I have a Honda EU2000i small generator. When I connect it to the house, it mostly runs on idle. My fridge, chest freezer, TV, internet, DVR and some lights take less that 800 watts combined. Newer appliances are pretty efficient. LED lights are crazy efficient.
Now, when the sump pump or furnace blower kicks on, the little EU2000i revs up big time to handle the load. That is much more than 800watts.