Studies show homes and hotels can be used as grid assets

It’s not a New York City heat wave if the utility doesn’t send customers alerts asking them to limit usage of large appliances and air conditioners. And New Yorkers aren’t alone: In response to mounting energy demand, utility companies across the country are asking customers to curtail their energy use.

These alerts—and the ensuing energy management—are part of demand-response programs, or coordinated ways energy customers can help reduce stress on the grid by using less energy during specific intervals. Customers might be financially incentivized to participate, like by paying cheaper non-peak rates. Two recent reports on demand-response programs, run by energy management companies Renew Home and Parity, showed how homes and hotels can be assets to a swamped grid.

Collective action at home: Both demand-response scenarios used software to curtail small amounts of individual energy use. In the Renew Home study, conducted this summer, 5 million homeowners with Google Nest thermostats opted in to an Energy Shift program in which home temperatures were raised between .5 degrees and 2 degrees Fahrenheit within a two-hour period over numerous randomized trials.

Though the demand-response program relied on smaller-than-usual curtailment per customer, the result was collective action resulting in more than the sum of its parts: Energy Shifts constituted an “aggregate peak day load reduction potential” of nearly 4 GW of energy.

“This resource is not just large; it is predictable and reliable,” the report said of Renew’s Energy Shifts. “Residential demand flexibility can scale beyond highly motivated customers to a mass-market solution that prioritizes user comfort, thereby engaging millions of households to support the grid.”

Grid-interactive efficient buildings: Parity, an HVAC energy management company, has turned hotels and multifamily dwellings into grid-interactive energy-efficient buildings while still prioritizing occupant comfort.

“For property owners in general, but perhaps multifamily and hotel owners in particular, this increase in demand response events could be regarded as a matter of concern or perhaps annoyance, or maybe disregarded entirely,” the study states. “Occupant comfort is paramount. Accordingly, building staff are often reluctant to manually curtail HVAC, particularly on an already hot day, lest they risk upsetting their residents or guests.”

But by automating building heating and cooling with an AI-powered system like Parity’s, rooms are precooled before demand-response events, and then HVAC energy use is curtailed by small, precise amounts. And the program has resulted in significant savings for participants: a 20% to 30% reduction in energy bills.

“It’s not overly complicated, but we’re doing it with an understanding of how far you can go before you might cause a comfort issue, which I think historically has been the missing piece of the puzzle,” Parity’s managing director, James Hannah, said in the report.