Cala Fleet ReportFirst year · Data through September 28, 2026

The first-year fleet report.

One year, hundreds of homes, every shower and dishwasher cycle: Cala’s been actively saving homes energy without compromising comfort.

Every Cala measures its own electricity and hot water use. This report publishes that data: 312 homes and nearly half a million hot-water uses. It is the largest field dataset of its kind, and the first ever published by a water heater maker.

At a glance

$182/yrAverage cost to heat a home’s watervs. about $231 for a conventional heat pump water heater, both at the U.S. average of $0.18/kWh
99.7%Of the time, hot water was available when neededOut of nearly half a million measured uses
93%Of the heat came from the heat pumpvs. about 65% for conventional heat pump water heaters
167MWhElectricity saved vs. electric water heatersAbout a year of electricity for 15 average U.S. homes

The fleet, added up

Year one, across every home.

312

homes reportingAcross the country, each joining as it was installed

1.45M

gallons of hot water deliveredEnough to fill two Olympic swimming pools

1.09M

operating hoursAbout 124 years of running, added together

28–122°F

air temperatures the fleet ran inFrom cold basements to hot garages

Month by month

Ample hot water no matter the season.

Average kWh per Cala home each month, October 2025 to September 2026. Winter takes more energy because the incoming water and the air around the unit are colder.

84 kWh a month

The average Cala home, across the whole year.

Each month is weighted equally, so the many homes that joined over the summer don’t pull the figure down. At the U.S. average electricity price, that is about $15 a month for all of a household’s hot water.

Winter monthsRest of the year

Why it costs less

The heat pump does the work.

A heat pump water heater has two ways to make heat: the heat pump, and a backup electric element. The heat pump makes about 2-4 times as much heat per kWh, so the more of the work it does, the lower the bill.

Cala

93% from the heat pump

Cala Predictive Intelligence™ learns when your household uses hot water and plans its heating around it. Its variable-speed compressor lets it start early and run gently at low speed, then ramp up when the household needs more, so the heat pump covers the load and the backup element is rarely needed. Even the heaviest-use homes (52+ gallons a day, about one in seven) got about 85% of their heat from the heat pump. Heavy users in the NEEA study got half or less.

Conventional heat pump water heaters

About 65% from the heat pump

A conventional heat pump water heater reacts once the tank has already cooled. When demand comes in a rush, it falls back on its electric element to catch up. In a field study of 57 metered homes, that left the heat pump doing only about 65% of the work.Larson, 2026

When is a heat pump water heater not really a heat pump water heater? →

What that adds up to

84 kWh a month for Cala, against 107 for a conventional heat pump water heater.

Same hot water, the gallons and water temperatures we measured in Cala homes, heated two ways.

21% less

Less electricity than a conventional heat pump water heater heating the same water.

$182a yearto heat a home’s water with Cala, at the U.S. average of $0.18/kWh
1,013kWh a yearof electricity for all of a home’s hot water

How we compared. Cala’s 84 kWh is measured. The 107 kWh is an estimate for the same hot water from a conventional heat pump water heater, based on available published field data. No other studies at scale have both metered water and energy usage.

Hot water, every time

99.7%

of showers, baths and tap uses ran hot.

Saving energy only counts if the shower stays hot. Across nearly half a million measured hot-water uses, 99.7% were delivered hot.

“Absolutely zero problems. Tons of capacity. Super efficient. It’s operated in heat pump mode exclusively 100% of the time.”

★★★★★ Reid, New York

“This is my second heat pump hot water heater and the Cala quality is head and shoulders above the ones sold in the big box stores.”

★★★★★ Chuck, Maine

Next step

Put year two in your home.

Check whether a Cala Pro covers your ZIP code, and what an installed price looks like for your house. If you’d rather use your own plumber, Cala will support them through the install.

Order Cala Find a Cala Pro
A Cala heat pump water heater installed in a bright garage

How we measured

These results cover Cala homes across the country reporting from September 1, 2025 to September 28, 2026. Homes joined throughout the year, so most were monitored for less than twelve months. Electricity use, hot water and temperatures are measured by each Cala water heater. Comparisons with other water heaters are estimates based on published field data.

$182 a year for hot water, measured.
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