Published on November 23rd, 2012 | by Andrew1
“Super-Sensitive,” Mobile Methane Detection Device A Boon For Public, Natural Gas Providers: PG&E Now Using It
Natural gas is the largest source of human methane (CH4) emissions in the country. A greenhouse gas 72-times more potent than carbon dioxide, methane leaks also pose a range of other environmental health and safety risks, from the effects of chronic exposure, to that of explosions. New mobile equipment from Picarro is providing natural gas providers and others the ability to detect the origin and nature of methane leaks much more precisely and on the fly with unprecedented sensitivity.
Researchers recently used a mobile cavity-ring-down CH4 analyzer to map methane emissions across all 785 road miles of natural gas pipelines in Boston. Publishing the results in a report in the Feb. 2013 edition of Environmental Pollution, they found 3,356 methane leaks with concentrations up to 15 times higher than that of global average background levels.
The cavity-ring-down CH4 spectrometer also allowed them to analyze the isotopic CH4 “signatures” of the methane leaks from a subset of all they identified. These strongly indicated “a fossil fuel source rather than a biogenic source for most of the leaks,” concluding that “repairing leaky natural gas distribution systems will reduce greenhouse gas emissions, increase consumer health and safety, and save money.”
PG&E Puts Picarro Surveyor to Work in California
San Francisco-based utility Pacific Gas & Electric (PG&E) says it’s the first power utility in the world to put the Picarro Surveyor to use on a wide-scale basis. On Oct. 1, PG&E announced it was expanding its collaboration with Santa Clara-based Picarro and would deploy six Picarro Surveyor devices to detect natural gas leaks throughout its Northern and Central California service area.
The new, “super-sensitive” devices are some “1,000 times more sensitive than traditional leak detection equipment, capable of detecting leaks down to one part per billion in ambient air while reducing false positives from biological sources of methane,” according to the companies.
They will be mounted on PG&E vehicles, enabling field staff to detect and precisely identify the sources and nature of methane leaks while on the go. This will be a big improvement: not only are the devices more sensitive and precise, analyzing the isotopic chemical composition of leaks can be performed and communicated via the Internet, in real-time.
Walking the Lines
This type of work previously required PG&E field staff to walk miles and miles of natural gas pipelines in search of leaks, using hand-held emissions detection devices much less sensitive and powerful in terms of their analytical capabilities. That should translate into sizable cost savings for PG&E, as well as greater environmental health and safety for workers and the public.
“Picarro Surveyor allows us to not only locate hard-to-find leaks with greater accuracy that we didn’t have before, but it also has the ability to distinguish between natural gas in PG&E’s system and naturally occurring methane,” stated Steve Redding, director of gas maintenance and construction for PG&E.
“By deploying this technology in our service area, we are better equipped to manage our pipeline network and enhance the safety of our customers and employees. We have felt all along this technology would be a breakthrough in our goal to be the safest utility in the U.S., and now that we are using the instrument in the field, it is exciting to see how it enhances our gas operations.”
On Nov. 1, PG&E announced that PG&E field crews using Picarro Surveyor devices mounted on company vehicles in Northern California had located and identified two potential natural gas leaks that the crews had spent months trying to find.
PG&E crews conducted walking surveys, lengthy permitting processes, and seven separate investigative digs. The team was equipped with the mobile Picarro Surveyor located one in Northern California’s East Bay. It proved not to be a natural gas leak, but “a natural breakdown of petrochemicals unrelated to PG&E’s system,” according to a press release.
PG&E began testing Picarro Surveyor devices mounted on two company electric vehicles around nine months ago. “They’ve proven to be so powerful that we are committing to rolling out this innovative technology across our service area,” Nick Stavropoulos, PG&E’s executive vice president of Gas Operations, commented.
“And because Picarro Surveyor will allow us to conduct more frequent and comprehensive surveys, we expect to support the deployment with the hiring of more leak detection and remediation professionals. We’re making every effort to ensure that PG&E is the safest utility in the United States, and Picarro’s technology is a cornerstone to making that happen.”