I enjoyed watching the show. Though I'd rather be on a ship equipped with technology to turn sea water into drinkable water and aquaponics, the science of growing food in water with the help of fish.
We have that technology already.. why waste time, energy and resources on a situation that may never happen.
Also, it doesn't take 1 acre of land to feed 1 person for a year. Scientists and permaculture gardening practices already feed whole communities on less than an acre of land.