We figure 2000 calories per day per person. Wearing one of those Fitbit calorie counters working hard we've found that to be a good number. The women tend to be around 1600 calories per day and the guys about 2600 calories a day when working hard.
I guess the weight of that 2000 calories might be 750 lbs a year but it really would depend on what foods you're prepping I guess.
Lilburner, You're about twice my size so you may need to stock 1500 lbs of food.