels and sheets.

Whirlpool was the first on the Canadian market with a heat pump dryer, and other companies are starting to make inroads. In the U.S., there are at least 10 heat pump dryer models available from companies such as Kenmore, LG, Beko, Blomberg and Whirlpool. Elsewhere in the world they are produced and sold by Electrolux, Bosch, Miele, and Panasonic.

The downside is that these dryers cost significantly more than a vented unit. In fact, they can cost more than twice as much. You can recoup some of that investment in operating costs, less wear and tear on your clothes and a more airtight home, but it will take a while.

With all the advantages these units can offer, you'd think they'd be prime candidates for rebates under the province's climate change strategy. But the Energy Efficiency Alberta website currently doesn't list dryers at all, even though you'll be able to get a rebate when buying a more efficient washing machine.

Tagged: Digital Downlow | Dryers | energy efficiency alberta | Energy Saving Tips | Guest Column