In exchange for a more substantial energy-bill savings (5-10% of the summer's air-conditioning tariff), participating customers agree to an "Auto-Tune" of their Nest, a three-week adjustment period where the algorithms plan a regime that routinely rejiggers air-conditioning use during the day.

CNN: Nest's plan to stop brownouts before they start

The most basic service takes advantage of Nest's existing technology, which features an Auto-Away process that learns the users' schedules and adjusts temperatures when no one is home.

CNN: Nest's plan to stop brownouts before they start

Indeed, NRG's CEO David Crane recalls the first time he visited Nest at its Palo Alto headquarters, where the parking lot is ringed with high-speed auto charging ports.

CNN: Nest's plan to stop brownouts before they start