Well, yes, but it's not so simple. Water is free when it comes from clouds and they block the sun. So it's kind of an either-or thing. Cali's central valley get

Well, yes, but it's not so simple. Water is free when it comes from clouds and they block the sun. So it's kind of an either-or thing. Cali's central valley gets great sun but it must pipe in the water from the Sierras. That's not free. If there's a drought, well, you can't buy the water for any price. Another problem is that this cheap land with free water and sun is often a long way from the people who will eat the food. That means transportation and that also means you're still paying something even if the land, water and sun are free. Another interesting feature is the way that solar cells can capture the energy from a broad spectrum of the sunlight and then the LEDs can be tuned to the narrow spectrum that the plants absorb. Even with losses to resistance and conversion, you could end up ahead eventually.