Scarborough may power up

The town may replace its boilers with a system that would also produce its own electricity

SCARBOROUGH — With two of the six boilers in his town hall “dead in place,” and the other four living on borrowed time at 20 years old, Scarborough Town Manager Tom Hall says he has “about six weeks” to decide what he’d going to do about it.

The networked system of the boilers, he said, was designed to cycle on and off. With two down, the rest work full time, shortening whatever life they have left. The town could go with the traditional fix, and Hall has budgeted $160,000 to buy three new natural-gas boilers.

But there is an alternate route, which could save money for taxpayers over the long haul and might even come at no cost in the short term. A local businessman has offered the town a custom-built trigeneration unit that would produce electricity on-site, and waste energy would be captured from the process to provide heat and cooling for the building.

“In normal electricity production, 67 percent of what’s produced is waste thermal energy that goes to atmosphere,” Paul Aubrey said on Tuesday.

Aubrey, owner of Self-Gen Inc., has made the pitch that the town use one of his systems, also called CCHP (for combined cooling, heat and power).

“The technology behind this is nothing new,” he added, citing similar tri-gen set-ups at the Eastern Maine Medical Center, the Old Town YMCA and, now under construction, Shipyard Brewing Co.

The problem, however, is that the up-front installation costs for a system suitable to the Scarborough town hall could easily top $400,000. So, since first soliciting Scarborough more than a year ago, Aubrey has in the last few weeks sweetened the deal – he and his investors will install the system for free (primarily to prove its viability to other municipalities) in return for a 10-year contract in which Aubrey will operate the system and the town will buy back the heat and electricity produced on site.

Essentially, the town would be billed what it pays not at current electricity and heating rates, but would get reimbursed for half the difference between that and what the tri-gen system actually costs to run. Aubrey’s investors would get the other half.

“It’s an ‘open book’ mutual-energy agreement,” Aubrey said. “It’s completely transparent. Everybody sees exactly what the numbers are.”

“That’s an exciting option,” said Hall. “No initial outlay is very attractive in what we expect to be a very tough budget year. But it’s also more complicated, at least more so than just plugging in a standard boiler and being done with it.”

But there are other advantages to consider. Aubrey says the tri-gen system would be sized to the heating and cooling needs of town hall. The electricity the system would need to produce to meet that need, at 80 percent overall system efficiency, would more than likely be more than the building can use. That sets up the possibility for what’s called “net metering.” Essentially, any electricity made by the tri-gen boilers not used in town hall could be piped to the high school.

In as little as three years into a proposed 10-year contract, the town could actually be saving enough with its 50 percent rebate and lower costs at the high school to cover all of its utility costs, essentially getting heat and light for free.

“The Public Utilities Commission will let you have up to 10 net meters,” said Aubury, holding out the vision of an even larger system designed to serve the entire municipal campus, including town hall, the high school, the middle school, the public library and Wentworth Intermediate School.

“Maine is 20 years behind the times on this, and this model is perfect for Maine because of we have seven months of heating need,” Aubrey said. By producing its own electricity on site, he said, Scarborough would cut its carbon footprint – the amount of greenhouse gas it contributes to the environment – by 25 percent.

That’s attractive to most on the town’s energy committee, who may get first crack at weighing in on Aubrey’s proposal, when it meets next March 15. At least one member of that group, Debra McDonough, says Scarborough should pay the installation fee out of pocket, in order to cut Aubrey’s company out of future savings.

While Hall argues that having Aubrey invested in the system with “some ownership interest” is a good thing, in terms of ongoing maintenance, McDonough says the town could capture 100 percent of the potential savings, instead of merely the half it would otherwise contract for.

“The fact that they’re willing to put up the capital tells me they’re convinced enough it works to put up cash,” she said, countering Hall at the March 8 energy committee meeting. “That’s a great argument for the system.”

However, because Hall is only weeks away from unveiling his budget for the next fiscal year, the finance committee also will have some say in what happens next.

“The town is playing a balancing thing,” said Councilor Judith Roy, who also serves on the finance committee and as liaison to the town’s energy committee. “We’re holding our breath and saying how long are those boilers going to hang? We have to do something, but do we do something in the short term or the long term? It’s tough.”