BPA has added two models of smart thermostats to its list of approved energy-efficiency products, and is promoting energy efficiency by providing technical support and financial reimbursement to 142 public utilities around the four-state region for a portfolio of qualified improvements that save power in homes and businesses in its partner utilities’ service areas. The products range from light bulbs to appliances to heating and cooling systems.
Compared to previous generations of programmable thermostats, smart thermostats offer greater benefits and less effort to use effectively after set-up. Devices such as the Nest and Ecobee, the two on BPA’s list, learn their household’s preferences and schedules to operate the heating and cooling system in the most comfortable, efficient pattern to complement the residents’ habits.
In a pilot BPA ran with Frankin PUD, homes saved an average of 12 percent in their electricity consumption for heating and cooling (841 kWh), reducing their total electricity use by 4 percent.
Homes that used more electricity before getting the Nest saw more energy savings. And households that used lower heating set points, higher cooling set points and more aggressive settings also achieved more savings.
The residents were generally happy with the devices, based on a survey. Most households were satisfied with the Nest’s usability and the level of comfort it provided. Nearly 90 percent of participants indicated they were “somewhat” or “completely” satisfied, and 75 percent said they were “somewhat” or “completely” likely to recommend the smart thermostat.
BPA’s Phillip Kelsven, an economist and EE planner, said that the Nest thermostats helped optimize heat pump’s cycling, controlling the standard cycle to wring out more efficiency. BPA’s Kelsven, Robert Weber and Eva Urbatsch published a paper on the pilot for the American Council for an Energy-Efficient Economy. Engineer Tom Osborn and others from BPA teamed with Franklin PUD’s Todd Blackman and CLEAResult’s Bruce Manclark and Mark Jerome on the project.
While the study focused on air-source heat pumps, which account for the systems in about 40 percent of homes in BPA’s territory, Kelsven says smart thermostats can offer value in other homes, as well. “It’s also a good complement to forced-air furnaces, either gas or electric,” he says. “It’s probably going to offer a lesser percentage of savings (compared to homes with air-source heat pumps), but still a good savings.”
An additional perk: Smart thermostats are compatible with not only smartphones, but the increasingly popular voice-operated speakers such as the Amazon Echo and Google Home.
“We believe these intelligent thermostats are only the beginning of a new generation of smart communicating products that will improve the homeowner experience, energy savings, comfort and security,” says BPA’s Robert Weber, engineering technical lead. ♦