Ventless and Vented Electric Clothes Dryers: An In-Depth Guide

Electric clothes dryers have been around for a really long time, so you would be excused for thinking that, except for the addition of electronics and “smart” features, not much about electric dryers has changed in decades.

But it turns out that consumers have a lot of new options, including ventless dryers that don’t need an outside exhaust, condensing dryers that use dehumidifiers to dry clothes, and energy efficient models that use heat pumps instead of electric resistance heating.

Some of these types of dryers have been popular in Europe for decades, but are new to the North American market. Unfortunately for consumers, the terminology can be confusing: for example, while all heat pump dryers are ventless, not every ventless dryer uses a heat pump.

According to the United States census, about 80% of home clothes dryers in American homes are powered by electricity, so they are far and away the most popular choice of homeowners.

Whether you’re looking to upgrade your existing electric dryer or you’re deciding whether it makes sense to switch from gas to electric, this article will help to explain all the choices available.

Why choose an electric clothes dryer?

When it comes to a clothes dryer, the common choice is between electric and natural gas. As an aside, if you want to reduce the amount of energy you use to dry your clothes, one of the best options is a good old fashioned clothesline. Not only will a clothesline dry your clothes using free solar and wind energy, but it is also the most gentle method of drying, making your clothes last longer. They will also smell great after drying in the fresh air.

But hanging clothes out to dry takes some time (I can attest to that; it was one of my chores as a kid). Also, not everyone is comfortable with having their underwear on display for the neighborhood to see. In fact, many homeowners associations ban the use of clotheslines.

This means that an electric clothes dryer is the next most environmentally friendly option if you don’t want to use natural gas. A properly installed gas-burning clothes dryer will vent its combustion byproducts outside, avoiding the sort of indoor air quality issues that are associated with a gas stove. However, a leak in the exhaust duct is possible, which would hazardous byproducts (like carbon monoxide) into a home. In this respect, electric dryers are a safer choice. Finally, if reducing your carbon footprint is also a goal you have, an electric clothes dryer will help to achieve that.

So, environmental impact is one reason why consumers might choose electric. Another is that the location in your home where you want a dryer installed might not have a gas hookup but does have an electric outlet. In fact, one detail that a lot of consumers might not be aware of is that some ventless heat pump clothes dryers have such low power requirements they only need a 120v power outlet, in contrast to the 240v outlet that conventional electric clothes dryers require. This can potentially mean more choices about where in your home you can install a dryer: you can simply plug these heat pump models into any standard power outlet.

Types of electric clothes dryers: ventless, condensing, heat pump, and conventional

If you go shopping for an electric clothes dryer, you’ll find that most models for sale are conventional vented. This means that they use an electric resistance coil to generate heat, and vent moisture and hot air to the outside of your home.

Alternative types that are ventless and may use heat pumps are growing in popularity but are still much less common. I just did a quick search on homedepot.com and found out of 222 electric models for sale 41 were ventless, while on lowes.com only 12 of out 143 electric dryers were ventless.

All conventional electric dryers are vented, while all condensing and heat pump models are ventless, which gives you a quick way to narrow your search if you’re considering one of these alternatives. The table below summarizes the types and key characteristics that differentiate them.

All about conventional vented electric dryers

Conventional electric clothes dryers work by taking indoor air and heating it with an electric resistance coil. The warm air extracts moisture from the clothes as they tumble in the drum, which is then vented outdoors through ductwork.

One of the main advantages of these dryers is low initial cost: you can find many 7 cubic foot capacity models starting around $500-600 in price range. More expensive models add “smart” features such as a greater choice of cycles, better drying sensors, or steam to reduce wrinkles, but the basic operation of using electric resistance to generate warm air that is eventually vented outside remains the same.

Compared to ventless models, vented electric dryers can generally dry clothes faster. Vented electric dryers require a 240 volt service line with a capacity between 20 amp and 50 amps. This means that the resistance coil in these dryers can usually generate higher temperatures than heat pump models, allowing clothes to dry faster.

A disadvantage of this type of clothes dryer is that they are less energy efficient. Compared to an electric resistance coil, a heat pump can generate 2-4 times as much heat using the same amount of electricity. Because the majority of electricity used by an electric clothes dryer is for heating, using a heat pump instead of electric resistance heating can drastically reduce its energy consumption.

Another - and more subtle - reason that vented clothes dryers are less efficient is that they take conditioned air from inside your home and blow it outside. If you live in a temperate climate this might not matter much, but it can be a significant energy loss any time the outside temperature differs widely from the indoors.

