How Clean Energy Charging Works in iOS 16

Introduced in iOS 16, Clean Energy Charging is designed to reduce the iPhone’s carbon footprint by timing battery charges to coincide with periods of cleaner electricity production. This article explains how the feature integrates local carbon emission forecasts with daily charging routines to dynamically manage power draw and prioritize renewable energy.

Local Carbon Emission Forecasting

Clean Energy Charging relies on real-time data regarding the carbon intensity of your regional power grid. When connected to a charger, iOS requests a local carbon emission forecast based on your general location. This forecast identifies when the local grid is powered by lower-emission energy sources—such as wind, solar, or hydroelectric power—versus higher-emission sources like coal or natural gas peaker plants.

Learning Daily Charging Habits

To ensure your phone is fully charged when you need it, the feature operates in tandem with Optimized Battery Charging. iOS monitors your daily habits using machine learning to predict when the device will remain plugged in for an extended period, such as overnight. Clean Energy Charging only activates in locations where you spend significant amounts of time, such as your home or workplace, and will not engage when you are traveling or in irregular charging routines.

Dynamic Charging Optimization

Once the device predicts a long charging window and retrieves the local grid forecast, it schedules the charge:

  1. Initial Charge: The iPhone charges rapidly until it reaches roughly 80% battery capacity.
  2. Selective Pause: If the power grid is currently experiencing high carbon emissions, charging pauses. The system calculates how long it can hold the charge without delaying the expected completion time.
  3. Resuming with Clean Energy: Charging resumes during predicted windows of cleaner power generation, ensuring the battery reaches 100% just before you unplug it.

User Overrides and Controls

If you need your phone fully charged immediately, iOS provides full control over the process. A lock screen notification indicates when Clean Energy Charging is active and displays the time when the device is scheduled to reach 100%. Touch and hold this notification, then tap "Charge Now" to bypass the delay and charge immediately at maximum speed. The feature can also be toggled off entirely in Settings under Battery > Battery Health & Charging.