Back in the '80s I attended a lecture by chemist Melvin Calvin. He described his project of developing a biofuel plant from a succulent, such that it would thrive in desert terrain and not overlap with farmland, as corn for ethanol does. I haven't heard about it since, so I'm guessing that it didn't work out. Even if successful it would compete for the same land as solar, but there's enough of such land for both. There is so much land that is suitable to solar but not crops that I'd think it would be rare to make sense to cover good soil with a solar farm. BLM manages a huge portfolio of non-aerable land with suitable sunlight. Yes, power infrastructure costs more from such remote areas. But places where there is enough irrigation water for crops are golden, for reducing trade deficits if not for feeding and clothing us locals.