Many of us don't think about hot water very often — until it's not there when we need it. And almost as shocking as that dreaded cold shower is the fact that heating hot water accounts for nearly 20% of energy costs in American homes.
That can get expensive, fast. Families can easily spend $800 to $1,000 per year on water heating, depending on where they live and what fuel they're using. Almost no one is aware of how expensive it is to heat water — nor how much that energy usage affects our warming planet.
But all of that is about to change.
The newly launched tech company Cala just created what it's calling the world's first intelligent heat pump water heater. (Don't worry, we'll break down those terms in a sec.) Essentially, it can understand your household's unique water usage habits and then "think ahead" to optimize usage and reduce energy costs — saving you money while also minimizing planet-warming pollution.
"A Cala heat pump water heater should be like the most amazing maid of honor or best man at a wedding," Michael Rigney, CEO of Cala, told The Cool Down. When something goes wrong, they "take care of problems without bothering anybody."
In an exclusive interview, Rigney walks us through how this new tech works — and how customers can shave hundreds of dollars off their annual energy bills by making the switch.
💡 How an "intelligent" appliance can save you $$$
We're still in the early stages of intelligent heat pump water heaters like Cala's hitting the market, as there are other companies releasing or readying similar tech, but these appliances are already making waves. That's because heat pump technology is exponentially more efficient than traditional gas or electric hot water heaters.
Cala estimates that the lifetime savings for a four-person family in the Northeast switching from a propane water heater to a Cala heat pump water heater is more than $6,000. The company projects lifetime savings against natural gas ($2,132) and electrical resistance ($5,138) water heaters as well.
As for the "intelligent" part of Cala's heat pump water heater, it uses predictive technology to heat water when your area's energy is cheapest and cleanest, and it can align with a homeowner's solar panels. Think of it like the Nest thermostat of hot water heaters — it even has an app.
"No homeowner I've ever talked to cares about when [their water is] heated," Rigney told us. "You just care that the hot water is there, right? … All of the intelligence that we can bring to bear is valuable, because no one gets upset" to learn their appliance heated the water "three hours ago because that's when the electricity was cheapest or that's when the sun was shining."
"You should tell it what's important to you, and then it should take over," Rigney said.
Typically, conventional tank water heaters last for about a decade. So bottom line, "when it comes time to replace your water heater, the best thing for your wallet and the best thing for the planet is just to buy a heat pump water heater," Rigney noted.
Cala's heaters are currently available to preorder directly on its website, with deliveries beginning in 2025. You can work with a licensed, professional Cala installer (available in many U.S. zip codes), your own technician, or you can DIY it.
❗ Bonus: Those rebates
When it does come time to upgrade your old water heater, homeowners can take advantage of federal and state rebates from the Inflation Reduction Act and related legislation to save even more money. "The bottom line is that this product is directly supported in the IRA, and many states have additional incentives specifically made for heat pump water heaters," Rigney told TCD.
➡️ Here's more info on how to snag that 30% credit from the government.
➡️ And here's a free calculator tool that'll help you get started.
🚿 Redesigning a century-old technology
Welcome to Hot Water Heaters 101. Intelligent heat pump water heaters are a relatively new technology compared to the traditional water heaters many of us are familiar with. Here's a quick refresher on the traditional setup, and then we'll dive into what makes this newer tech so much better.
Lesson 1: Traditional hot water heaters have been around for over a century, and they work by burning fuel to make water hot, typically with oil, propane, natural gas, or electricity — which Rigney calls "a toaster for water, literally."
These water heaters "have no memory and no foresight, and actually, they don't even have awareness of anything else," Rigney said. "They're only aware of one thing, which is the temperature of the water in the tank."
Lesson 2: The "heat pump" part of Cala's heat pump water heater is a slightly newer technology, and even if you don't know it, you're already familiar with it — it's more or less the same tech that keeps our fridges cool and our AC units running. It makes the heating and cooling process more efficient by using heat from the nearby air itself, "taking a gas and … running it around in a cycle using a compressor."
"Essentially we're making that gas really, really hot where we want to send heat, and we're making it really, really cold where we want to absorb heat," Rigney explained.
All of which is to say, "you can get up to 500% efficiency with a heat pump water heater," Rigney said. That means a lower energy bill and less toxic fumes from dirty fuels being burned.
Lesson 3: The Cala team didn't just want to create an uber-efficient hot water system, though. "Instead of just heating up water when it's cold," Rigney wondered, "why don't we take into consideration everything and just optimize water heating for comfort, for cost, and whatever the other priorities are in the home?"
That's where Cala's flow meter comes into play, which tracks a household's typical hot water habits and "understand what's going to happen, what is likely to happen, and [then] to plan so we make a prediction," said Rigney.
🗣️ Which of these factors would most effectively motivate you to buy a heat pump?
🔘 Lower energy bills 💰
🔘 Better temperature control 🌡️
🔘 Helping the planet 🌎
🔘 I'd never buy a heat pump 🚫
🗳️ Click your choice to see results and speak your mind
And adding predictive controls means that if you're gone all day but like to take hot showers after work, for example, Cala can heat water strategically and slowly during the day to reduce energy and deliver the same instant hot water you'd expect.
Or if a storm is predicted in your area, for example, Cala can go ahead and fully heat the water tank ahead of time, in case there's a power outage.
If you need hot water more suddenly, though, Cala's system is built to move faster when demand is high.
"Cala delivers up to 50% more hot water by heating to a higher temperature and then mixing with colder water at the outlet to maintain a consistent delivery temperature to your home," the company says. And because of its intelligent features to heat when demand is low, Cala says that extra heat is basically hoarded up when it's cheaper and meted out gradually as it's needed.
💚 The ultimate goal post
"Our vision is really simple," Rigney told us. "125 million water heaters in America should heat up when the wind is blowing and the sun is shining." And Cala's intelligent system can optimize for that to ensure a cooler, cleaner future.
"That's going to be really inexpensive over time, and it's also going to decarbonize 3% of all greenhouse gas emissions in the whole country," said Rigney.
"Everybody can participate, and everybody can help make that happen," he said. "It's actually really, really achievable."
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