Enable efficiency mode when the device is connected to a power source

Allows efficiency mode to become active when the device is connected to a power source. On devices with no battery, this policy has no effect. If you enable this policy, efficiency mode will become active when the device is connected to a power source. If you disable or don't configure this policy, efficiency mode will never become active when the device is connected to a power source. This policy has no effect if the 'EfficiencyModeEnabled' (Efficiency mode enabled) policy is disabled. Learn more about efficiency mode: https://go.microsoft.com/fwlink/?linkid=2173921