EAGLE MOUNTAIN, Calif. _ Steve Lowe gazed into a gaping pit in the heart of the California desert, careful not to let the blistering wind send him toppling over the edge.
The pit was a bustling iron mine once, churning out ore that was shipped by rail to a nearby Kaiser Steel plant. When steel manufacturing declined, Los Angeles County tried to turn the abandoned mine into a massive landfill. Conservationists hope the area will someday become part of Joshua Tree National Park, which surrounds it on three sides.
Lowe has a radically different vision.
With backing from NextEra Energy _ the world's largest operator of solar and wind farms _ he's working to fill two mining pits with billions of gallons of water, creating a gigantic "pumped storage" plant that he says would help California get more of its power from renewable sources, and less from fossil fuels.
Lowe's project, known as Eagle Mountain, is no outlier. Across the country, companies are scrambling to build similar facilities to complement solar and wind farms.
Those plans are brushing up against concerns from environmentalists, who love solar and wind but usually oppose building new dams, a feature of many pumped storage projects. Critics have said some of the proposed facilities would flood scenic canyons, interrupt free-flowing stretches of river and harm fish and wildlife.
At Eagle Mountain, one of several abandoned mining pits would be filled with water, pumped from beneath the ground. When nearby solar farms flood the power grid with cheap electricity, Lowe's company would use that energy _ which might otherwise go to waste _ to pump water uphill, to a higher pit.
When there's not enough solar power on the grid _ after sundown, or perhaps after several days of cloudy weather _ the water would be allowed to flow back down to the lower pit by gravity, passing through an underground powerhouse and generating electricity.
"It's such a natural solution for the integration of solar," Lowe said.
The Eagle Mountain plant wouldn't interrupt any rivers or destroy a pristine landscape. But environmentalists say the $2.5-billion facility would pull too much water from the ground in one of the driest parts of California, and prolong a history of industrialization just a few miles from one of America's most visited national parks.
Lowe rejects those arguments, saying his proposal has survived round after round of environmental review and would only drain a tiny fraction of the underground aquifer.
The project's fate may hinge on a question with no easy answer: How much environmental sacrifice is acceptable _ or even necessary _ in the fight against climate change?
