Reservoir's $8M Seed Bets a Water Heater Can Double as Grid Infrastructure

Reservoir has raised an $8M Seed round to do something unglamorous at scale: replace the water heater in the basement and turn the replacement into grid infrastructure. Asymmetric Capital Partners led the round, with Founder Collective and MCJ participating. A valuation was not disclosed.

The Boston company builds predictive electric heat-pump water heaters. Its system combines a heat pump, industrial controls, multiple managed heating elements and software it calls Thermal Intelligence, which learns a household's hot-water patterns and schedules heating toward periods when electricity is cheaper or cleaner — a thermal battery inside the home, without asking residents to plan showers around utility rates.

The product also carries the practical features that decide whether a homeowner cares: leak sensing, app control, time-of-use optimization, Solar Sync, smart-home integrations and over-the-air updates. The Max model adds No-Wait Shower recirculation, rapid recovery, freeze protection and up to 150 gallons of virtual hot-water capacity from a 50-gallon tank.

Reservoir lists Core at $5,000 and Max at $6,500 before rebates, installation included. Massachusetts incentives reduce the displayed prices to $3,950 and $5,450.

The capital will support more installations around Boston, Reservoir's initial market, while the company builds a fleet of connected appliances that can shift electricity use away from expensive peak periods. Reservoir currently serves parts of Massachusetts, southern New Hampshire and southern Maine, but Boston remains the center of the deployment story and the clearest test of whether its integrated model can scale.

Reservoir has installed about 100 systems and is targeting roughly 1,000 by the end of 2027, according to CEO Luke Winston-Almanzar. He says a fleet of that size begins to represent megawatt-scale capacity — a claim that still has to be proven through deployment.

Winston-Almanzar previously helped scale Formlabs, where direct customer relationships mattered when established distribution channels would not embrace a new kind of hardware. Reservoir applied the same approach to hot water by building its own plumbing and installation operation, keeping product feedback, sales, field service and customer experience closer together. CPO Gabriel Parisi-Amon previously co-founded water-technology company Nebia, and CTO Jake Felser brings experience across mechanical, electrical, firmware and software systems.

In the wider market, water heating accounts for roughly 18% of household energy use, making it a large electrical load hidden behind an appliance most people ignore. A conventional tank responds to temperature changes without knowing when grid demand is high. Reservoir's predictive controls can move more heating to off-peak periods while keeping hot water available. Reservoir and Sense demonstrated that grid-responsive approach during Boston Climate Week in May 2026. An aggregated fleet participating in utility demand-response programs remains a future plan rather than established revenue.