The California Energy Commission is set to approve the Palen Concentrated Solar Power (CSP) project.

The energy commission issued a preliminary approval late Friday afternoon for the first of Palen’s two 250-megawatt Concentrated Solar Power (CSP) towers, which will be located 60 miles east of Indio. The project’s Concentrated Solar Power (CSP) developers, BrightSource Energy and Abengoa Solar, will be able to request commission approval for the second tower later on.

The preliminary decision — which was written by the two commissioners overseeing Palen’s review process, Karen Douglas and David Hochschild — is not final, but it is unlikely to be overturned by the full commission. The state agency will hold a conference Oct. 6 at UC Riverside’s Palm Desert campus to discuss Palen — part of a 30-day public comment period — before making a final decision Oct. 29.

The energy commission said in a statement that the concentrated solar thermal power plant is expected to employ about 600 people during construction, with a peak workforce of 1,200. Construction should last a little more than two years.

Palen’s approval bodes well for the future of concentrated solar power technology, which uses thousands of mirrors to direct sunlight at massive solar towers. Only one other large-scale CSP development — BrightSource’s 377-megawatt Ivanpah project in San Bernardino County — has come online in the United States, and it has been attacked by environmental groups for killing untold numbers of birds attempting to fly through the intense radiation directed toward its solar towers.

But now that the energy commission has signaled its intent to approve Palen, other developers might take a greater interest in concentrated solar power. BrightSource had asked the Bureau of Land Management to put the application for its 540-megawatt Sonoran West CSP project on hold pending the resolution of Palen’s review process. If the energy commission finalizes Palen’s approval, the review process for Sonoran West is likely to begin soon after.

The commission acknowledged in its preliminary decision Friday that the project will cause "significant unmitigated impacts to biological, cultural, and visual resources," but it argues that the project’s benefits outweigh those costs.

Palen was originally proposed by Solar Millennium, which planned to use solar trough technology. But after Solar Millennium went bankrupt, the project was picked up by BrightSource and Abengoa, which asked the energy commission to approve a concentrated solar power facility instead.

BrightSource and Abengoa originally asked to build two 750-foot solar towers, each one surrounded by 85,000 mirrors. But after the commission issued a preliminary denial of that proposal in December, the developers asked for time to amend their proposal, a request the commission granted in January.

Earlier this year, the developers altered their proposal, saying they would only move forward with the second tower if they can build it with the capacity to store solar thermal energy — and only then upon the commission’s approval. Developing storage capability is a top priority across the solar industry, due to the intermittent nature of solar power and the problems this can pose for integrating solar power into the energy grid.

That altered proposal was enough to sway the energy commission’s staff, which dropped its opposition to the project earlier this summer — even in the absence of new measures to mitigate its environmental and cultural impacts. Staff also reasoned that delaying the second tower would cut the facility’s immediate environmental impacts in half, while giving BrightSource and Abengoa the ability to test mitigation strategies at the first tower.