The total solar eclipse that crossed the US on August 21, 2017 was the first of its kind in 99 years. During the eclipse, as less light reached solar panels across the US, solar energy production dropped, meaning more power plants would have to be fired up to cover the shortfall. Because Nest is a brand that’s always cared deeply for the environment, having saved over 22 billion kilowatts of energy to date, we knew we had to do something. So we created an initiative that allowed Nest users to help out the grid and automatically save energy during the eclipse. It was a pretty simple premise that required little sacrifice – Nest thermostats automatically pre-cooled homes beforehand, so they could save energy during the event. We also invited non-Nest users to participate manually via a full-page ad in the New York Times.

Part of what consumers buy into when they purchase a Nest thermostat, is energy efficiency. Additionally, Nest’s mission is to create a home that cares for the people inside it and the world around it. So it mattered that we do something to support clean energy at a time when it was particularly vulnerable.

As 8.21 approached, the idea of pre-cooling homes to hedge the effects of the eclipse was conceived. We were able to accomplish this because of Nest’s long-standing relationship with US energy suppliers. A Nest thermostat talks to the household’s energy provider to get real-time energy usage, and adjust accordingly. We used this technology as the basis of our execution: seamlessly pre-cooling homes in advance of the eclipse to help out the grid at a precarious moment.

While the initiative was hyped in social, earned media and via blog post and email, Nest users were invited to participate directly from the screen of their thermostats. In the lead-up, hundreds of thousands opted in, posting photos & video of the simple iconic graphic on social media.

As the eclipse traversed the United States, solar energy production dropped by thousands of megawatts. That’s when the initiative kicked in. Nest thermostats began syncing energy consumption with the eclipse’s path, using less energy when the grid needed it most. More than 750,000 Nest thermostats worked together to reduce energy demand by 700 MW during the eclipse, making up for over 5% of the lost solar capacity. Put another way, that’s around the same amount of power produced by seven gas-powered peaker plants. So together, it’s like we built a virtual power plant.