For example, let’s say that it’s a really cold winter night and the temperature outside is 0°F. If you turn on your vented electric clothes dryer, it will take nice, warm air that’s inside your house and blow it outside. To replace this warm air, cold outside air will be pulled into your home through air leaks around windows, doors, and other seams in your building. If your heating system has been working hard to keep your home at a comfortable 70°F, that’s a big temperature difference that will need to be made by your heating system.

Conventional electric clothes dryers have a relatively low initial cost, but because of their low efficiency, they can end up costing you more in the long run than ventless dryers.

How ventless dryers dry your clothes

Vented dryers remove moisture from clothes by taking heated moist air from the tumbler and exhausting it outside. Ventless dryers, in contrast, use either a condenser or a compressor to remove moisture from the air. With both types, the collected water is either piped into a nearby sink or drain pipe or collected into a container that must be emptied after every cycle.

Here’s how ventless dryers that use a condenser work. A condenser is a type of heat exchanger. A heat exchanger has two separate air paths that are separated by a metal surface. One path contains warm air while the other path is cool. When the warm air hits the colder surfaces of the condenser, the moisture in the air turns into liquid, in the same way that a relatively cold bathroom mirror fogs up when you take a hot shower.

In this type of condensing dryer, the warm air comes from inside the tumbler, while the cold air comes from a secondary path that uses room air. This means that the dryer takes room air, passes it through the condenser/heat exchanger, and vents the air (which is now a little warmer) back into the room. Because its constantly dumping warm air into the surrounding room, this type of dryer uses more energy to keep the air inside the tumbler warm. In fact, they can use more energy than a conventional electric dryer. In this type of condensing dryer, warm air is generated by an electric resistance coil.

A different type of ventless dryer also uses a condenser, but the condenser is instead used to recover heat for drying the clothes. Moisture from the air is removed by the compressor of a heat pump, which is also responsible for generating heat.

Other types of heat pumps, such as dehumidifiers and air conditioners, all generate water through condensation in this way. Here’s a diagram of a heat pump clothes dryer:

Differences between ventless condensing clothes dryers (a summary)

To recap, there are two types of ventless condensing clothes dryers: one uses an electric resistance coil to generate heat, while another uses a heat pump.

Both types include a condenser in the system, but for different purposes: in the former, the condenser dehumidifies the air, while the latter uses it to produce heat.

Because of this, both can be referred to as condensing dryers, even though one of the key features differs between them. Heat pump dryers can be 30-50% more energy efficient than other electric dryers, so if lower operating costs or reducing your environmental impact are important to you, you’ll want to look for this.

But if both types can be called condensing dryers, how do you differentiate between them when shopping?

Fortunately, if a condensing dryer contains a heat pump, the manufacturer will usually prominently mention this in the product description. If the product description doesn’t mention a heat pump, you can assume that it’s a condensing dryer that uses electric resistance heating.

Finally (and to add to the confusion) some clothes dryer are hybrid heat pump systems, which mean they use the heat pump to generate heat most of the time, but use an electric resistance coil whenever a higher temperature is required.

Ventless dryers eliminate the need for duct installation

There are some big advantages to choosing a ventless clothes dryer.

First of all, because they’re ventless, you don’t need to worry about installing ductwork from the appliance to the outdoors. Avoiding this installation expense might mean that it’s cheaper overall to go with a ventless, even though they are often roughly twice the price of a vented model.

Ventless models also don’t “steal” energy from your home by taking conditioned indoor air and blowing it outside, helping to make them even more energy efficient.

Finally, there are some heat pump models that only need a 120v power outlet. They are generally smaller models that may be less suitable for families that do a lot of laundry, but if you tend to do fewer or smaller loads, these compact versions can be installed in a home without the need to hire an electrician to run a 240v line for you. In fact, most people tend to purchase oversized dryers and could instead get buy with a smaller model.

Ventless models are usually slower

While ventless models have advantages over vented, but there’s one significant area where they often perform worse: drying performance.

Ventless models, whether they use a heat pump or electric resistance coil, are generally slower at drying than vented models - about 30% slower, according to data from energystar.gov. In spite of using longer run times to dry a load, ventless models on average are still more efficient.

On the plus side, slower drying is more gentle on your clothes, although you can achieve this with any dryer by selecting a lower temperature.

Ventless models will usually reduce your electricity costs

If energy efficiency is a criteria that’s important to you, the Energy Star website has a database of models that meet the ENERGY STAR certification, which will help you understand exactly how much energy one model uses versus another. Models with this certification meet a minimum standard measured as Combined Energy Factor (CEF), which describes how many pounds of damp clothes the appliance can dry per kilowatt-hour (kWh) of energy consumed, with higher numbers indicating better efficiency.

