I found the following information in our local paper, I find the figures are really uplifting, especially for countries like mine which are always in drought & have destroyed so much farming land through bad farming practices:
There are 2 systems available I'll just relate the details on the smallest one being a shed 10m x 13m roughly 30 x 40 feet; the output of which is equivalent to 300 acres of improved pasture which would cater to 150-170 cattle or 2500 sheep. (I'm a vegetarian, but I can see huge environmental benefits here)
The shed uses vertical hydroponic farming & produces a crop of feed in 7 to 8 days! Uses 650 litres of water/day as opposed to 250,000 litres when irrigating for the same harvest! It takes 1 person 4-5 hours a day of harvesting, cleaning the trays & reseeding to run the show. It cuts down on not only water & acreage, but tractor work, fuel transport, storage for grain, silage, lucerne/hay, the feed is fresh, not sprayed with chemicals & on it goes.
This technology, looks to me like it is going to change the face of farming in my country in the not too distant future.