iPhone users noticed slow charging. The reason is the new iOS feature

Apple introduced Clean Energy Charging back in October 2022 and turned it on by default. But users have only started noticing it now.

The new feature enables to 'reduce your carbon footprint' by charging when lower carbon-emission electricity is available.

If Clean Energy Charging is on and your iPhone is connected to a charger, your iPhone receives an estimation of the carbon emissions in your local power grid and uses it to charge the iPhone during times of cleaner energy production, like solar or wind.

The feature is available only in the US. Clean Energy Charging in on by default.

To disable the feature:

Go to Settings > Battery > Battery Health & Charging