Ask HN: What's happening in agricultural technology?

Not sure if there are any experts here, but if there are, I'm quite curious about the following:

1. Do we have any technology (independent of cost) existing today to have a fully automated farm? Meaning, set everything up and it'll just spit out yield? This would include taking into account weather, planting, removing weeds, etc. The input into this "system" of course would be the "ingredients" such as soil, soil, and of course, sunlight. [1]

2. What's the maximum yield we can get out of an acre these days? If I wanted to buy, say, an acre (for food) and start a small town in southern United States and feed 1000 people easily, is that possible? For simplicity let's say everyone is vegan.

[1] Here's a snippet of research I've done that may be of interest to readers.

Air and soil: There's been some advancements in sensors which is an obvious requisite towards the auto-farm. However I haven't read anything recently about this. Most recent was (http://gizmodo.com/swarms-of-soil-sensors-may-help-farmers-w...)

Robotics: I know they (farm bots) exist (http://modernfarmer.com/2013/08/5-robots-on-the-farm/), but I haven't heard of them actually being more productive than existing high-yield solutions. I do think in the end they'll be superior.

The single most advanced modern farm I've heard of is: http://seedstock.com/2013/01/24/indoor-grower/. Anyone know of anything that surpasses this? Just making farming (perhaps one of the most labor intensive things you can do these days) less of a burden will prove to be a game changer (e.g. you may find a single person willing and able to maintain an entire one acre farm).

I don't know what the maximum number of people you could sustain on an acre is, but my guess is way less than 1000. Like an order of magnitude less, perhaps closer to two orders less.

The world record corn yield is 500 bu/ac. 1 bushel of corn is about 1500 calories. EDIT: 1500*56=84,000 calories

If you could do 1000 people per acre, you would have enough food for 36 billion people from the state of Iowa.

A bushel of corn weighs 56 pounds (shelled) or 70 pounds (still on the ear). Using the shelled bushel in this case, 1 pound of corn = 1,656 calories so each bushel is roughly 92,000 calories. With the record yield of 500 bushels/acre that can feed 60+ people for a year!

I can't think of anything else that can come close to that kind of yield. No wonder corn syrup is in everything...

Really? I thought aquaponics and other advanced techniques drastically increased that by an order of magnitude. Doing a quick search, it seems that you're right. For an average person, with an average diet, to feed a SINGLE person you need an acre (with traditional farming techniques)[1]. Wow. I doubted a thousand people could realistically be fed on an acre, but I thought at least 10 would be trivial, and 100 possible with some efficient tech. Pretty eye opening, honestly (humbling moment, hah)

[1] http://www.farmlandlp.com/2012/01/one-acre-feeds-a-person/

EDIT:

The best I could find in terms of output in the US a farm that does about 40 tons with three acres, which is supposedly ~200 people [2]

[2] https://www.splendidtable.org/story/how-to-feed-10000-people...

I think you're making an error there somewhere, possibly mixing calorie yields per year with human requirements per day.

Divide that by 365 for a more realistic estimate. About 60 people per acre if you can maintain the world record yield, or about 15 with the mean US yield.