NEW YORK (NYTIMES) - Gas stoves leak significant amounts of methane when they are being ignited and even while they are turned off, according to a new report, adding to the growing debate over the effects of gas-powered appliances on human health and climate change.
The small study - based on measurements from cooktops, ovens and broilers in 53 homes in California - estimated that stoves emit between 0.8 per cent and 1.3 per cent of the natural gas they consume as unburnt methane, a potent greenhouse gas. During the course of a typical year, three-quarters of these emissions occur when the devices are shut off, the study showed, which could suggest leaky fittings and connections with gas service lines.
Over a 20-year period, emissions from stoves across the United States could be having the same effect in heating the planet as half a million gas-powered cars, the study estimated.
"People are so attached to their stoves," said Dr Eric Lebel, a senior scientist at the non-profit research institute PSE Healthy Energy and the lead author of the study, which was published on Thursday (Jan 27) in the journal Environmental Science & Technology. "There's something human about cooking on a gas stove, over an open flame."
But more and more evidence, he said, suggests that stoves are "damaging health and climate all at once".
Growing numbers of US cities, largely in Democratic-leaning states such as California and Massachusetts, are shifting homes away from gas-powered cooking and heating. New York City has banned gas hook-ups in all new buildings. But at least 20 mostly Republican-leaning states have barred cities from restricting gas use, often with the support of natural gas companies and utilities that see electrification as a threat to their bottom lines.
There were more than 40 million gas stoves in US households in 2015, the last year for which there is detailed data from government surveys. In total, homes and buildings are responsible for an estimated 13 per cent of America's greenhouse gas emissions.
Methane is the main component of natural gas, and if it is not burned when released, it can warm the earth more than 80 times as much as the same amount of carbon dioxide over a 20-year period. Methane also contributes to ground-level ozone pollution, which can cause breathing problems and other health issues.
Methane leaks from oil and gas installations have attracted increasing attention in recent years, and efforts are under way to plug thousands of inactive, methane-spewing oil and gas wells across the country.
