ECI provided the complete design of the substation, BESS, and transmission line associated with the Pinal Central Project. The Pinal Central project is a 20 MW solar farm outside Coolidge, Arizona.
ECI’s scope of work involved the design of the “open air” solar collector substation with a 34.5-230 kV (33/44/55 MVA) main power transformer (MPT). This substation was designed to connect approximately 40 MW of solar generation to the 230 kV system. Initially, 20 MW of solar generation was connected, with provisions for 20 MW of future generation. Additionally, ECI designed a Battery Energy Storage System (BESS) to connect approximately 10 MW to the substation. The BESS is located adjacent to the Pinal Central Collector Substation, and connects via a 34.5 kV feeder to the 34.5 kV bus. Additionally, ECI designed approximately 0.4 miles of overhead 230 kV transmission line to interconnect the new substation to the existing Salt River Project (SRP) Pinal 230 kV Switchyard.