Cost prohibitive?

It's a neat isea, also eliminates most pest problems, but putting on a diving suit to swim down to a hot little dome sounds like a nightmare. Also how do you move the crops in and out?

You could probably automate routine tending of the plants, eliminating the need for regular dives. At harvest time, you allow the domes to surface, harvest and replant, then sink them again.

At first this struck me as silly, but the more I think about it, the more sense it makes.

You could grow year round in some areas. You could rotate planting times so that there are always domes ready to be harvested.

This would open up new acreage to farming (of course you could also do that with floating barges).

Pests would be much less of a problem. If you do get an infestation, you raise the infested dome, clean it out and disinfect everything, then replant.

One question I have; how do the plants get enough sunlight? Will the amount of light that gets through the water be enough?

that's about the only real benefit I can see, otherwise you could spend less energy with a regular greenhouse, even in extreme climates, I'd think. You'd still need air ventilation, and fresh water, which could be done with some form of local desalinization, but it's starting to add up fast, not to mention the specializations you'd need from workers.

Maybe there would be enough condensation to water the plants? I'm also not sure that you'd need to ventilate.

If you google "sealed terrarium" you'll find that it's possible to have plants thrive for years, even decades, in a completely sealed airtight environment. The plants recycle the existing air and water. The only input they need is light.

To get a yield you can't just have a slow burn closed system, and you're putting it under water, so you're cutting off the sunlight. Plus the plants that thrive in that environment are specific types, there are a lot that will just fail if not treated right.

I don't think anyone is suggesting that all farming be moved underwater.

I also wonder about the sunlight, but I have to believe that they've taken something as obvious as that into account. Maybe if it's just below the surface, or the very top is just above the surface, there's enough light.

But the idea does seem farfetched.

And while they'd survive, it would be a slow growth, not pushing a crop for a season.

It sounds like solar freaking roadways. Cool idea, but the execution is lacking.

It could very well be a scam.

They deserve a refreshing drink underwater after that!

Thank you.