Abstract: A hydrogen gas supply system for a hydrogen engine has a hydrogen gas cartridge which is detachably attached to the engine. The cartridge has a casing in which hydrogen gas storage alloy and a heating medium passage for heating the hydrogen gas storage alloy are housed. The engine is provided with a hydrogen gas supply passage which leads hydrogen gas discharged from the hydrogen gas cartridge to the engine, a heating medium supply passage which supplies heating medium to the heating medium passage in the hydrogen gas cartridge and a heating medium return passage through which the heating medium flows out of the hydrogen gas cartridge is returned. The hydrogen gas cartridge is provided with a hydrogen gas takeout port, a heating medium inlet and a heating medium outlet.

Abstract: A hydrogen gas supply system, having metal hydride alloy tanks in which hydrogen at a specific pressure is released within a specified range of temperatures and supplied to a hydrogen engine, is accompanied by a coolant circulation system in which the engine and tanks are connected in parallel, for circulating a coolant through the engine and the tanks. The system executes temperature regulation of the coolant to the tank by mixing the coolant returning from the tanks with the coolant delivered from the engine when the coolant from the engine is at above the specified temperature range.