Full Breakdown
Study Finds NYC’s Biggest Methane Losses Come from Combustion, Not Street Leaks
By Drooid · · How we work
New Research Highlights Unexpected Emission Source
A team of Columbia University researchers measured methane, ethane and carbon monoxide at the Mineola monitoring tower that samples air from Manhattan and western Long Island. Their analysis of hourly data from 2023 through 2024 shows that the majority of methane tied to natural-gas use in New York City carries the chemical signature of incomplete combustion, indicating that rooftop boilers, furnaces and gas-powered cooling units are the dominant emitters.
Key Findings and Quantitative Results
- The study estimates that 1.7 % ± 0.6 % of the methane delivered to the city and northeast New Jersey is lost, a rate about three times higher than the 0.5 % loss assumed by local inventories.
- This loss translates to roughly $300 million per year at 2023-2024 retail gas prices.
- Natural gas accounted for 99 % of the methane in February and 85-88 % during the summer months; wetlands, landfills and wastewater plants contributed only a minor share.
- Seasonal patterns showed a winter peak linked to heating, a dip in May, and a second rise through June-August, likely driven by large buildings that run cooling on natural gas.
Policy and Operational Implications
The researchers stress that routine servicing of natural-gas boilers remains essential for safety, but they also call for expanded monitoring of combustion-related emissions. The study suggests that targeting rooftop and building-level combustion sources could address a loss stream that current leak-repair programs overlook, though the exact recoverable portion of the $300 million loss remains uncertain.
Verbatim Quotes
- “As a research community, we were surprised to see that methane emissions from natural gas were related to burning,” — Yuwei Zhao, a PhD student in Columbia University’s Department of Earth and Environmental Sciences
- “We expected winter heating to dominate methane emissions, but the summertime signal showed us that we need to be tracking these emissions year-round,” — Commane. As
- “We don’t yet know how much of the lost methane is recoverable but future research should focus on quantifying the combustion signal,” — Yuwei Zhao, a PhD student in Columbia University’s Department of Earth and Environmental Sciences