A huge amount of corn goes into producing ethanol to burn as fuel in cars. We can safely take a small portion of agricultural land out of "food" production and replace it with photovoltaics and electrical production instead of using it to produce ethanol and produce productive stable returns for farmers instead of subsiding corn and fuel.
Yeah, and also you should eradicate sparrows. Each sparrows consumed several kilograms of grain per year, so by eradicating them you will need even less agricultural land.