By 2050 the Planet population is expected to be close to 10 billion people. That’s much less than the estimated number of ants living today (1 quadrillion, that is 100,000 more than the expected 10 billion humans in 2050) but their total weight is two orders of magnitude less than the one of humans and roughly we can say that humans use 3 orders of magnitude more Earth resources than ants. The growing number of resources used just for feeding is a major issue. It has been a major issue for most part of our story on the planet, with the growth of human population often constrained by the amount of available food, technology -improvement in agriculture- has been a fundamental component in making more food available, hence sustaining more people.
Notice that to sustain the quest for food of a growing human population we inject more needs in the “planet-System”. We have now over 1 billion cattle , 23 billion chicken (the number of chicken eaten worldwide each year has reached 66 billion, over 2000 each second), an undefined number of shrimp (but the FAO estimate we eat some 300 billion shrimps each year half of them “produced” in fisheries) in the world to serve our hunger for meet. All these animals have to be fed and this multiply the demand on agriculture.
No wonder that substantial investment is dedicated to find new ways of producing food.
In the Netherlands Beladon is experimenting with self sustainable floating farms. They have one active in the port of Rotterdam, hosting 32 cows eating potato peals and grass clippings. They produce 2.5 tons of dung each day that is collected by a Roomba like robot and processed in the lower floor of the barge to be converted in fertiliser. Another robot is milking the cow, 5 gallon a day from each heifer.
Clearly, 32 cows out of 1 billion is close to nothing, but it is interesting to see how new approaches are being tested, leveraging on automation supported by better and cheaper technology.