In many ways, deserts are the ideal location for utility-scale solar power plants. There's lots of sun. There's no competition with valuable farmland. And, generally speaking, there are very few neighbors to annoy. In fact, some say that a relatively small amount of desert land would be enough to power the entire world. (But one has to be careful about such claims.)

That said, there are downsides too. 

Firstly, there's an awful lot of dust. And when solar panels get covered in dust, their output gets reduced dramatically. The obvious answer is to wash the panels regularly, but here too we run into a major drawback — deserts do not tend to have an abundance of water. A team of Stanford researchers is advocating a novel solution: the partnering of agave farms and solar power plants.

Photovoltaic (PV) solar farms run on sunlight, but water is required to remove dust and dirt from the panels to ensure they operate at maximum efficiency. Water is also used to dampen the ground to prevent the buildup and spread of dust. Crops planted beneath the solar panels would capture the runoff water used for cleaning the PV panels, thus helping to optimize the land. The plants' roots would also help anchor the soil and their foliage would help reduce the ability of wind to kick up dust.
The researchers claim this approach would not just enable the recycling of water that would otherwise go to waste. Because of the stabilizing effect of plant roots on the desert sand, it would actually result in lower overall water use for the power plant as a whole. The agave plant would most likely be used for ethanol production, reducing the need for corn-based ethanol, the sustainability of which has come into question in recent years

Of course, dual-use solar farms are nothing new, having been touted as a way to reduce pressure on valuable agricultural land. Even though desert solar doesn't compete with productive farm land, there are extremely valuable desert ecosystems that deserve to be protected too. By pairing agave farming and solar, we should hopefully be able to produce more energy on less land, leaving more of the wilderness intact. 

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