I tried some calculations comparing the amount of work energy you can get out of an acre of solar vs an acre of corn grown for ethanol. I get different numbers depending on data sources but it's around 50 times more.
It's enough it sends my thoughts down the path of what if instead of green ammonia based fertilizer you start talking synthetic amino acids.
My nutter cousin likes to post pictures on facebook of rural solar farms that he claims are destroying the environment. And pictures of farms and cattle ranches that are natural. He lost his house rural house in a fire and now rents.
But yeah plants are 2% efficient or something and most crops require a lot of energy input. And we've got maybe 100 years of topsoil left in a lot of places.
2% is, I believe, the maximum efficiency ever recorded for conversion of sunlight to food calories. The typical yield on a farm is much lower (granted, some of that goes to non-food biomass). The yield for crops grown to produce meat, especially beef, is MUCH lower.
Fun fact: on a perfectly still day, photosynthesis of a corn field will be curtailed because the plants strip all the CO2 out of the available air, and do so remarkably quickly (IIRC in about five minutes in full sun.)
It's enough it sends my thoughts down the path of what if instead of green ammonia based fertilizer you start talking synthetic amino acids.