The wattage will depend upon exactly what you want to run. If you really mean your whole house then your probably gonna be looking from 17k to 20k for the wattage. Example: I use a 6500w generator at my house for when we lose power. It is enough to run all lights, fridges/freezers and our well. Anything more than that will trip the generator. So no heat, no ac, no dryer, no water heater. I am interested in what your plans are? I have a creek and have been toying with the idea myself for the last year. I just haven’t had the time to dedicate to it yet beyond thinking some ideas thru in my head. Some of our monthly power bills this winter though have moved the project up higher on my list of a million things to do. Let me know your thoughts, happy to help if I can.