> They are climate controlled environments where light is provided via grow lights
Solar's efficiency is below 50% [https://www.nrel.gov/pv/cell-efficiency.html]. Considering that, I'd guess for each m² of solar panel deployed, you'll get <50% of the yield that would be produced in that same land with horizontal farming (assuming fertile land).
You can argue that solar panels can be deployed in non-agricultural surfaces, and that's true, that allows to grow things where it was not possible before. But I'm not convinced that vertical farming is more efficient than horizontal on very important metrics like cost and GHG emissions
Solar's efficiency is below 50% [https://www.nrel.gov/pv/cell-efficiency.html]. Considering that, I'd guess for each m² of solar panel deployed, you'll get <50% of the yield that would be produced in that same land with horizontal farming (assuming fertile land).
You can argue that solar panels can be deployed in non-agricultural surfaces, and that's true, that allows to grow things where it was not possible before. But I'm not convinced that vertical farming is more efficient than horizontal on very important metrics like cost and GHG emissions