A 10-year-long study of the U.S. oil and gas industry reveals leak of potent greenhouse gas methane amounting to 13 million metric tons per year.
The amount seen in the study is 60 percent higher than the previous estimates given by the U.S. Environmental Protection Agency. The agency previously placed the methane leaks from the natural gas industry at only about 8 million metric tons yearly.
Essentially, the amount of methane loss due to leakage would have been enough to power 10 million homes in the country.
Natural Gas Vs. Coal Fuel
The findings from the present study could invalidate claims that use of natural gas is friendlier to the environment than the use of coal fuels. In comparison, the environmental effect of these methane leaks in 2015 reached the same level of the climate impact of carbon dioxide emissions from all U.S. coal-fired power plants combined in the same year.
The leak was mostly produced from malfunctioning gas equipment and some of the industry's abnormal operating procedures.
Colm Sweeney, the co-author of the study and an atmospheric scientist from the National Oceanic and Atmospheric Administration's Global Monitoring Division, said that the findings recommend devising strategic projects that would end accidental methane seeping.
Another recommendation from the study is for the government to identify the biggest leakers from the U.S. oil and gas industry.
Impacts Of Methane Gas
Methane is the main ingredient of natural gas. However, it is also a greenhouse gas that can warm the planet 80 times as much as carbon dioxide. Methane can contribute about 25 percent to global warming, and its effect can last over the first 20 years after being released.
The study published in the journal Science on June 21 argued that country's total emissions at 2.3 percent of production is enough to compromise the supposed benefit of using natural gas instead of coals. In a business perspective, the methane lost to leakage is estimated to be worth $2 billion a year.
As for the inconsistency between EPA's previous estimates and the findings of the current study, the authors believed the agency missed assessing the accidental sources of methane leaks.
"Instead of coming from the well to the pipeline, the gas is escaping through vents or other openings in the system," said Ramon Alvarez, the lead author of the study and an atmospheric chemist from the Environmental Defense Fund.
Interestingly, there was a policy introduced under the Obama administration that is supposed to regulate methane emissions from the oil and gas industry. However, EPA already announced that it will no longer be implemented until 2019.