Imagine that you own a small, 20-acre farm in California’s Central Valley. You and your family have cultivated this land for decades, but drought, increasing costs and decreasing water availability are making each year more difficult. Now imagine that a solar-electricity developer approaches you and presents three options: You can lease the developer 10 acres of otherwise productive cropland, on which the developer will build an array of solar panels and sell electricity to the local power compa...