US Patent 9850873 Engine pre-heating system and method for multiple vehicles

An engine pre-heating system includes a housing that houses a climate control heating element and a controller configured in the housing. The controller generates an energizing signal for controlling an amount of electrical power provided to multiple engine heating elements that are thermally coupled to the engines of multiple vehicles. The controller also generates a climate control signal for controlling the climate controlled heating element to maintain the controller inside the housing within a specified temperature range. The energizing signal provided to the engine heating elements is inversely proportional to an ambient temperature proximate the engines.