In Kings and Fresno counties in California, where water is severely rationed and soils are soured by years of Delta irrigation, farmers are hoping to reuse fallow land to “grow” fields of solar panels.

The land in question, all 30,000 acres of it, lies in the sunny western and southern portions of the San Joaquin Valley, where water wars, reduced water allocations from the Sacramento/San Joaquin Delta, and decades of irrigation have resulted in salt-laden soils that threaten to turn the Valley into a modern-day Mesopotamia.

Called the Westlands Solar Park, the proposed solar installations (a joint venture between Westlands Water District and privately-owned Westside Holdings) promise 5,000 megawatts of clean, renewable solar power.

This is enough to power almost 4 million homes, or slightly more than the population of Los Angeles, America’s second-largest city. And, while still not as large as the proposed African solar venture, which could power all of Europe from 100 gigawatts in the Saharan Desert by 2050, it’s a huge undertaking, and bigger than anything in existence by a factor of 100. The nearest completed project, in size, would be the 60-megawatt Olmedilla array in Spain, completed in 2008.

For Valley farmers, it is a turning away from their historic reliance on agriculture, which gave Americans a bountiful supply of tomatoes, wheat, rice, beans, alfalfa and cotton (and, more recently, stevia and blueberries).

Fortunately, all of these crops can be (and are) grown elsewhere, in areas where solar insolation isn’t quite so intense or so valuable, at least in terms of solar energy, and the proposal has created an interesting but not altogether surprising alliance between area farmers and environmental groups like the Sierra Club, which sees a crop of solar panels as kinder to California’s dwindling water supplies – and burgeoning energy needs – than almost any other solution presented.

More important, because the project will be developed largely on private lands that have been heavily farmed for generations, the usual critical habitat concerns and NIMBYism will be avoided. In other words, Westlands will face none of the opposition that has delayed or scaled back Mojave Desert solar projects, including critical habitat for the desert tortoise and a reluctance to use public lands for energy production on the part of both politicians and green groups.

As both the Sierra Club and energy experts agree, Westlands’ proximity to California’s big, power-hungry cities, as well as to the state’s biggest north-south electricity transmission lines along Interstate 5 (and to substations that distribute that electricity), make it a project with all pluses.