In steam power the water is not the fuel, usually the heat to make the steam move an object is produced by burning coal, alternatives are gas, wood and oil. So the short answer is no.
Steam engines are external combustion engines where the working fuel is coal. Coal is burnt and heat is utilised to boil water, inturn helps in the working of engine. Whereas a petrol engine is an internal combustion(IC) engine where petrol only is used as the fuel. Petrol is burnt under rated pressure and temperature to maintain the equvilibrium of the engine. Considering your question, the answer is yes. But if it is used as an alternate it will make the engine more bulkier and also seperate mechanism has to be included which again make it more and more complex.
Asking if water can be a source (of energy). Answer is no, as you point out they are different, but as an alternative it is more wasteful, more polluting and bulkier.
Steam engines are external combustion engines where the working fuel is coal. Coal is burnt and heat is utilised to boil water, inturn helps in the working of engine. Whereas a petrol engine is an internal combustion(IC) engine where petrol only is used as the fuel. Petrol is burnt under rated pressure and temperature to maintain the equvilibrium of the engine.
Considering your question, the answer is yes. But if it is used as an alternate it will make the engine more bulkier and also seperate mechanism has to be included which again make it more and more complex.