We are currently evaluating an off-grid hospitality project in Mexico. The project is primarily powered by a 32kW PV array which is sometimes supplemented by a propane generator. Except for the propane receipts, we are obviously not getting any utility bills. My first inclination was to simply add the kWh produced by the PV inverters to the propane consumption. However, in cases where the PV array was actually producing more than what is needed, this number would be higher than actual building consumption.

My second inclination was to submeter all building systems (and not included generator/PV array inputs). Can anyone confirm that this would be an appropriate approach? Does anyone have experience with off-grid projects pursuing this credit?