Reservoir — a Boston-based manufacturer and installer of heat pump water heaters — is expanding into Maine as hot-water bills continue to climb amid grid strain.
Here's what to know
In a company announcement on October 6, Reservoir said Portland, Maine, will be the first expansion location for the Boston-based company, with more market launches planned for 2027.
The company began residential installations in December 2025 and said it has already installed its heat pump water heater in more than 100 homes, making it one of New England's largest heat pump water heater installers.
The Maine opening is also Reservoir's first move beyond Massachusetts. It is building a local team in Maine and plans to serve households as far as roughly two hours from Portland, including central New Hampshire. According to Efficiency Maine, the statewide total has surpassed 200,000 HVAC heat pumps.
Reservoir also said it is joining The ClimateTech Incubator at Northeastern University's Roux Institute in Portland, which is funded by the Maine Governor's Energy Office.
More background
The move comes as water heating has become more expensive with energy prices near record highs. On top of that, Reservoir said a typical water heater can use more energy over a year than an electric car.
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Maine households face additional pressure because about 66% of homes rely on propane or heating oil, and petroleum product prices are expected to rise because of international conflicts.
Grid pressure was also evident during the summer of 2026. Central Maine Power said heat-related demand surges caused 15,000 customers to lose power.
CEO and co-founder Luke Winston-Almanzar said, "We're building Reservoir to bring comfort and savings to homeowners. Part of that comes from a 21st-century water heater for your home, and part from the fact that Reservoir can help balance the grid without needing consumers to change their habits or utilities to build new infrastructure. The grid has never needed grid responsive devices more."
What's being done?
Reservoir is offering a predictive, grid-aware heat pump water heater meant to cut household energy use while lowering certain home risks.
The company said its system can cut energy use by up to 80% while also helping protect homes from frozen pipes, leaks, fumes, and bacteria.
The upfront price is comparable to a traditional water heater, while operating costs can be up to $800 less per year. The company said homeowners can receive up to $1,150 in combined rebates through Efficiency Maine and the New England Heat Pump Accelerator.
Reservoir said it was founded in 2024 and chose hot water as its starting point because that is the fastest way to make the biggest impact on home energy, resource use, and safety.
John Harry, Reservoir's Portland site lead and head of market expansion, said, "We're proud to partner with local tradespeople and businesses to electrify and decarbonize Maine's homes."
Where can I learn more?
These stories dig into similar rebates and smart water-heating, showing how much modern upgrades can really save you.
• Homeowners can tap $1,700 in government incentives to upgrade to heat pump water heaters.
• Before credits disappear, households can collect over $2,200 in government incentives for super-efficient water heaters.
• In Virginia, the government is offering $400 to upgrade their inefficient water heaters.
• Startups are betting on future-predicting water heaters to help homeowners cut energy costs.
• A new intelligent water heater could save U.S. homeowners over $750 a year.
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