NETL launches project to locate methane leaks in gas pipelines
The National Energy Technology Laboratory (NETL) is working on a project to locate and quantify methane leaks in the nation’s natural gas infrastructure.
Gas pipelines cover about 3 million miles, carrying 24 trillion cubic feet of natural gas to 70 million-plus consumers in the United States each year. There are three different types of pipelines: gathering lines, which transport raw natural gas from wells for processing; transmission lines, which move processed natural gas to distribution centers and storage facilities across the country; and distribution lines, which deliver natural gas to customers.
Transmission and distribution lines are well regulated and documented, but there are fewer inspections of gathering lines. This means they are less likely to be mapped or recorded, which means leaks from gathering lines are not as well characterized.
A major challenge in locating gathering pipelines is finding the endpoints, which usually are wells and processing stations. While processing stations are well marked, wells typically are not. Aerial magnetic surveys were found to be the best way to locate the wells, as opposed to searching on the ground. Many of the old wells were not properly sealed when they were abandoned, which created pathways for liquids and gases to rise to the surface or flow underground. When wells are poorly sealed, they can contaminate sources of drinking water and release harmful gases. The same is true with leaking pipelines, which is the focus of NETL’s research.
“In order to more accurately estimate leaks from gathering systems, we should be collecting measurements from gathering systems, not distribution lines,” NETL Technology Portfolio Lead Natalie Pekney said.
NETL conducted a ground survey at Moshannon State Forest near Dubois, Pennsylvania, where low levels of methane were found using methane detection technology. Researchers are examining the possible factors that impact methane leak rates for gathering pipelines, including age, region of the country and pipeline materials.
They are also working to improve methane detection methods. NETL researchers are exploring the use of drones to monitor, measure, detect and document environmental conditions in remote, dangerous and otherwise inaccessible areas using new technology.
NETL will share its findings from the project with the U.S. Environmental Protection Agency.
