Updated September 29, 2016 at 8:50 a.m. to include corrected information from Burlington Electric about greenhouse gas emissions.

Several major Burlington institutions are backing a plan to create a district heat system that would harness waste heat from the Joseph C. McNeil Generating Station.

A group of residents has been trying for decades to convince city leaders to implement this type of system, which works like an electric grid — but for heat. The idea has been formally studied at least six times, with the most recent report concluding that it didn't make financial sense.

Now, city officials say the calculus has changed because the Burlington Town Center has joined the University of Vermont and the UVM Medical Center in supporting the project. If built, they would depend on the system for heat transported from the biomass plant through an underground system of pipes.

Surprisingly, Vermont Gas Systems is also backing the proposal. It would eliminate some of its biggest natural gas customers, but the company could pick up other business in the process — laying the pipes for the system, for example.

Vermont Gas, the mall, the medical center, the university and the Burlington Electric Department have hired Corix, a Canadian company with experience constructing and operating district heat systems, to study — one more time — whether it's financially feasible in Burlington. They have asked Corix to deliver a "definitive roadmap and implementation strategy" by June 2017 and are splitting the initial $75,000 cost five ways.

There's little doubt that the district heat system would be environmentally advantageous. Corix has already estimated it could reduce Burlington's greenhouse gas emissions by 20 percent. In addition to harnessing heat from McNeil, the system would rely, to a lesser extent, on energy sources such as solar, geothermal and natural gas. 

At the press conference, which was held in front of the Burlington Town Center, Mayor Miro Weinberger, BED director Neale Lunderville and city councilor Karen Paul all stressed that buy-in from Town Center's owner, Don Sinex, was key. "We would not be here today if not for that development," Paul said. 

Weinberger scheduled the event on the eve of a key vote on Sinex's proposal to redevelop the mall. Tomorrow night, the city council is expected to approve a zoning change Sinex has requested and place it on the November ballot. The outcome of that vote — along with a vote on using $22 million in tax increment financing — could determine the fate of the Burlington Town Center project. 

During a subsequent interview, Weinberger said the mall redevelopment wasn't driving the timeline for the district heat project, but he acknowledged that he had wanted to share the news in advance of the vote. "I’m very happy to be able to bring this news forward at this time, as the community is on the cusp of making an inalterable decision about the future of this property."

Some of the staunchest supporters of district heat, including Jan Schultz of the volunteer group Burlington District Energy Service spoke at the event in support of the plan.