At this price it would never pay for itself, but an offsetting benefit of this battery system is, or at least might be, that for those of us paying time-of-use electric rates who also cook and eat dinner at dinner time, induction cooking is surprisingly expensive. If this thing can charge itself off-peak, and use its battery even when the grid is available, that could save a dime here and there. My summer peak-hour marginal cost is 54¢/kWh.