Concerning electrically powered ice protection devices, the only true statement is:
On modern aeroplanes, electrically powered thermal devices are used to prevent icing on small surfaces (pitot-static, windshield...)
On modern aeroplanes, electrical power supply being available in excess, this system is often used for large surfaces de-icing.
On modern aeroplanes, electrically powered thermal devices are very efficient, therefore they only need little energy.
On modern aeroplanes, electrically powered thermal devices are used as de-icing devices for pitot-tubes, static-ports, windshield...