+1 on Quakers comments. One family on their own stands little chance. Dont forget medical emergencies! Chopping firewood, dropping timber, working the land is a bit more hazardous in practice than many have thought. In particular to the unpracticed.
A great source of food that requires little, to no maitenance. Even provides a
great source of entertainment...
FISH. When looking for a homestead, one with an existing pond would be ideal. But man made ponds can be very good to, and not as expensive as you may think to have built and stocked. It takes research on having proper structure for bigger fish to survive, but once in place its hard to beat as a renuable resource of food and water.

Something else to consider when choosing a power supply. Solar panels break
very easily in high winds! Even if you only get one storm a year it may do thousands of dollars of damage (if replacement parts are available). The weight of ice can crack them before your even out of bed in the morning.

Wind generators are rarely sufficient by themselves, and can be seen from great distances. Also require dangerous maintenance. Priority number one to
me when considering a homestead is a strong creek that runs cleanly all year. NOT hard to find in most parts of the country either. Just stay away from rivers! To many reasons to list.

I know I posted it before, but its a
reeaaallllly good read!
http://www.backwoodshome.com/articles2/gentleman0711.html?en