April 25, 2017

At 8 a.m., Marsden Street in Springfield was already a sea of yellow vests and hard hats.Trouble? Not at all.The three largest utilities in Massachusetts were out in force to test the FluxBar, an innovative new tool for measuring gas leaks that Audrey Schulman and Zeyneb Magavi of HEET helped to develop.Steve Bryant, President of Columbia Gas, arranged for the testing, inviting Eversource and National Grid to observe. Because of a new state law, the highest volume leaks—just 7% that emit half of all the emissions—must now be prioritized for repair. However, since utilities have always been mandated to worry only about safety, there is no proven method to find the high volume leaks.Working with Boston University Prof. Nathan Phillips, Bob Ackley of Gas Safety, and Dan Cote of NiSource, HEET set out to design a device to confirm if a leak is a large one and to help utilities learn to find the highest volume leaks.HEET hosted a MIT hackathon and consulted a variety of experts. The problem is complex: gas is invisible, leaks are buried under asphalt, and nothing electronic is allowed in an excavation for fear of explosion. One Harvard professor recommended buying a $100,000 truck that could move a sensor through the plume of gas, but at that price, purchasing and deploying enough trucks to survey 16,000 leaks across the state might cost more than fixing all the leaks.

The FluxBar is the result, based on a common device that utility workers use to vacuum gas from under a street before repair. Brian Ferri of Millibar designed the prototype by decreasing the speed of the vacuum and adding a way to measure the volume of gas gushing out of the leak.Named for this flow or flux, the new tool was ready to test.Dan Cote flew in from Pennsylvania for the test. As Vice President of Pipeline Safety and Compliance for NiSource, the parent company of Columbia Gas, he’s their national gas expert. “Do you know how many meetings I’m skipping to be here?” he asked Audrey. So why did he come?“One of the primary things I need to do is know my system,” he commented. “This tool is a way to do that. Using it takes just 15 minutes. I can see using this on every gas leak across all my systems.”Many leaks, trials and measurements later, it was clear the FluxBar was measuring emissions accurately, providing an apples-to-apples comparison of volume.

Audrey reported:“It worked beautifully! The FluxBar is a utility-friendly, rugged, cheap, safe, and fast method to compare emissions between leaks, so utilities can figure out which ones need to get fixed first.”What’s next? This spring, all three utilities will test the FluxBar on leaks in their territories. HEET will conduct independent measurements to verify the data, then analyze and publish the results.Watch for a preliminary report later this summer and our Super-Emitter Summit to share findings in the fall.