Palen Concentrated Solar Power (CSP)developers BrightSource Energy and Abengoa Solar have proposed a host of changes to the project.

Palen Concentrated Solar Power (CSP) developers BrightSource Energy and Abengoa Solar have proposed a host of changes to the project, sparking a new wave of legal filings from all sides. The proposals appeared to pay off on Monday, when the energy commission’s staff withdrew its original recommendation for denial, instead declaring that it “no longer has a recommendation.”

While the commission is not obligated to follow its staff’s recommendations, the change of course was a positive development for BrightSource and Abengoa. With commission staff no longer actively opposing the project, the odds of moving forward seem better than they have been in months.

The developers hope for energy commission approval by October, believing that if they start construction any later, they might not be able to apply for federal income tax credits that expire at the end of 2016.

But environmental and tribal groups are still largely unimpressed with the mitigation methods the developers have proposed. Several dozen people testified against the project at the hearing this week, some during a grueling Wednesday session that lasted from 9 a.m. until nearly 10 p.m.

Among those testifying was Gary Cathey, chief of the aeronautics division of the state Department of Transportation. At the energy commission’s request, Cathey had flown over BrightSource’s massive Ivanpah solar plant — which uses the same concentrated solar technology that would be used at Palen — to test the glare created by the thousands of mirrors in the open San Bernardino County desert.

“Flying in the vicinity of the (Ivanpah) facility generated the brightest, most extensive amount of glare that I have seen in my aviation career — and I have been flying since 1986,” Cathey wrote in a May email to the commission. “As you may have noticed, I had to shield my eyes with my hand as I was scanning for aircraft traffic while we flew eastbound.”

However, Palen’s developers have disputed claims the glare from the Ivanpah facility creates unsafe flying conditions.

Ileene Anderson, a senior scientist with the Center for Biological Diversity, testified Wednesday on the potential for bird deaths at Palen. Intense radiation from the mirrors at other concentrated solar plants — known as solar flux — can be extremely deadly, she said, arguing that more data is needed from the Ivanpah plant before the commission can make an informed decision on Palen.

“We hope that the commission sees that the project really hasn’t changed, that the same impacts are there, that there doesn’t seem to be any solutions that the company has offered,” Anderson said in an interview Thursday.

Anderson added that the developers’ proposed methods for keeping birds away from the facility are either unproven or known not to work. Those methods, she said, include scaring birds away using loud noises and installing plastic owls.

“They’ve talked about getting dogs out there to scare birds off the site. They’ve talked about getting trained raptors to scare birds off the site,” she said. “How are those dogs going to be controlled?”

Representatives from the Colorado River Indian Tribes also testified Wednesday. In a filing with the energy commission last month, David Harper, a spokesman for the tribes’ Mohave Elders’ Committee, wrote that bird deaths at the proposed development would be “detrimental to our culture because these animals are crucial to the practice and existence of our Mohave culture and belief.”

In a separate filing, attorneys for the Colorado River Indian Tribes took issue with a proposed $2.9 million cap on the amount the developers would be required to spend to mitigate impacts to tribal lands.

“If a cap is imposed, it must adequately ensure that all mitigation can be completed within the cap,” they wrote.

The energy commission staff’s decision to drop its opposition to the project, however, did not hinge on any of the developers’ proposed mitigation methods. Rather, commission staff responded favorably to the developers’ pledge they will only build the second tower if it has 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. Even in the absence of significant new measures to mitigate Palen’s environmental and cultural impacts, storage capability could tip the energy commission in the project’s favor.

Commission 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. It would also allow researchers to continue studying bird deaths at concentrated solar facilities before the commission decides for or against a second tower.

Anderson, though, was skeptical that BrightSource and Abengoa would ever implement solar storage technology at Palen. As recently as February, the developers wrote in a filing to the energy commission that while “it is technically feasible to incorporate” thermal energy storage at Palen, “financial and policy barriers prevent the actual construction of (thermal energy storage) equipment at this time.”

“Future market, policy and regulatory conditions may evolve to increase the commercial value of (concentrated solar power) projects with thermal storage, including at a hypothetical PSEGS (Palen) project with thermal storage,” they wrote in February.

In their most recent filing on the potential for thermal storage, though, the developers say nothing about market, policy and regulatory concerns. And Roger Johnson, deputy director of the energy commission’s siting and environmental protection division, said commission staff didn’t discuss those concerns before they dropped their opposition to the project.

Anderson said the storage question fueled a great deal of discussion at the hearing Wednesday.

“They are saying that they want to build this one tower without storage now, and at some point at a later time, they will be building a second tower with storage. But they don’t know what kind of storage,” Anderson said. “It’s all up in the air, no details on that. So it’s very hard to evaluate impacts.”

Anderson speculated that the developers could renege on the promised storage capability later, building the first tower now and then asking the energy commission to approve the second tower without storage.

“We worry that if a permit is granted now as they propose below, there is no guarantee that second tower with storage would ever be built,” she said in an email.

Johnson, who submitted the letter indicating that commission staff “no longer has a recommendation” on the project, was called during the hearing to clarify his that stance. He said that under the developers’ current proposal, the commission would only approve a second tower that had storage capability.

BrightSource spokeswoman Jennifer Rigney declined to comment on the hearings, except to point to statement in the developers’ filings with the energy commission.

Anderson said that energy commission members didn’t provide any clues Wednesday as to how they might decide.