An internal combustion engine comprising: at least one cylinder defining a combustion chamber in which exhaust gases are generated following the combustion; an exhaust duct, which is flown through by the exhaust gases leaving the combustion chamber; and a system supplying a water-based operator liquid to the combustion chamber comprising: a tank, which is designed to contain a certain amount of water-based operator liquid, and a heating device, which is coupled to the tank and is designed to heat the water-based operator liquid contained in the tank; wherein the heating device comprises a first liquid-liquid heat exchanger, which is coupled to the tank and is designed to heat the water-based operator liquid contained in the tank; the internal combustion engine being characterized in that the heating device comprises: a second gas-liquid heat exchanger, which is designed to be flown through by at least part of the exhaust gases flowing along the exhaust duct; and a hydraulic circuit, which is designed to send round a different exchange fluid completely separate from the water-based operator liquid and from the exhaust gases through the second heat exchanger in order to transfer heat from the exhaust gases to the exchange fluid, and through the first heat exchanger in order to transfer heat from the exchange fluid to the water-based operator liquid contained in the tank. at least one cylinder defining a combustion chamber in which exhaust gases are generated following the combustion; an exhaust duct, which is flown through by the exhaust gases leaving the combustion chamber; and a system supplying a water-based operator liquid to the combustion chamber comprising: a tank, which is designed to contain a certain amount of water-based operator liquid, and a heating device, which is coupled to the tank and is designed to heat the water-based operator liquid contained in the tank; wherein the heating device comprises a first liquid-liquid heat exchanger, which is coupled to the tank and is designed to heat the water-based operator liquid contained in the tank; the internal combustion engine being characterized in that the heating device comprises: a second gas-liquid heat exchanger, which is designed to be flown through by at least part of the exhaust gases flowing along the exhaust duct; and a hydraulic circuit, which is designed to send round a different exchange fluid completely separate from the water-based operator liquid and from the exhaust gases through the second heat exchanger in order to transfer heat from the exhaust gases to the exchange fluid, and through the first heat exchanger in order to transfer heat from the exchange fluid to the water-based operator liquid contained in the tank. a second gas-liquid heat exchanger, which is designed to be flown through by at least part of the exhaust gases flowing along the exhaust duct; and a hydraulic circuit, which is designed to send round a different exchange fluid completely separate from the water-based operator liquid and from the exhaust gases through the second heat exchanger in order to transfer heat from the exhaust gases to the exchange fluid, and through the first heat exchanger in order to transfer heat from the exchange fluid to the water-based operator liquid contained in the tank.