Agriculture Is Solar-Powered

I have posted on hydroponic lettuce growing.  If you believe the advocates of organic agriculture, commercial agriculture is essentially hydroponic, in that the soil is exhausted so the plants are growing using the nutrients supplied by chemical fertilizers.  That's an exaggeration, but there's a bit of truth in it. That bit of truth means the salient fact about commercial agriculture is: it's solar-powered.

I wonder if anyone has done the calculation of the energy required to grow the crops we raise in the U.S.?  If they have, then you could do a graphic showing the sources of all the energy required to maintain our economy, presumably with solar power being a significant contributor.

Being optimistic about the power of search engines, I tried to answer the question in the previous paragraph, which didn't give an exact answer but did lead to an interesting Harpers article including this:

Nonetheless, more than two thirds of humanity's cut of primary productivity results from agriculture, two thirds of which in turn consists of three plants: rice, wheat, and corn.