When it comes to greenhouse gas emissions, one of the biggest culprits is the personal automobile. But the carbon footprint of real estate is a significant contributor as well.
Buildings generate nearly 40 percent of annual global carbon emissions. Building materials account for about 12 percent; as much as 28 percent is created by operating those buildings, including heating and cooling. In the U.S., about 20 percent of our greenhouse gas emissions come from our homes.
And as the climate warms, there’s the risk of a vicious cycle: with millions more people who don’t have air conditioning buying window units, which contribute to climate change.
But there’s hopeful news. In many climates, people can heat and cool their homes with a single appliance, dispensing with both clunky, loud window air conditioners and furnaces that run on fossil fuels.
The solution: heat pumps. These devices can efficiently deliver both kinds of climate control and create more comfortable environments.
They may not confer the same eco-bragging rights as a sleek electric car or showy rooftop solar panels, but there’s a major payoff.
“A heat pump is probably the biggest thing that consumers can do to help fight the climate crisis,” Amy Boyd, director of policy for the Acadia Center, a research and advocacy organization focused on clean-energy policy in the Northeast, told The New York Times.
War drives talk of a drive toward heat pumps
Heat pumps are in the news these days because of higher fuel prices attributed to the Russian war in Ukraine. Because Europe is highly dependent on Russian oil and gas to heat its homes and fuel its industry, any effort to cut off Russia will raise prices significantly, though talk about it spread in April as evidence of atrocities in Ukraine mounted.
Governments are also offering incentives to get residences to install heat pumps.
It’s an uphill climb. Only 17 million are installed across all of Europe, while in Germany alone, there are some 20 million gas boilers, according to media outlet Euractiv.
But the German government says any heating system installed after January 1, 2025 has to run on renewable energy, widely understood to be an implicit mandate for heat pumps.
And here in the U.S., in late 2021, the Biden Administration pledged to “partner with the private sector to drive innovation in electric heat pumps.” More and more utility companies are rolling out incentives for energy-efficient appliances such as heat pumps.
Again, it’s an uphill climb. The New York Times reported in mid-2021 that they were installed in just 11 percent of homes in the U.S.
What are heat pumps?
Heat pumps use the same principle as a refrigerator or a window air conditioner, by transferring heat from one place to another, rather than generating it. In warm weather, they transfer heat from inside a home to the air outside.
In cooler weather, they transfer heat energy from the cool air outside into the home. They accomplish this by using refrigerant and the simple principle that heat always flows from a hotter place to a cooler one; if the refrigerant is colder than the outdoor air, it can be used to transfer what heat energy is in the air into the home.
Heat pumps are more efficient than gas furnaces in generating heat. Because furnaces operate on combustion, in which some energy is always lost, they are never 100 percent efficient. For space heating, heat pumps can deliver two to four times more energy than the electricity they consume, and new models coming out of Japan are as much as 500 percent more efficient than gas furnaces.
What types of heat pumps are there?
There are three types of heat pump:
- Air-source or air-to-air heat pumps, which exchange the heat between the house and the air outside. This is the most common.
- Ductless air-source heat pumps, or mini-split heat pumps. These work in homes without ducts.
- Geothermal heat pumps, also called ground-source or water-source heat pumps. These transfer heat between the house and the ground or a nearby water source.
What do heat pumps cost? Do they save money?
The cost of a heat pump varies widely depending on the type and size.
HomeAdvisor gives the “typical range” as $4,145 to $7,369. Mini-split systems can cost as little as $2,000, while geothermal systems tend to cost the most — as much as $80,000.
An air-source system for a 3,000-square-foot home will cost about $8,000, including installation, according to Herbert Chu, a senior maintenance specialist with Ram Partners, which manages about 50,000 apartments in complexes nationwide.
A certified air conditioning contractor, Chu has worked with heat pumps for some 25 years.
Except in rare cases, contractors include labor as well as materials and permits in their bids, says HomeAdvisor.
