Smart home company Ecobee launched a new feature for its thermostats today that will automatically adjust temperatures to save energy when there’s a risk of a power outage. And unlike some utilities’ energy saving programs, customers will always be able to opt out with Ecobee.

Sudden spikes in electricity demand, often triggered by people cranking up their air conditioning during a heatwave, can lead to power outages. One of the most effective tools utilities have to prevent outages are programs that ask customers to conserve energy during those demand peaks, say, by turning down their thermostats.

Ecobee’s new product update offers something similar to residents in places lacking such programs or who might not sign up for them. It’s an update to Ecobee’s Eco Plus Community Energy Savings feature that will respond to emergency event alerts issued by grid operators in North America.

With this update, customers will get a notification on their Ecobee smart thermostat and Ecobee mobile app telling them there’s a possibility of a blackout because of an energy supply shortage in the area. The thermostat will adjust a small amount, between one and four degrees, for no more than four hours. The feature is designed for customers who haven’t enrolled in a similar program with their utility.

The idea is that many homes taking a small action adds up to a big impact on the grid, smoothing out demand peaks and preempting a power outage. It’s a tactic called demand response that’s supposed to help power grids get more resilient to increasingly extreme weather.

Ecobee allows customers to opt out at any time if they don’t want their thermostat to make the adjustment. Customers enrolled in their utility’s energy saving program don’t always have the same option. During severe energy supply shortages, some utilities don’t allow smart thermostats to override their emergency controls. That’s led to backlash in the past during events like a heatwave in 2022 when thousands of residents in Colorado found themselves locked out of their smart thermostats.

“Everyone has a role to play in conserving energy and helping ensure grid stability,” Kari Binley, Ecobee senior manager of energy partnerships, said in a press release. “This update helps communities take control of their energy savings and avoid potentially dangerous outages during high demand periods.”