The archive · Climate & Energy · Strategic decision · 2023–2026
Reservoir bets grid-smart water heaters need its own plumbers
Reservoir pairs a predictive heat-pump water heater with its own install crews — ~100 homes live, $13M raised — betting tanks beat batteries as grid storage.
Reservoir
What the business is
Reservoir designs, sells and installs its own smart all-electric heat-pump water heaters in New England; software learns each household's usage in the first month, then schedules heating for low-price, low-grid hours and detects plumbing leaks.
Starting capital：$13M total disclosed: an earlier $5M seed plus an $8M seed led by Asymmetric Capital Partners with Founder Collective and MCJ (August 2026).
How it started
Luke Winston-Almanzar, former chief business officer of Formlabs, realized he used more energy to heat water than to drive his electric car, and that his air fryer had more intelligence than his water heater. Through the MCJ climate network he met co-founders Gabriel Parisi-Amon (ex-Apple supply chain, YC's Nebia) and Jake Felser (Freight Farms, Eatsa) in 2023 and started Reservoir with an initial $5M seed. The product gathers a month of usage data to predict demand, then runs the heat pump when electricity is cheap or the grid is under strain.
What happened
By 2026-08-12 Reservoir had installed about 100 units in its Boston-area region and announced an $8M seed led by Asymmetric Capital Partners, with Founder Collective and MCJ. The Core model costs $5,000 installed and the Max $6,500; Massachusetts' $1,050 rebate brings Core to $3,950. The company claims savings of up to $1,000 a year for typical Boston homes, heat-pump efficiency roughly 4x electric and 5x gas, a 10-year warranty, ultrasonic leak detection, and up to 150 gallons of hot water from the 50-gallon Max in 'party mode.'
How it ended up
Still live and expanding in its Boston region as of 2026-09-02: about 100 units installed, with a stated goal of ~1,000 by end-2027, when the founder says the fleet starts to represent megawatt-scale flexible capacity.
Background
Reservoir is a Boston hardware-and-service startup selling a smarter water heater: an all-electric heat-pump unit whose software learns a household's hot-water patterns during the first month, then schedules heating when electricity is cheap or grid demand is low — turning a dumb load into flexible storage. Co-founder Luke Winston-Almanzar, formerly chief business officer of Formlabs, notes water heating is about 18% of a home's energy budget and says 'my air fryer is smarter than it.'
The bet has two layers. The first is product: predict demand, shift load, add leak detection and a 10-year warranty so the efficient machine is simply the better machine. The second is distribution: Reservoir started its own plumbing company to quote, permit, install and service the units, because — as Winston-Almanzar learned at Formlabs — distributors resist unfamiliar technology. The Core costs $5,000 installed and the Max $6,500, with a $1,050 Massachusetts rebate cutting Core to $3,950.
By August 2026 Reservoir had installed about 100 units across Massachusetts, southern New Hampshire and southern Maine, and raised an $8M seed led by Asymmetric Capital Partners (Founder Collective and MCJ) on top of a $5M seed. The founder says roughly 1,000 units by end-2027 would begin to represent megawatt-scale capacity and open the door to utility demand-response revenue. The open questions are whether the direct-install model scales beyond New England and whether homeowners replace working water heaters for a payback story.
What has to be true
- Software can turn a fixed appliance into flexible grid capacity without asking users to change when they shower — the same demand-side storage case that batteries chase.
- Heat-pump efficiency (claimed ~4x electric, ~5x gas) plus predictive scheduling attacks the 18% of home energy that water heating consumes.
- Owning installation removes the channel failure that stalled earlier heat-pump adoption: the plumber often decides what the homeowner buys.
- Data from each installed unit gives Reservoir a credible later claim on demand-response and grid-service revenue that a wholesaler-distributed appliance maker would never see.
What can be applied
A novel hardware product can't depend on a channel that won't learn it: owning installation buys customer access, field data, and a later route to grid-service revenue.
Aftermath
As of 2026-09-02 Reservoir is live in its home region: about 100 installations across Massachusetts, southern New Hampshire and Maine, targeting ~1,000 by end-2027 — a fleet it says could join utility demand-response programs. Revenue comes from selling and installing the appliance; grid services remain prospective. Competitor Cala Systems began shipping a predictive heat-pump water heater in September 2025, so Reservoir's own plumbing operation is its clearest edge while it proves density and field reliability.
Sources
- Reservoir raises $8M to make water heaters that people — and the grid — will actually want
- Reservoir raises $8M to scale its in-house water-heater installation model
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