Washington governor delays approval of hybrid BESS proposal from Cypress Creek Renewables

Ferguson has held the position of Governor for almost nine months now, replacing Jay Inslee at the beginning of the year. Inslee served as the Head of Washington State for 12 years.

As reported by Energy-Storage.news in January 2025, Inslee approved a solar and storage project under development in Benton County in one of his final acts as Governor.

For those unfamiliar with permitting in Washington, the EFSEC provides a “one-stop” siting process for major energy projects destined for the state, coordinating all licences and evaluation steps.

Although not mandatory for renewable energy projects, the EFSEC’s approvals process provides energy storage developers with an alternative to locally administered permitting routes—similar to the California Energy Commission’s (CEC’s) opt-in certification scheme.

As part of its review process, the EFSEC works with developers and stakeholders to ensure projects adhere to local land use plans while minimising impacts on the surrounding environment.

The approvals process culminates with the EFSEC making a final recommendation on whether to approve or deny the project, with the Governor having the final say on whether to give the greenlight.

In terms of a timeline for the Carriger Solar project, Cypress Creek submitted its initial application during February 2023, with the EFSEC publishing its approval recommendation at the end of June this year.

Carriger Solar is one of five clean energy projects currently under review by EFSEC, that also includes a 200MW/800MWh standalone BESS proposal from independent power producer (IPP) Tenaska.

In his letter to the EFSEC Chair, Ferguson outlined the importance of Cypress Creek’s Carriger Solar development when considering Washington’s overall decarbonisation goals.

According to Ferguson, Washington requires an additional 24.2GW of electric generation capacity to meet the state’s 2050 electricity needs, which Carriger would contribute to.

Despite agreeing with the council’s approval recommendation, Ferguson has asked EFSEC to consult with Yakama Nation further and then resubmit the project’s Site Certification Agreement (SCA).

During the initial project review process, Yakama Nation suggested EFSEC implement several mitigation measures in order to minimise the impact to “traditional cultural properties” owned by the First Nation community.

Further details of these “cultural properties” weren’t divulged within Ferguson’s letter, “out of respect for their sensitive nature.”

As Yakama Nation “did not have an adequate opportunity to review and respond” to some of the mitigation measures proposed by EFSEC within its SCA, Ferguson has asked for the council to give the First Nation community an opportunity to provide further input.

The mitigation measures suggested by EFSEC include continued site access for Yakama Nation during construction, additional vegetative screening and also increased setbacks.

Ferguson has asked EFSEC to “give due consideration to any input received” from Yakama Nation in the creation of an updated SCA, which he expects to receive no later than October 21 2025.

Cypress Creek is targeting commercial operations for its Carriger Solar project sometime during 2027.

Approval recommendation of the Carriger Solar project wasn’t unanimous, with Klickitat County representative Matt Chiles voting against the other five EFSEC members.

In a recent open letter addressed to Governor Ferguson, Chiles explained the reasoning behind his vote, which he put down to the “consistent loud and vocal opposition to this project from what appears to be an overwhelming percentage of the local Klickitat County population,” which also includes the county’s three commissioners.

Chiles listed three aspects of the project which he attributed to the project’s opposition, with the inclusion of a BESS being one of them.

Battery storage is “not yet safe, and these systems (including the technology proposed for the Carriger project), have been shown repeatedly to melt down in catastrophic fires,” asserted the Klickitat County representative.

Instead of lithium-ion based technologies, Chiles suggested that moving forward, battery storage systems utilise “new technologies that are engineered to not overheat and catch fire” or otherwise, be placed underground in bunkers.

Ferguson addressed these points as part of his recent letter and explained that although EFSEC staff considered other commercially available battery chemistries, LFP technology offered the “best combination of commercial availability, safety margin, and longevity.”

The Washington Governor also stated that despite Chiles’ claims, the EFSEC has “adequately addressed fire-safety concerns associated with battery energy storage systems.”

Alongside the creation of an emergency response plan and continued coordination between the developer and Klickitat County Fire Protection District, EFSEC has also ordered Cypress Creek to install and maintain a 10,000 gallon water cistern at the project site in the event of a fire.