Patent ID: 8600615

Claim:
A method of achieving a temperature in a cabin of a hybrid vehicle having an internal combustion engine employing a coolant to remove engine heat, and a heating ventilation and air conditioning (HVAC) system using the coolant to heat the cabin, the method comprising: detecting a request to achieve a predetermined temperature inside the cabin; selecting a first baseline mode of operation of the engine to supply thermal energy to the coolant; selecting a second mode of operation of the engine wherein the engine is run more frequently relative to the first baseline mode of operation to supply additional thermal energy to the coolant if the predetermined temperature has not been achieved via the first baseline mode of operation; and selecting a third mode of operation of the engine wherein the engine is running and combustion of fuel in the engine is varied to supply additional thermal energy to the coolant if the predetermined temperature has not been achieved via the second mode of operation; wherein each of said detecting the request to achieve the predetermined temperature inside the cabin, selecting the first baseline, the second, and the third modes of operation of the engine, and monitoring the desired temperature of the coolant and the actual temperature of the coolant is accomplished via a controller.