What is Apple’s new Clean Energy Charging in iOS 16 and how will it work?

Apple’s got plenty of already-announced features coming to iOS 16 in updates later this year. But in the company’s press release announcing the initial availability of iOS 16 Monday, it announced an upcoming feature we hadn’t heard about yet: Clean Energy Charging.

It was just an offhand mention in a footnote about iOS 16 availability, crowded in with other features we know are coming in updates later this year such as Live Activities, iCloud Photo Sharing, and support for the Matter smart home standard. So we don’t have a lot of concrete information about Clean Energy Charging yet.

Apple says Clean Energy Charging “aims to decrease the carbon footprint of the iPhone by optimizing charging times for when the grid is using cleaner energy sources.” What’s more, a footnote to the footnote says that the feature will be available only to users in the US. Hopefully, it will expand to other territories in the future. Apple doesn’t say whether the feature will be limited to certain iPhones.

Our best guess? Apple is probably partnering to get data from electric grid managers that shows the mix of energy sources powering the grid (for example, see the California ISO supply trend page), or with a third-party source like Watttime that seeks to measure when the electricity you use is powered by cleaner sources.

Throughout a typical day, electricity demand fluctuates, often making it necessary to increase power from on-demand sources such as natural gas power plants. Energy sources like solar and wind produce variable amounts of power depending on time of day and weather. Hydroelectric power often changes with the seasons.

But this is all predictable if you have the data, and it sounds like this feature is going to try to charge your iPhone when the grid is “green,” so to speak. As an example, though you may plug in your iPhone at 9pm at night, perhaps your phone will detect that, based on your past usage history, you don’t actually need to charge it yet, and it would be better to wait a few hours because the power in your area will be generated by a larger percentage of renewables at that time. There will likely be a toggle in the battery settings that lets you turn Clean Energy Charging off.

It’s a feature that is certainly going to need to know not only about the power generation sources in your area, but your charging and use habits throughout the day, because the whole point will be to not start charging immediately if it would be greener to wait, but nobody wants their phone to die because it wouldn’t charge when they plugged it in.

Apple says Clean Energy Charging will arrive in an iOS 16 update “later this year.”