Meet Reservoir – The World's Smartest Water Heater
15 comments
·November 15, 2025porphyra
elcomet
Yeah this sounds disingenuous. I can also see my heater to 70C if I want, that does not increase its size...
jfim
It is a scalding hazard though. At 70°C skin burns occur in about a second or so.
The thermostatic valve makes it so that the water that comes out of the water heater is at a more reasonable temperature.
bob1029
I don't think hot water should be this smart.
The last "intelligent" systems that made sense to me in the home are variable speed HVAC and micro grid / solar / battery stuff.
What is the value add to the customer of making hot water an app that can presumably stop working the next time AWS goes down?
Firerouge
A heat pump water heater seems like a no brainer way to improve efficiency. They're not yet common, but there are many more options available over seas than in America.
This project seems emblematic of the challenges facing funding manufacturing initiatives in America. What's funded are the projects that appeal to tech investors, more of a focus on flashy presentation, luxury design, AI, and cloud app features, than the baseline functionality.
We get innovation as a side effect of convincing investors that the idea will disrupt industries and create app ecosystems that lock in consumer attention. Chasing the 100x unicorns and no longer training workhorses
Maxion
Big problem in the US is that in many regions natural gas is cheaper than electricity, causing heat pump water heaters to be more expensive for the consumer. So everyone ends up burning more.
Youden
That doesn't make a lot of sense. A modern gas-fired plant is ~50% efficient and heat pumps typically have a COP of ~3 for hot water, so if you take natural gas, burn it to convert it to electricity, then feed that electricity to a heat pump, you'll get ~1.5x the energy you'd get if you just burned the natural gas.
nrhrjrjrjtntbt
What about heat pump and solar. Maybe just a financing issue then? Maybe installation issue for appartments and rentals.
3eb7988a1663
The pricing page does not make it clear how much the actual unit costs, just $6500 with installation. Never purchased a water heater, but going to Home Depot, I see traditional options priced $500-$2000.
Which says you are putting up a high upfront cost, hoping to recoup on increased efficiency. Which could be worthwhile, but you would have to run some simulations if the price is worthwhile. Seems potentially easier to get a dumb water heater to run extra hot using off-peak electricity.
ChadNauseam
Pretty cool. Reminds me of Impulse. I think there's a big market for home appliances that have more care and attention to detail than we're accustomed to. No one I know is overly satisfied with their water heater.
elcomet
The heat pump will pull heat from inside the house? This sounds terrible for efficiency in winter, as you will need to reheat the room
nrhrjrjrjtntbt
Where does it day that? Would be great if it chose inside or outside based on target inside temp (e.g. cools indoor air in summer to heat water for washing and showers)
Ekaros
Looking at pictures it must pull heat from ambient air or from electricity. There is not enough tubes to have internal and external heat exchanging units.
swiftcoder
... I may be out of touch with US water usage, but just how much hot water does the average household use?
They quote $2,500 10-year savings vs oil. I have my hot water piggybacked on the oil-fired condensing boiler unit that's also used for my central heating, and I doubt I burn more than $250/year total on the hot water side of the equation (in a 4-bed, 4-bath house).
MrLeap
Not interested until it can also show ads.
Interesting but federal tax credits for heat pump water heaters is ending next month [1]. It looks nice though.
For people wondering what's up with the "150 gal virtual" capacity, it's actually a 47 gal water heater but it heats water to a really high temperature (if needed) and mixes it with a thermostatic valve to output the desired temperature. For example if cold water was 15 degrees C and you want the hot water to be 40 degrees C, it can triple its "capacity" by heating it up to 90 degrees C and then mixing one part hot water with 2 parts cold water to give you three times as much hot water. Of course, this comes with a grave penalty to efficiency so you should only do it for "party mode".
[1] https://www.energystar.gov/about/federal-tax-credits