I like this idea but you have to consider how much it would cost to actually construct something like this far away enough to not bother wildlife. That is plumbing, electric, etc. that needs to be out in place and if we focus on cold zones, shipment will be made harder and would likely take longer. I think downsizing farms is better. Like in the US, instead of everyone getting most of their produce from Cali, every state has farms for their own and in cold zones, you have the larger greenhouses, like you mentioned.