In part because traditional farms scale better than aeroponics or hydroponics. In part because farms don’t pay for the environmental damage they cause. Because of these two points, there is little incentive to industrialize aeroponics or hydroponics.

What is true right now is that traditional farms use more water, fertilizer, and space, cause more environmental damage, but require less labor. And the labor problem can be mitigated with robotics, if we’re willing to invest in that.

With an adverse event rate of 0.06%. Meaning only 33 per million people required hospitalization.

The device you’re thinking of might be a peltier or thermoelectric cooler (TEC). But yes. They’re way less efficient than a vapor compression refrigerator, though.

Oh man, been doing that for 10 years!