CEF is translated for gas dryers, so the CEF number listed for a gas dryer is the kWh-equivalent amount of energy contained in the natural gas it uses, making it possible to compare the energy usage of electric and gas dryers. (Your gas bill will typically list your gas usage as therms or CCF, not kWh.) CEF includes the total energy use by the dryer, which includes the electric motor to rotate the drum and any standby energy used by the electronics.

Energy Star certification also requires a minimum drying time of 80 minutes, based on a test cycle that uses a standard load of fabric with a measured water content. If you explore the models listed on the energystar.gov website, you’ll find that many vented electric models take around 60 minutes to dry the test load of fabric, while ventless models are often closer to 80, or about 30% longer. However, there are outliers, so it is possible to find vented models that are slower at drying than ventless models.

The CEF rating will give you a standard metric by which you can compare the energy efficiency of dryers, but it still doesn’t give you a complete picture, particularly when it comes to the impact on your home’s overall energy usage.

As mentioned before, ventless dryers use conditioned indoor air to dry your clothes, which is eventually vented outside. The impact of this is difficult to estimate because it depends on the outside temperature and your heating and cooling setup. For example, a ventless model will be adding “free” heat to your home in the middle of winter, but that might not be desireable in the summer.

Carbon footprint of gas vs electricity

A final criteria that some may consider is carbon footprint. The Department of Energy estimates that clothes dryers are responsible for about 6% of residential electricity consumption and 2% of residential natural gas consumption. While this may seem relatively small, the DoE states that the cumulative impact of all these dryers adds up to about 60 billion kWh per year, or as much as the entire state of Massachusetts, and 40 million metric tons of carbon dioxide emissions, which is equivalent to about 9 million cars.

If you take a quantity of natural gas and use it to heat a clothes dryer, almost all of the energy from that natural gas will be put to work drying your clothes. However, if you instead burn that natural gas in the most up-to-date combined cycle gas turbine power plant, you will at best convert 60% of that energy into electricity. That electricity will be travel down power lines to your home, incurring further losses along the way.

This means that if most or all of your electricity is supplied by natural gas power plants, it is actually more environmentally friendly to operate a gas clothes dryer than a conventional electric one. However, the mix of fuels used to generate electricity in the US is rapidly changing: solar and wind power are now the cheapest sources of electricity and are replacing fossil fuel power plants, especially coal. According to the EIA, renewables currently make up 21.5% of the US electricity mix and nuclear energy - another non-carbon emitting source - is 18.2%.

The bottom line is that your local electricity generation sources will determine whether drying your clothes with electricity or natural gas will have a lower carbon footprint. If you live in states like Washington, South Dakota, and Vermont - all of which use a high percentage of hydro, wind, or biomass to generate their electricity - even a less efficient electric resistance dryer will have a lower carbon footprint than a gas dryer.

You can use the EPA’s Power Profiler tool to look up the fuel mix for your zip code.

Federal energy efficiency standards for clothes dryers

Here are the current energy efficiency standards published by energystar.gov:

To be able to display an Energy Star label, a clothes dryer must meet these minimum standards and be able to dry a test load within 80 minutes. As a reminder, CEF is a metric of clothes dried per kWh of energy, so higher numbers are better.

The EnergyGuide label isn’t the same as Energy Star certification

One thing that is potentially confusing to consumers is the EnergyGuide label, which is not the same thing as an Energy Star certification.

All types of appliances will include an EnergyGuide label, which displays an estimate of how much energy an appliance will use and what that will cost, based on average utility costs in the United States. If an appliance has an EnergyGuide label, that doesn’t mean it is also Energy Star certified.

Here’s an example of an EnergyGuide label for a dishwasher:

The purpose of the label is to make it easier for consumers to compare the operating cost of appliances.

Appliances that have an Energy Star certification, which is an energy efficiency standard that is better than the federal minimum, will also display this logo:

Will an energy efficient clothes dryer save you money?

Federal standards like the EnergyGuide label help consumers to choose more energy efficient appliances, but they’re only estimates. How appliances are used in the real world can have a big impact on actual energy usage, in much the same way that your driving habits can cause a car to have much worse fuel economy than its EPA rating.

The Division of Energy Resources of the Minnesota Department of Commerce did an in-depth study of actual household usage of heat pump clothes dryers to help answer questions about their real-world efficiency. The study (PDF) is 110 pages long. For those who aren’t inclined to read the whole thing, I’ve summarized some of the key points below.

Real world heat pump savings average around 19%

The Minnesota study included 11 households using 4 different models of compact heat pump dryers, and found that the average electricity usage per load was 2.83 kWh for the heat pump dryers compared to 3.50 kWh for the homeowners’ existing conventional electric dryer, or an average savings of 19%.

