California Grid Operator Revises 2021-2022 Transmission Plan Due to Increased Demand

The California Independent System Operator Corporation Board of Governors have approved modifications to two transmission projects in San Jose due to significant increases in load forecasts driven by data center growth.

The grid operator recommended changes to the scope of the Newark – Northern Receiving Station (NRS) line and Metcalf – San Jose B projects based on a modified transmission plan for the San Jose area. The two transmission lines are anticipated to commence operations in June 2028. The two transmission projects were originally approved as a part of the 2021-2022 Transmission Plan in March 2022. After approval, in March 2023, the grid operator selected LS Power Grid California LLC as the project sponsor for both.

The long-term load forecast for the San Jose area has increased from 2,100 MW in the 2021-2022 transmission plan to around 3,400 MW in the base scenario of the current 2024-2025 transmission study, and about 4,200 MW in sensitivity scenario. The increase in the number of data centers and electric vehicles are key drivers in rising electricity demand in California.

The ISO recommended several modifications for the two lines, including the conversion of the Newark – NRS line into alternating current. The significant projected load growth in the area means that the initial HVDC converters and lines will be insufficient and a more robust, AC-based line is necessary.

For the Metcalf – San Jose B HVDC project, the grid operator recommended increasing the power injection at San Jose to 1,000 megawatts (MW) from 500 MW and increasing the voltage at the AC side of the San Jose B converter station to 230 kilovolts (kV) from 115 kV.

In the 2023-2024 transmission plan, approved by the board in May, the ISO identified the need for 26 transmission projects which would require a total infrastructure investment of over $6 billion. The plan also outlined that California requires more than 85 GW of additional transmission capacity by 2035 to meet decarbonization objectives such as increased zero-emission vehicles and building electrification.