Nevada desert landscape. Image credit:Andrew Faridian’s Geography Blog
Fresno Bee points out that "Water is the cooling agent for what traditionally has been the most cost-efficient type of large-scale solar plants." There are more expensive, air-cooled versions of the big-tower, concentrated solar power (CSP) plants; but it's the less expensive, water-sucking versions that currently are being built on public lands - in the desert - where water shortages are real.
"It is not in the public interest for BLM to approve plans of development for water-cooled solar energy projects in the arid basins of southern Nevada, some of which are already over-appropriated," Jon Jarvis, director of the Park Service's Pacific West Region, wrote to the BLM director in Nevada... Water is among the complications in deserts where more than 150 solar applications have been submitted for hot spots in Nevada, California, and Arizona, plus a few in New Mexico.
To be fair, nuclear and coal-fired plants have the identical issue and designers of any thermally powered plant have added reason to avoid the costly air-cooled versions in a cash-strapped economy.
This is where photovoltaics have the advantage: tight money and drought.
Photovoltaic systems use conducting material to convert sunlight directly to electricity and need only nominal amounts of water to wash their solar panels, compared with the traditional steam-turbine solar that uses much larger volumes of water for cooling towers.
More posts on thermal power plant water consumption.
Could Drought Kill Israel's Electric Car?
Nuclear Power's Climate Protection : Water-Use Tradeoff
Thirsty Nukes Can't Take the Heat