The Maritime Aquarium at Norwalk cut a ribbon on December 16, 2025 for a piece of equipment almost no visitor will ever see: a combined heat and power system that will take 324 tons of carbon dioxide a year out of the building’s footprint and about $200,000 a year off its utility bills.
The $1.6 million project took 18 months to build. It sits in a mechanical space behind the exhibits, and the guests at the ceremony were walked back there to look at it.
What a CHP system actually does
A conventional building buys electricity from the grid and burns fuel separately for heat. Both processes throw away energy, much of it as heat that is vented rather than used.
Combined heat and power, usually shortened to CHP, generates electricity on site and captures that waste heat instead of venting it. The Maritime Aquarium’s unit runs on natural gas and is paired with an absorption chiller, a device that uses heat rather than a compressor to produce cooling. That pairing is what makes the system earn its keep in both directions: the same captured heat that warms the building in January drives the chillers in July.
The aquarium puts the results at 324 tons of carbon dioxide eliminated annually, an 18 percent cut in its emissions, and roughly 30 percent lower carbon output than conventional energy. It frames the tonnage in a way anyone can hold onto: the same as a year of emissions from 64 gasoline-powered passenger vehicles. The utility savings run 20 to 25 percent, around $200,000 annually.
Why an aquarium cares about its boiler room
“While our typical ribbon-cutting is for a new exhibit or front-of-house experience that our guests can enjoy, this ribbon-cutting celebrates an initiative that in many ways will have a greater impact on their future and our community,” said Jason Patlis, president and CEO of The Maritime Aquarium.
“By instituting a new heating and power system that will be active all year, we will significantly reduce our carbon footprint and lower our utility bills. The Maritime Aquarium is proving that environmental leadership starts at home. Together, we’re showing what’s possible when innovation meets responsibility.”
An aquarium is an energy-hungry building by design. Water has to be moved, filtered, heated and chilled around the clock, and the animals do not get a night off. An institution that spends its exhibit space telling people about a changing ocean has an obvious interest in what its own mechanical room is doing about it, and this is the version of that argument you can put a number on.
Where it fits
The system advances the aquarium’s pledge to reach carbon neutrality by 2035, part of a national climate commitment signed by 24 aquariums on Earth Day in 2022. It also lines up with the aquarium’s 10-year strategic plan and follows a run of similar decisions: in 2014 the institution launched what it describes as the nation’s first battery-powered, hybrid-electric research vessel, and it has been expanding solar since.
In September the Association of Zoos and Aquariums gave The Maritime Aquarium its Green Award for Innovation, a distinction awarded among the roughly 250 accredited institutions in the country.
Patlis was joined at the ribbon by Connecticut Senate Majority Leader Bob Duff, Norwalk Mayor Harry Rilling, and Ayana Melvan, senior director of conservation action for the Aquarium Conservation Partnership, along with trustees, donors and the crews who built the thing.
The project ran through project manager Mark Robbins at MHR Development, with Controlled Air, Westview Group, South Norwalk Electric and Water, and Eversource. Funding came from Chubb, M&T Bank, and Clay Fowler, chair of the aquarium’s board of trustees.
Norwalk visitors will not notice any of it, which is rather the point. The tanks stay the right temperature, the lights stay on, and the building costs the harbor a good deal less than it used to.
More from Norwalk: puffins arrive in Connecticut in Seabirds Between Worlds. And elsewhere on the green-building beat: Zoo Boise wins an international sustainability award.
Quick answers
- What is a combined heat and power system?
It generates electricity on site and captures the waste heat instead of venting it. Paired with an absorption chiller, the captured heat warms the building in winter and drives cooling in summer.
- How much carbon does it save?
324 tons of carbon dioxide a year, an 18 percent cut in the aquarium's emissions, and about 30 percent lower carbon output than conventional energy.
- What did it cost?
$1.6 million, built over 18 months. The aquarium expects to save 20 to 25 percent on utilities, roughly $200,000 a year.
- Is The Maritime Aquarium carbon neutral?
Not yet. It has pledged to reach carbon neutrality by 2035, part of a commitment signed by 24 aquariums on Earth Day in 2022.
