It’s always possible that there’s some economic hitch in here: one that I’m not competent to divine. But they do seem to be saying that there isn’t one, that this is actually profitable, without subsidy.
So, parabolic reflectors concentrating on a heat exchanger which heats up seawater which is fed into a greenhouse where plants are grown hydroponically. There’s a bit more about cooling it as well.
If this does work then absolutely great. No soil issues, no fresh water issues. Very small (backup only) fossil fuel costs.
I have a feeling that this will only work as what I would call “truck farming” though. It’s not going to work for mass carbohydrate crops like rice, wheat or potatoes or maize. Which do, after all, still provide the majority of calories around the world. But for high value (relatively of course, this is farming and food we’re talking about) items like tomatoes, strawberries, cucumbers, peppers etc they do indeed claim that it works.
And if it really does work then there are island communities (Cabo Verde is mentioned in the piece, but there would be many more like the Caribbean ones) that should just be gagging for this.
I don’t know if it really does “work” in a proper economic sense. Perhaps one of our resident farming experts could tell us? But if it does it sounds like a damn good idea to me. There’s plenty of places around the world with shitty soil, vast amounts of sunshine and seawater close to hand.