Colorado's San Luis Valley, an alpine desert, is rapidly becoming a leading producer of solar energy in the United States. The sun shines more than 340 days a year in the San Luis Valley. So the solar industry is booming here.
Several solar facilities in the region generate electricity on an industrial scale and others are under construction. Under Colorado law, 30 percent of power used in the state must be generated from renewable sources by 2020. But given the demand for electricity, Alamosa County's year-round sunshine still won't be enough.
Nick Thiel, plant manager of San Luis Solar Ranch, said, “We are sitting on 220 acres [89 hectares] with roughly 110,000 panels, equivalent to a 30-megawatt site,” said Thiel.
The company says that's enough to supply power to more than 7,500 homes.
“In the mornings, when the sun rises over those mountains, their sensors attract the sun, so they move in concordance with the sun. In the morning they face the east, and as the day falls, it will follow all the way to the west until it sets,” said Thiel.
In this valley, solar farms are expanding rapidly, making Colorado the third-largest solar energy producing state in the US, after California and New Jersey.
But the sun is not enough.
Alamosa County, one of the largest in the region, has six solar farms. County Commissioner Darius Allen said 650 hectares have been allocated for solar power and more could be dedicated, if the infrastructure were better.
“Right now, the transmission lines we have in here is pretty much maxed out,” said Allen.
But that's not the only problem. San Luis Valley is an agricultural area producing potatoes, grain, alfalfa and pasture for cattle. Farmers are concerned about land going to the solar industry.
Steve Vandiver is General Manager of the Rio Grande Water Conservation District. He said, “If agriculture goes away here, we have nothing left."
Agriculture in this valley is under another threat. The land, rivers and aquifers under the Valley are drying out. That also affects solar power.
“Some of the bigger plants - the solar thermo plants - take a significant amount of water. You have to dry up a lot of farm land in order to create a water supply that is large enough to support those types of plants,” said Vandiver.
Solar panels also need to be washed because dust accumulates on them.
The water shortage has forced authorities to draw up plans that will close hundreds of wells and retire agricultural land.
“Valley wide we are probably looking at 60 to 80,000 acres [24,000 to 32,000 hectares] that will have to come out of production in the long term,” said Vandiver.
Farmers are concerned. George Whitten is his family's third generation on this organic ranch.
Recently, he and his wife Julie Sullivan, an environmental activist and educator, recruited neighbors in a bid to fight the construction of an 800-hectare solar farm adjacent to their land. They won their case, and the project failed.
“I never thought I would be fighting solar energy, and so it was very bizarre,” said Sullivan.
“It’s giant parabolic mirrors. They are the size of a drive-in theater, and there were going to be 9,000 of those right along that power line,” said Whitten.
The Whittens say industrial sites - even solar ones - should not replace agriculture.
They say instead of saving energy, Americans are trying to figure out how to use more.