The Awkward Climate Win of More Efficient Furnaces

For more than a decade, Americans have been sold inferior furnaces to heat their homes that raise their energy bills and dump carbon into the atmosphere when much more efficient options were available. That’s finally going to change … five years from now.

On Friday, the Department of Energy finalized new, long-awaited standards for gas furnaces that have not meaningfully changed since they were first enacted in 1987. So long as the rule does not get held up in court, or by a future administration, it will require that by 2029, all gas furnaces on the market are 95% efficient. When it was first enacted, the standard was 78%. The current standard, which went into effect in 2015, is 80%.

It’s a bit of an awkward win for the climate movement. On the one hand, it’s a rule that assumes that fossil fuel-fired furnaces will still be on the market through at least 2058, far past the 2050 date by which the U.S. has committed to reduce its emissions to net-zero. Every new gas furnace installed could lock in carbon emissions and local pollution for the 15 to 20 years it operates.

On the other, clean energy and environmental advocates have been pushing for this kind of update to the standards since at least 2007, only to be stymied by lobbying and lawsuits from the gas industry, equipment manufacturers, and other industry groups. Though some states, like New York and California, are starting to phase out the sale of gas furnaces, there’s not yet any plan to do so on the national level. As long as people keep buying them, this rule will go a long way to make sure they emit as little as possible.

“Furnace technology advanced a long time ago, but the standards didn’t keep up,” said Andrew deLaski, the executive director of the Appliance Standards Awareness Project, in a press release. “This is going to guarantee that all new models use proven energy-saving technologies. We won’t keep wasting so much heat for decades more.”

The DOE estimates the updated standard will cumulatively save consumers $24.8 billion on their energy bills between 2029 and 2058. Individual households could save $350 over the lifetime of the equipment, and those living in mobile homes could save more than $600. The agency also says the rule will cut carbon emissions by 332 million metric tons over that period, roughly equivalent to the annual emissions from a third of American homes. It will also cut methane emissions by 4.3 million tons, which is slightly more than all U.S. municipal landfills emit in a year.

Jumping from 80% to 95% might sound like a big leap, but the technology to achieve it has been on the market for decades. A number of states and efficiency advocacy groups tried to sue the DOE when it last changed the standard in 2007 because they claimed that 80% was already too low back then. The vast majority of the products for sale were performing at that level or higher, so the change wasn’t going to do anything to reduce energy consumption or save households and businesses money.

The DOE made several attempts to update the standard under the Obama administration. The big sticking point was a technological quirk. Systems that achieve efficiency higher than 80% use something called a condenser to capture waste heat from the exhaust stream and send it into the building instead. Switching from a non-condensing furnace to a condensing furnace may come with some additional expenses, like the need to move the furnace to a different part of the building and install an exhaust pipe. Opponents argued that any rule that effectively banned non-condensing furnaces was unfair to consumers who couldn’t afford those changes. Under the Trump administration, they argued that condensing furnaces should be regulated as an entirely different product class.

But advocates counter that consumers will save money in the long run with a more efficient system. The updated standard could especially benefit renters, who won’t necessarily be burdened with any potential increase in upfront costs to install a condensing boiler, but will see lower heating bills. The DOE also estimates that when the standard kicks in, about 4.2% of building owners will forgo a new gas furnace altogether and get an electric heat pump, with the help of tax credits and rebates in the Inflation Reduction Act that incentivize this shift. That estimate does not even take into account the fact that furnaces may soon no longer qualify for Energy Star certification , which could push even more consumers to heat pumps.

Though on paper, the standard is expected to make a significant dent in emissions, the fact that it won’t go into effect for five more years — nearly 40 years after the last significant change — will have lasting consequences. Millions of gas-guzzling furnaces have been installed that didn’t have to be, and millions more could be before the standard kicks in. All the carbon emitted as a result will warm the planet for thousands of years.