That's true. Currently I have only a single 4kw inverter, so for 240 (stove, a/c, washer/dryer) we have to spin up the 20kw genset. This is silly inefficient, and you are correct that what I would like to have is a small set that will deliver house current while re-charging FULLY the house bank. The latter takes around 8 hours with 75% of that time spent dribbling the final 10% of charge into the AGMs. These batteries will last a very long time if fully charged between cycles but that takes a long time to accomplish, hence my wish for a small footprint 5kw that could still be reasonably loaded when doing its job. Others have suggested the Onan, which is a 2800 rpm vs 1800 for the NL, but is also 40% of the price. I have no clue why there is such a big differential.