What will it take for cities to get rid of natural gas?

In Baltimore, where a massive gas explosion leveled homes and killed at least one person on Monday, the utility plans to spend hundreds of millions of dollars to make repairs on the city’s aging natural gas infrastructure. But perhaps making repairs is the wrong plan entirely. Instead, the city could use this as an opportunity to transition away from natural gas entirely.

It’s something that needs to happen anyway, to deal with climate change. To hit a climate target of 1.5 or 2 degrees Celsius, the entire global economy will need to reach net-zero emissions. That includes changing the way that buildings are heated and how kitchen stoves are powered, not only in new buildings, but in every house that already exists. (Gas stoves are also very bad for the air quality in your home.) “The large majority of buildings that will be standing in the middle of the century are already standing,” says Mike Henchen, who focuses on building electrification at the nonprofit Rocky Mountain Institute. “They’re not going to be able to burn fossil fuels if we’re going to reach our climate goals.”

Some cities and states are already beginning to move away from natural gas. In 2019, Berkeley, California, became the first city in the U.S. to ban gas in newly constructed buildings. Around 30 other cities in the state have followed suit. “The focus on new construction policies at the city level is helpful and probably already overdue, even if it’s just getting started,” says Henchen. “But at the same time, retrofits of the buildings that we already have may also need to happen right away.”

That means that gas stoves will need to be replaced by electric or induction stoves, gas water heaters will be replaced by electric water heaters, and furnaces that run on natural gas will likely be replaced by heat pumps, which make use of the constant heat underground to transfer heat inside when it’s cold (in the summer, the process can be reversed to create efficient air cooling). In Maine, the government is paying to help homeowners switch to heat pumps, with a goal of installing 100,000 by 2025. In New York, the state is spending billions on heat pumps as well. Some international governments already plan to go further. In the Netherlands, where natural gas is even more common than it is in the U.S., the country plans to be completely gas-free by 2050.

The more comprehensively the shift can happen, the more it can make cities safer. Around a quarter of gas mains are more than 50 years old. In New York City, a gas main that broke in Harlem in 2014, blowing up half a block of buildings and killing eight people, had been installed in 1887. In Massachusetts, where the pressure in gas lines caused a series of explosions and fires in 40 homes in 2018, one out of every four miles of gas mains were installed before 1940. In Baltimore, where pipe joints installed in the 1950s and 1960s are beginning to fail more frequently, gas leaks increased by 75% between 2009 and 2016. Nearly two dozen leaks are discovered each day, each pumping methane, a potent greenhouse gas, into the atmosphere. (The local utility notes that it isn’t yet clear what caused Monday’s explosion, and the pipes in that particular neighborhood are not among the infrastructure that has been prioritized for replacement.)

Installing new gas infrastructure can’t fully eliminate the risks of the technology and doesn’t solve the climate problem. And yet major investment is happening, including in Baltimore. “There are huge expenses planned to replace leaky pipes with brand new pipes, which would have a very long useful life and presumably some expectation that they’re going to be used to deliver gas for a long time,” says Henchen. “That’s problematic from an investment point of view—that we may be investing large sums of money and more fossil fuel infrastructure which either perpetuates the use of those fossil fuels or at some point it becomes a wasted investment.”

Instead, he says, as cities repair or replace the most dangerous pipes, “you can also start transitioning customers to nonfossil alternatives and build up programs to get entire neighborhoods to switch off gas altogether so that you’re able to start shutting down sections of the gas system. Then instead of investing all the money in replacing a pipe, you can retire it.” The shift can be challenging; in Berkeley, the California Restaurant Association sued over the new gas ban. But the change may still be likely to happen, as cities that have recently passed ambitious goals are realizing that they won’t achieve them with gas in place. “Cities and states are at the point of saying we need to actually execute on this and show how it can be done,” Henchen says. “And they’re realizing they can’t do that while burning all this natural gas in buildings.”