I never anticipate wanting to give power back to my local utility. However, I was somehow under the impression that in an off grid situation, the "bidirectional" power flow capability to the (now absent) utility is nonetheless potentially useful, but I'm having trouble seeing how. Is it just that it could be used simply as another A/C output? At the risk of ridicule, I'll ask: In an off grid situation, what about having two such AIO hybrid inverters (w/ separate panels and batteries) , not paralleled, but connected to each other via their unused hybrid grid-tie inputs/outputs? Back up battery bank? Does this add any advantage to just paralleling them w/ same number of panels and batteries?