I'm intrigued at the backup possibilities, because we live in a forested area of the northeast where outages are common during storms. But at 3Kw a single unit isn't large enough to power our entire home, and I didn't see a figure for how long it can operate at peak load. If I need two then we're getting closer to the cost of a natural gas fired generator. This analysis, of course, is completely ignoring the environmental benefits.