XPrize in Food Security

The world faces important food challenges.  How do we incentivize researchers and innovators to address these challenges?  One option is through prizes.  Set a desired target outcome, and the first person (or team) to achieve the outcome wins a sizable monetary prize.  

Xprize is an organization seeking to apply this model to a variety of applications.  They are now floating the idea of a prize related to food security .  Here's the motivation 

With the growth of the world’s population, and the negative effects of climate change, the demand for food will become increasingly greater, putting our food security at risk. With nearly 70 percent of the population living in urban areas by the year 2050, the distance between food sources and consumers will lengthen, further jeopardizing our food security.

While I agree with the first sentence, I'm not sure the 2nd one makes must sense.  We've been urbanizing for a century in the US, and food security in this country (at least for most people) has generally improved.  Nonetheless, research on these issues is worthwhile.  The good news is that there are many researchers working on precisely these issues.   Here's the sketch of possible prizes:

Multiple prize concepts can be developed to help ensure food security. Depending on the prize designed, the winning team will a) produce the highest edible calorific output grown on a given piece of arid desert land using less than a TBD amount of water, fertilizer, and other inputs; b) create a “farm in a box” that provides enough caloric yield daily for a family of four using less than TBD water and other inputs, costs less than a TBD amount per year, and has a footprint of less than one square meter; or c) create a system that produces and delivers 10 crucial, predetermined micronutrients for human health in a sustainable manner at a cost less than TBD.