BFL, for years I have been convinced (though actual trial-and-error) that solar panels equivelant to 10% of total amp hour capacity offer just about the optimum balance of generator and solar. This is, of course, providing the skies cooperate and vacation is not during winter solstice.
My 3,300 amp hour bank would demand quite a number of panels to get me liberated from the Kubota or Lombardini. 330 amperes @ 28 vdc to be exact. Ten 33-ampere feeders to a buss bar. To say this is a little beyond my budget would be the understatement of the decade. Thankfully I have public power 70% of the time.
The bell-curve at this latitude allows an average of 5.5 hours with >80% theoretical max potential of panel output. Thankfully the bank is not stressed beyond 1,100 watts output counting MSW inverter loss.
Winning the lottery, panels, controllers and trackers would be nice...