While these are not small numbers, because of greater efficiency, many systems pay for themselves over time, especially in moderate climates.
If it’s regularly serviced, the system Chu described will last 10 to 15 years, he says.
According to HomeAdvisor, homeowners using a furnace may spend as much as $1,550 a year to heat their homes. But using a heat pump in moderate climates, they may spend as little as $260.
Property owners who do have those flashy solar panels, of course, already have the electricity that powers the appliance.
What are the drawbacks of heat pumps?
One major caveat is that homes must be well insulated and weatherized to take full advantage of heat pumps’ efficiency.
There would be two ways to work with a drafty home, says Chu.
“You can renovate the house, sealing the doors and windows, but that’s pretty expensive,” he says. “The other way to approach it is to upgrade your system to compensate for the infiltration of the weather. The drawback to that approach is that you’re going to use a little more electricity. So that comes down to dollars and cents.”
Can heat pumps fully work their magic in frigid climates? It depends who you ask.
A New York Times Wirecutter feature says they’re the best way to heat and cool your home, “no matter the climate.” (Two Massachusetts homeowners attest to this.) The Department of Energy calls them an energy efficient alternative “for all climates.”
Not so fast, says Chu. “You can install it anywhere,” he says, “but you won’t get the full benefit.
“If you’re anywhere north of North Carolina,” says Chu, “you should not install a heat pump, because it depends on ambient air temperature to provide a heat source. Below 34 or 35 degrees, there’s not enough ambient heat in the air for it to work efficiently.
“In that case, you’re relying on an electric heating element to provide the heat, so it’s a double whammy, because you’re paying for the compressor to work and then paying a lot for the heating element to work as well.” (A Washington Post report says that they “perform best in moderate climates.”) Homes being retrofitted with heat pumps could, of course, rely on an existing furnace as a backup in the coldest conditions.
Another proviso for the heat pump–curious is that no one should try to figure heat pumps out for themselves. Local contractors are knowledgeable about various systems, and may even participate in preferred dealer programs created by the manufacturers. They may also be able to offer better warranties, and often can help buyers navigate the sometimes byzantine processes required to take advantage of whatever government incentives may exist.
In fact, according to Chu, it may be best to start the process by finding a recommended local contractor who is familiar with all the complexities of this kind of system, rather than doing excessive amounts of research first. (For example, an old refrigerant is currently being phased out and a new one is coming in, which makes a big difference.) And, incentives may vary not only from state to state, he says, but from city to city, so contractors will be able to advise on whether any incentives will be available for property owners.
Are heat pumps a good investment?
How long will it take for a heat pump to pay for itself based on lower energy bills?
There’s no one metric.
It depends on some factors that don’t stay the same over time, such as fuel prices and energy rates, and some that vary by municipality, such as available tax incentives, as well as how efficient the existing heating and cooling systems are.
An experienced contractor may be able to walk a property owner through determining some of the variables that would help make this determination. There are other eco-friendly upgrades a homeowner can take to shrink their carbon footprint, and those who want to protect their local water supply can look into a green driveway.
Property owners who do invest in a heat pump may see an upside when they put their house on the market.
A 2020 study by the Center for Global Sustainability at the University of Maryland’s School of Public Policy found that the price of the average home was increased by up to 7 percent by the installation of a heat pump, adding on average a $10,400 to $17,000 price premium.
While some might argue that more visible renovations such as a kitchen remodeling (for a sustainable approach, think recycled kitchen) or a bathroom renovation would pay off better, the National Association of Realtors’ Appraisal Journal found that a home’s value may climb between $10 and $25 for each dollar of saved annual energy bills.
The bottom line
Because there are several kinds of heat pumps, and because they are highly customizable for different homes and varying needs, there’s no definitive yes or no answer to whether they are a good investment.
But in view of how beneficial they are for the environment and the potential savings on heating and air conditioning, property owners should research their feasibility.