BOE Considers HVAC at Hamilton Ave School: “Morally Wrong to Throw Away a Geothermal System?”

Neighbors of Hamilton Avenue School continue to voice frustration over the noisy temporary HVAC system operating outside the school.

At the Sept 26 Board of Selectmen meeting, neighbors asked for updates.

The temporary system was rented by the Board of Education at a cost of $20,000 per month after the 20-year old geothermal system failed in 2023.

Lisa Wynne Salvatore who lives next door to the school said the ongoing noise had become unbearable.

She noted that the Health Dept had been in charge of the town’s Noise Ordinance when she first inquired about the loud machinery, and that Health Dept director Caroline Baisley had approved an emergency variance for the noise.

Since then, the Noise Ordinance moved to the purview of the Selectmen.

“What constitutes the length of an emergency,” Ms Salvatore asked.

“The equivalent of a chain link fence with Saran Wrap is put around it to supposedly be environmentally correct and deafen the noise, but it hasn’t done so at all,” she said. “And recently it has been going on and off, and on and off so it sounds like a siren.”

“What is the plan?” she asked, noting the noise was far above the allowable decibels in the town noise ordinance.

“Usually an emergency variance has a timeline, and a window,” First Selectman Camillo said.

Selectwoman Lauren Rabin said a solution was being held up because the RTM had been reluctant to approve an appropriation for a new gas-fired system to replace the existing geothermal HVAC .

In January the RTM postponed a decision on a $3.2 million request by the Board of Education for a gas-fired system, and asked for a deeper analysis of reusing the geothermal system.

They did approve $411,055 to fund the emergency HVAC rental system for the school until a permanent solution could be found.

Then, in April, a non-binding sense of the meeting resolution in the RTM had the goal of keeping Net-Zero conversations an active part of town and school building projects.

As for the noisy temporary system, Camillo said, “I think the residents are being held hostage here.”

Another neighbor, Catherine Terranova, said, “We are not exaggerating that it is extremely loud…One of the reasons I left New York City was because of the noise, and moved to Greenwich because you can hear birds and bugs and crickets, and I love it. There is a standard of living that people associate with Greenwich that should be upheld.”

Board of Education Discussion

Later in the day of the Selectmen meeting, the Board of Education’s agenda included a presentation from AECOM on their preliminary evaluation of the school’s disused geothermal system.

During the public comment, Peter Schweinfurth, chair of Greenwich’s Energy Management Advisory committee, said his committee members were passionate about their work advising town on improving energy efficiency, decreasing costs and reducing its carbon footprint, and included HVAC and geothermal professionals.

Mr. Schweinfurth said EMAC had been left out of recent discussions, but were eager to help explore leveraging incentives from the Inflation Reduction Act as well as and federal and state grants, which he said could significantly offset replacement costs.

Schweinfurth said Greenwich Schools spent over $3,250,000 on energy in fiscal 2024, which was a 28% increase over fiscal 2020.

“We believe there are real opportunities to reduce these costs, and this project is just the beginning,” he added. “Our vision is to help bring the Hamilton Avenue School building back to what it was originally designed to be – a clean, energy efficient, affordable and easy to operate building that is resilient for the future.”

Michael Doherty and Rob Imparato from AECOM said their report estimated the cost to replace the existing geothermal system with a conventional chilled water system and new boilers was $3,318,115.

Their estimate to reuse the existing geothermal well field and a new mechanical system configured to work with the existing geothermal field and employ an alternate approach inside the building was $3,947,300.

The difference is about $800,000.

The report said it was not possible to completely determine why the system failed, but they suspected it was underperforming due to the two-pipe change-over system and its controls.

“Especially during the shoulder seasons where system demands may require heating in the morning and cooling during the day, the entire volume of water within the two-pipe system would have to flip over from high temperatures, over 120° F, to lower temperatures, below 60° F, which could overwork the compressors and cause premature failures. That coupled with over-pumping the geothermal field with high horsepower pumps would lead to geothermal field overheating and poor temperature control,” the report said.

Greenwich Schools COO Ben Branyan said eligibility for grants was uncertain because the way the Investment Tax Credit and Inflation Reduction Act were written specifies grants are for new systems.

He acknowledged that if a decision was made to repair the existing geothermal system, the work might qualify for an energy tax credit, which would change the overall calculation of the analysis.

The AECOM report said a preliminary estimate for Investment Tax Credit (ITC) was between $1.2 million and $1.6 million.

