Have all the circuits at my house on Mains power from the local power company.
Install an alternate source (wind solar etc) and put it through an inverter to make good enough sine AC to power the heat and light circuits.
These would need to be dedicated circuit powering only "insensitive" devices/loads.
When the power output from alternate source(s) is high enough, have a break before make switch cut from mains to alternate power. When the alternate power source backs off again, cut back to the main circuit.
HGas this been done - does anyone know of suppliers of gear for this arrangement?
Due to laws in New Zealand it really is very uneconomic to grid tie an inverter - a long story, but trust mne... there is little money to be saved, and I don;t think there would ever be a payback if any interest is applied to the initial investment capital.
I look forward to thoughts and opinions.