Off-grid cabin: when solar payback isn't really the point

For a remote cabin, solar isn't competing with grid electricity, it's competing with the cost of running a power line (often 30,000+ dollars per mile in the US) or a generator (1-2 dollars per kWh in fuel and maintenance). At those alternatives, even a 25,000 dollar off-grid solar + battery system pays back in year one. Sizing is different: you need 2-3x the daily kWh in battery capacity, and you size for winter (worst-case sun), not annual average.