In 2023, LS Power Grid California (LSPGC) was selected by CAISO through a competitive solicitation to construct, own, and operate the 500/230 kV Manning Substation Project (Project). The Project will enable the advancement of renewable generation within the Westlands/San Joaquin area and address overloads on Pacific Gas & Electric’s (PG&E) 230 kV system.
The Project will include a new LSPGC 500/230 kV Manning substation and two new LSPGC 230 kV transmission lines, which will tie the existing PG&E 500 kV system in the area to the existing PG&E Tranquility Substation to enhance reliability and increase access to cost effective solar generation.
The new Manning substation will include gas insulated switchgear (GIS), two new 500/230 kV transformers and two 500 kV series capacitors banks. The two new 230 kV Manning to Tranquility transmission lines will include approximately 10 miles of overhead transmission supported by tubular steel structures.
The existing PG&E Los Banos to Midway #2 500 kV line, the Los Banos to Gates #1 500 kV line, and the Panoche to Tranquility #1 and #2 230 kV lines will be looped into the new Manning substation by PG&E. PG&E will also modify the existing series capacitors on the Gates and Midway 500 kV lines. Additionally, PG&E will reconductor the existing Manning-Tranquility 230 kV lines.