RE Papago LLC on May 7 filed with the Arizona Power Plant and Transmission Line Siting Committee an application for a certificate of environmental compatibility for construction of the RE Papago Solar Gen-tie Project, which involves a proposed substation and associated 500-kV transmission gen-tie line in western Maricopa County, Ariz.
The estimated $20.4m project is needed to connect with RE Papago’s solar photovoltaic (PV) electricity generating and energy storage facility that would be built in the vicinity. RE Papago added that the project would transmit the electricity generated from the solar facility to the nearby existing Delaney substation, which is owned and operated by Arizona Public Service (APS), and ultimately to the regional electric grid.
The project is located south of Interstate-10 and is about 5.5 miles west of the community of Tonopah, Ariz.
RE Papago added that the approximately 0.3-mile gen-tie line would consist of metal transmission towers, conductors, insulators, optical fiber cables, and safety equipment. The gen-tie line would be supported by up to four high-voltage support structures consisting of a combination of A-frame dead-end structures and either H-frame, 3-pole, or monopole structures.
RE Papago also said that the substation would be located within an area of up 13 acres, just west of the existing Delaney substation. The substation would receive electricity from consolidated intermediate voltage cables from the solar facility’s collection system and would increase the voltage up to 500 kV via one high-voltage transformer bank consisting of up to three individual transformers. The company added that the substation area would include a control building enclosure that would be used for communication purposes and contain relays and supervisory control and data acquisition equipment.
Of the solar facility, the company said that it would generate 300 MW of alternating current and up to 1,200 MWh of energy storage from the installation of PV solar arrays on about 2,800.8 acres of unincorporated, privately owned land in Maricopa County. RE Papago said that the solar facility is not part of the application for a CEC as it is not within the permitting or approval jurisdiction of the committee.
Among other things, the company said that the project was included in an area approved under a Major Comprehensive Plan Amendment (CPA) in December 2019 for the entire solar facility project, a second General CPA that was approved in January 2020, and is currently under application for a permit for a zone change with industrial overlay, which is anticipated in mid-2021. Within the zone change application, the company said, a variance request is included for Maricopa County’s requirements that structures to support electric transmission lines observe a maximum height of 120 feet. The proposed project would be compatible with all zoning ordinances of the county prior to beginning construction, RE Papago said.