BOE member Sophie Koven said there were many outstanding questions, given the difference in price between repairing and replacing was “a big swing.”

“I have real pause, I know AECOM did not do the pricing for the conventional system. They said it was done by another firm back in 2023, and you did some escalation to that cost,” Ms Koven said. “But I want a high degree of confidence in what it would cost to fix the geothermal system, whether rebates are available and what is it really going to cost for a new, conventional system before we try to make a decision.”

Finally, she wanted to know if the timing of construction one type of system would be less disruptive to the students.

Greenwich Schools facilities director Dan Watson said he was confident in the engineering firm LiRo’s 2023 estimate for a new, traditional system.

“We contracted with them to do that, but they stopped at 60% of design,” he said. “I spoke to their team today and they have a high level of confidence in the number they provided.”

As for construction time for a new conventional HVAC system, Mr. Branyan said, “We are two to three months ahead of where geothermal would be because of the work that was already done.”

Board member Kathleen Stowe pushed back.

“It doesn’t feel right to go and scrap an expensive geothermal system…It feels morally wrong to throw away a geothermal system.”

“Geothermal is supposed to have a high upfront cost, and a low operating costs. I understand now why the operating cost on a relative basis aren’t as low as they should be,” Ms Stowe added. She went on to question any assumptions that fuel costs would remain low over 25 years.

She added, “There has to be some grant out there to refurbish a geothermal system, because that’s the way the world is going now. …I suspect there is something.”

Ms Stowe added that the RTM‘s April 2024 SOMR about Net-Zero had been “loud and clear.”

BOE acting chair Karen Hirsh said the board’s first and foremost responsibility was to the education of students, but also to support school facilities.

“We need a lot more detailed information when it comes to the budget because nobody wants to throw the baby out with the bathwater,” she added.

Dr. Mercanti-Anthony said while grants would be welcome, even in the worst case scenario based on the independent analysis, “We’re looking at the cost of making the existing geothermal system operable – it is going to cost $800,000 over 25 years. That’s $32,000 a year. Let’s not get carried way. That’s not big numbers.”

He said he viewed the two estimated prices as equivalent and that the price of gas in 20 years was unknown.

Mercanti-Anthony also noted that impassioned members of the RTM believed firmly in investing in geothermal.

Further, he added, “The externalities around pollution are not in that $800,000 calculation, and they should be.”

“I am not a yes vote for the traditional chiller,” Mercanti-Anthony said. “Given these numbers, if behooves us to move forward with the geothermal as quickly as possible.”

Ms Kostin disagreed. “I don’t want to spend $800,000 to save – I’m looking at energy consumption over 25 years for both systems – and the savings is $96,000 over a lifetime for the energy cost. The geothermal system is still using a boiler which is fired by gas.”

Also, she said, “We’re further along in the design of a traditional system, whereas we’re looking at 26 weeks for geothermal. Time has a cost. We’ve already been burning fuel. I can’t tell you what it’s costing in fuel and emissions for running the system that we’ve got that’s angering the community.”

She asked about downtime impacting students.

Mr. Imparato said the geothermal work would require some downtime, but could potentially be done over a summer because the goal was to reuse as much as possible.

That said, he did not believe a design would be ready and a contractor on board by next summer.

“I don’t know how we look the BET in the face and say we want to spend extra almost $1 million on top of the money we’re literally setting on fire and burning in the parking lot to save $96,000 on a system,” Ms Kostin said.

“We’re talking about a 25 year lifespan on a system that’s been in the ground 20 years already. Those wells have been there 20 years. Are they going to last another 25? I don’t know.”

Mr. Imparato AECOM said a geothermal field itself had no moving parts and the piping had a 50-year warrantee.

Mr. Imparato said, “It’s the internal building parts and pieces that fail way earlier than a geothermal field will. There’s no concern with that field lasting another 25 years or longer.”

“That’s good news,” Ms Kostin said.

Ms Hirsh suggested BOE questions be forwarded to Dr. Jones, but noted the issue remained time-sensitive and warranted a discussion with BET.

As for the noise impacting neighbors, Mr. Branyan said that through AECOM the BOE had engaged acoustical engineers to look at possible noise mitigation solutions.

He said regardless of the decision made in the future on the system, the temporary system would be in place for a while.

See also:

Patience Wears Thin over Noise from Temporary HVAC at Hamilton Ave School  Aug 21, 2024

SOMR to Encourage Net-Zero Energy Passes at RTM April 9, 2024