A new project has brought together university researchers, an environmental organization and Google to help find and track methane leaks in U.S. cities.

Methane, a natural gas, is commonly used as an energy and heating source, but also makes up about 25 per cent of the greenhouse gases that contribute to global warming. Because it doesn't stay in the atmosphere for long, it doesn't always get the attention that CO2 emissions do.

However, researchers say methane emissions can more easily be reduced, which could have a direct impact on global warming.

The project puts laser-based methane analyzers in Google Street View cars to detect gas leaks from underground methane pipes.

The laser technology allows researchers, like Joe von Fischer from Colorado State University, to see and measure methane leaks in real time.

"It radically changed for me how I could see the world," von Fischer said. "It was like wearing glasses. I could see methane and how it varied."

Colorado State University associate professor Joe von Fischer says the laser-based technology used in the project creates a new tool for quantifying methane gas leaks. (Colorado State University)

Von Fischer first worked with the laser-based analyzers in Fort Collins, Colo., and helped a local company fix a methane leak. He spoke with the Environmental Defence Fund (EDF) about it and was asked to come on board the project the EDF was funding with Google Earth Outreach to lead the scientific end.

"Being able to make really fast, high-precision measurements creates a brand new tool for quantifying methane gas leaks in cities," he said.

Systems already exist for utility companies to find methane leaks, but this project allows more information to be collected faster and easier.

To collect the data, the analyzer box is put in the trunk of the Google car, with a hose to the front bumper. The hose draws the air into the box, which contains the laser which deciphers how much methane is in the air sample, von Fischer said.

"In most of the world we have very little idea about what the environmental quality is like," he said. "In a way, this is a democratization of information about environmental quality on a scale where people live."

Since 2013, the team has gathered and mapped leaks in 12 U.S. cities. Von Fischer said there is a definite difference in the number of leaks in somewhat newer cities like Burlington, Vt., when compared to a city with older infrastructure like Boston, Mass.

Utility companies are usually aware of methane leaks in a city, but many leaks are allowed to continue as long as they are not considered hazardous, something von Fischer said came as a surprise. Not only is methane being allowed to get into the atmosphere, he said, but the resource is also wasted.

The project gives utilities a triage tool for where to make repairs.

"If you target the leakiest parts of the system, you reduce the overall losses of the gas to the atmosphere," von Fischer said.

This map shows some of the methane leaks in Boston in 2013. The yellow dots represents a low leak, which releases between 700 and 9,000 litres of methane a day. A red dot is a high leak, which releases more than 60,000 litres a day. (Environmental Defence Fund/Google)

In Burlington, Vt., the map, from 2014, shows far fewer leaks than Boston, likely because of newer infrastructure. (Environmental Defence Fund/Google)

Project in action

Though not every utility provider was receptive to the data, von Fischer said, one that was keen was Public Service Electric & Gas in New Jersey.

The Google cars spent six months in various parts of the state, and helped PSE&G prioritize replacements to its cast iron piping, some of which dated back to the early 1900s, Wade Miller, PSE&G's gas, transmission and distribution engineer director, told CBC News.

"We know it's aging infrastructure and we know we have a significant amount, there's just under 4,000 miles of cast iron, which is brittle by nature and used archaic construction methods," Miller said.

The biggest difference the company had by working with the project was that it could quantify how much methane was actually leaking, which other equipment wasn't able to do, as it wasn't as sensitive as the laser technology, Miller said.

The first were replacements were pipe leaks that were hazardous, followed by the ones emitting the most methane, he added.

"The environmental benefit was a significant driver of the project," he said. "We wanted to marry risk reduction with methane emissions reduction."

And it's worked. PSE&G reported that in targeted areas it has reduced emissions by 83 per cent, Miller said.