Compared to farming, this system uses a lot less water (which is basically free right now) and a lot more electricity (which is more expensive). So you can just

Compared to farming, this system uses a lot less water (which is basically free right now) and a lot more electricity (which is more expensive). So you can just imagine it being viable if the cost of those utilities reverses. Could happen if for example we get efficient solar power and the negative projections of fresh water availability come true.