However, the savings varied widely, from as low as 4% to as much as 40%. In one case, the heat pump model malfunctioned and ended up using 33% more energy than the conventional dryer. In another case, the heat pump dryer used 12% more electricity because the household was running many short dryer cycles to only partially dry their clothes (presumably because they were drying delicates).

The bottom line is that most homeowners will save energy with a heat pump dryer, but individual habits have a major influence.

Accurate drying sensors make a big difference

One important note that’s relevant to any type of clothes dryer is that perceived drying performance can be affected significantly by the quality of the automatic drying sensor. Most clothes dryers you buy these days have sensors that detect the dryness of clothes and shut off the drying cycle automatically. The Minnesota study and several consumer review sites have noted that the accuracy of these sensors varies, with the effect that clothes dryers can either leave clothes too wet, causing users to add additional drying time, or dry clothes excessively. Both scenarios will waste energy, and potentially more than is gained by switching to a heat pump model.

Small loads waste energy

Another detail noted by the Minnesota study is that 9 out of 10 laundry loads can fit in a compact-sized clothes dryer, but full-sized dryers are the norm. Running small loads in a large dryer wastes energy, and compact dryers are also generally more energy efficient. This means that, regardless of what type of dryer you have, it’s best to run it at a full load.

Heat pump dryers have an additional lint screen that can affect drying performance

All clothes dryers have at least one lint screen to the remove the fluff that comes off your clothes, but heat pump dryers have a second screen that reduces the amount of dust that accumulates on the heat pump itself. Manufacturers have different recommendations for how often the secondary lint trap needs to be cleaned, but for some models it’s as frequent as after every load.

The Minnesota study noted that a clogged filter can have anywhere between no impact and a substantial impact on drying performance, depending on the model. It also noted that there is a question of long term maintenance: heat pump fins may accumulate dust over the long term, even if the filter is cleaned regularly, which could negatively affect energy efficiency.

Take advantage of time-of-use rates to save money

Regardless which type of electric clothes dryer you choose, you can save on operating costs if you have a time-of-use (TOU) plan with your utility.

These are especially prevalent in states with high electricity costs, such as California and Hawaii. If you have a TOU plan, you might be able to save as much as 50% off your electricity costs by doing your clothes washing and drying during off-peak hours. The impact of this is much larger with an electric clothes dryer than with a washer, which uses relatively little electricity.

Most modern clothes dryers have a delay or timer function that make it easier to dry your clothes during off-peak hours. They may also have an anti-wrinkle function that periodically spins the drum after the drying cycle is done to help prevent wrinkles from forming after sitting in the dryer for a long time. (Keep in mind that this this function may add some heat to the drum, increasing energy usage.)

Rebates available for heat pump clothes dryers

The federal Inflation Reduction Act (IRA) offers a federal tax credit for many types of heat pump appliances, including heat pump clothes dryers.

A tax credit worth up $840 is available for heat pump clothes dryers if the household is low to moderate income. This is defined as an individual or family with a total annual income less than 150% of the median income of the area in which the individual or family resides. The Department of Housing and Urban Development reports AMI statistics across the United States.

For details on this rebate, visit this energy.gov web page and click on item #18.

Bottom line: heat pump clothes dryers are a good option for many

Like 80% of Americans that own a clothes dryer, there’s a good chance that you already own an electric clothes dryer. If you’re reading this article, it’s probably because you’re thinking of an upgrade or want to switch from natural gas.

If you’re switching from gas, there’s an excellent chance that a heat pump clothes dryer will save you money. Not only are they highly efficient, but the federal IRA tax credit can knock as much as $840 off the price. For most, they are also the more environmentally friendly choice.

Heat pump dryers are also ventless. For most, this means additional energy savings because you don’t need a vent to the outdoors that steals conditioned air from inside your home. It also means lower installation costs if you don’t have an existing duct, and more choices about where you can install the unit, especially if you choose a compact 120v model.

On the downside, heat pump clothes dryers can have additional maintenance tasks, such as emptying a water collection tank if the unit isn’t hooked up to a drain line, and regularly cleaning a second lint screen. They are also a newer product, and consumers will have fewer models to choose from.

The bottom line is that there are a lot of considerations to weigh when choosing the right type of clothes dryer for you, and there’s no one right answer for anybody. Here’s one last consideration that I haven’t mentioned yet: ventless clothes dryers are higher-end models and may likely come with features and settings that your older existing dryer doesn’t have, such as cycles for sanitizing smelly clothes or steam cycles to help minimize wrinkles. Those things alone may encourage you to upgrade.