Spanning more than 600 acres and featuring a 20MW/50MWh battery energy storage system (BESS) component, the 100-MW Rabbitbrush Solar Facility reached completion in November 2022. Energy generated by the facility’s more than 415,000 photovoltaic modules will serve the needs of nearly 45,000 homes per year while displacing 62,000 metric tons of carbon dioxide annually.

At the project’s peak, it employed 380 local union craft laborers. Long-term site operation positions were also created upon completion. McCarthy and its partners also worked closely with the Native American Tejon Indian Tribe to ensure respect for the area and its people throughout the construction process.

Photo courtesy Mccarthy Building Cos.

Despite the project team being well-versed in BESS work, the ever-changing nature of county permit requirements posed challenges. Battery storage technology progresses on a regular basis, so fire department and county permitting requirements have to evolve to address the changes. This required McCarthy to stay up to date on frequently changing requirements, to implement requirement changes quickly and to forge close relationships with the county permitting department to aid in clarity and compliance.

Photo courtesy Mccarthy Building Cos.

During initial excavation on the site, located on rural land outside of major city limits, crews uncovered unexploded ordinances (UXOs) that had been used for training purposes by the Dept. of Defense. With safety as a first priority, the project team quarantined the area, notified authorities and engaged a third party to complete thorough ground scans across the whole project site. All UXOs were uncovered and removed within one week without impacting the schedule.

Photo courtesy Mccarthy Building Cos.

Local furry residents also caused some tweaks to project plans. When crews discovered dens of desert kit foxes with pups, construction quickly halted in the vicinity. Under the guidance of a county-approved, third-party biologist, the project team surveyed affected areas and cordoned off the dens. Clearance underneath the project’s perimeter fences was raised by 4 in. to facilitate unobstructed movement for all wildlife, including the kit foxes.

Additionally, the natural hydrology of the area was integrated into the project’s design. By designing structural elements and meticulously considering the elevation of electrical equipment, the project ensured that the water could continue its natural course, undeterred by the installation.