A cargo transport heating system for a tractor-trailer system comprising a tractor having a combustion engine , and a trailer having a cargo containment , the combustion engine having a first coolant inlet and a coolant outlet ; a heat exchanger disposed in the cargo containment , and in fluid communication with the first coolant inlet ; an engine supply conduit extending between, and in fluid communication with, an outlet of the heat exchanger and the first coolant inlet ; a coolant pump in fluid communication with the coolant outlet and in fluid communication with the heat exchanger ; a supply conduit extending between, and in fluid communication with, the pump and the coolant outlet ; a non-toxic combustion engine coolant, wherein the coolant pump pumps the non-toxic combustion engine coolant through the first coolant inlet , the coolant outlet , and the heat exchanger ; and a controller ; characterized in that the system comprises: a cargo temperature sensor disposed in the cargo containment for measuring cargo air temperature, wherein the cargo temperature sensor is configured to output a cargo temperature signal to the controller ; and an engine temperature sensor configured to measure engine temperature and output an engine temperature signal to the controller , wherein the controller is configured to receive the air and engine temperature signals and based, at least in-part, on the air and engine temperature signals, output at least one command signal to at least one of a flow control valve , the coolant pump , and an engine coolant heater . a tractor having a combustion engine , and a trailer having a cargo containment , the combustion engine having a first coolant inlet and a coolant outlet ; a heat exchanger disposed in the cargo containment , and in fluid communication with the first coolant inlet ; an engine supply conduit extending between, and in fluid communication with, an outlet of the heat exchanger and the first coolant inlet ; a coolant pump in fluid communication with the coolant outlet and in fluid communication with the heat exchanger ; a supply conduit extending between, and in fluid communication with, the pump and the coolant outlet ; a non-toxic combustion engine coolant, wherein the coolant pump pumps the non-toxic combustion engine coolant through the first coolant inlet , the coolant outlet , and the heat exchanger ; and a controller ; characterized in that the system comprises: a cargo temperature sensor disposed in the cargo containment for measuring cargo air temperature, wherein the cargo temperature sensor is configured to output a cargo temperature signal to the controller ; and an engine temperature sensor configured to measure engine temperature and output an engine temperature signal to the controller , wherein the controller is configured to receive the air and engine temperature signals and based, at least in-part, on the air and engine temperature signals, output at least one command signal to at least one of a flow control valve , the coolant pump , and an engine coolant heater . a cargo temperature sensor disposed in the cargo containment for measuring cargo air temperature, wherein the cargo temperature sensor is configured to output a cargo temperature signal to the controller ; and an engine temperature sensor configured to measure engine temperature and output an engine temperature signal to the controller , wherein the controller is configured to receive the air and engine temperature signals and based, at least in-part, on the air and engine temperature signals, output at least one command signal to at least one of a flow control valve , the coolant pump , and an engine coolant heater . <EOS>