The combined Viridon and Blackstone team has spearheaded the development, construction, and operation of a $23 billion portfolio of transmission projects to integrate 21,000 MW of renewable energy.
california Projects
In California, Viridon is developing major new transmission projects to support the state’s ambitious climate goals while enhancing reliability.
Location: California (CAISO region)
Details: Combined 416 miles of single-circuit 500 kV transmission line and the New Humboldt 500/115kV substation.
Background: CalGrid, a Viridon subsidiary, was selected by CAISO in 2025 to finance, construct, own, operate, and maintain two transmission projects in Northern California: New Humboldt–Collinsville and New Humboldt–Fern Road. Currently under development and planned for completion in 2034, the Humboldt projects will enhance the state’s high-voltage transmission backbone, improving regional reliability while facilitating the integration of renewable energy.
Location: California (CAISO region)
Details: 84-mile, single-circuit 500 kV transmission line.
Background: Viridon acquired the Path 15 Project, which links Northern and Southern California and is a vital component of the state’s energy infrastructure. It was developed through a unique public-private partnership with the Western Area Power Administration, which owns and maintains the line. This acquisition reflects Viridon’s ongoing commitment to supporting California’s energy needs by investing collaboratively in essential infrastructure.
New york Projects
In New York, Viridon and Blackstone have a proven track record of investing in large-scale transmission infrastructure, linking offshore wind developments to New York City’s grid and advancing the state’s clean energy transition.
Location: New York (NYISO region)
Details: 100-mile, ±320kV High Voltage Direct Current (HVDC) transmission lines, converter stations, and 345kV interconnection cables
Background: This project is currently under development by Viridon New York and planned for completion in 2033. It is one of several being considered by the state to achieve New York’s ambitious clean energy goals. The project will interconnect with future offshore wind projects and deliver their energy to the Downstate grid via submarine cables, enabling the controlled delivery of 5,600 MW of local renewable power into the New York Metro area.
Location: New York (NYISO region)
Details: 339-mile, ±400kV High Voltage Direct Current (HVDC) transmission line and converter station
Background: This project is currently under construction and scheduled for completion in 2026. It is owned and managed, and was originated and developed, by Transmission Developers, a fellow Blackstone portfolio company. The project will extend underwater and underground from Quebec to New York City, enabling the controlled delivery of 1,250 MW of low-cost renewable power into the New York Metro area, while making substantial investments in environmental protection programs and other community initiatives.
Prior Projects
Lone Star Transmission
Texas (ERCOT region)
350-mile, double-circuit 345kV transmission line and 11 high-voltage stations
Completed in 2013 as part of a statewide buildout of the high voltage grid to accommodate the integration of 10,000 MW of wind energy. Current Viridon team members, while at NextEra Energy, provided oversight and support at all stages of the project, from permitting through to financing, construction, and operations.
Completed in 2013 as part of a statewide buildout of the high voltage grid to accommodate the integration of 10,000 MW of wind energy. Current Viridon team members, while at NextEra Energy, provided oversight and support at all stages of the project, from permitting through to financing, construction, and operations.
East West Tie Line
Ontario, Canada (IESO region)
280-mile, double-circuit 230kV transmission line
Completed in 2022, this project enabled the replacement of inefficient generation in Northwestern Ontario with cleaner and cheaper sources of power while enhancing reliability. The project consortium included both a Canadian energy company and pension fund, together with First Nation communities along the route. Current Viridon team members, while at NextEra Energy, led the initial development and provided oversight and support at all stages of the project.
Completed in 2022, this project enabled the replacement of inefficient generation in Northwestern Ontario with cleaner and cheaper sources of power while enhancing reliability. The project consortium included both a Canadian energy company and pension fund, together with First Nation communities along the route. Current Viridon team members, while at NextEra Energy, led the initial development and provided oversight and support at all stages of the project.
Empire State Line
New York (NYSIO region)
20-mile, single-circuit 345kV transmission line with two 345kV switchyards and a Phase Angle Regulator (PAR)
Completed in 2022, this project unlocked 3,700 MW of renewable energy from Niagara Falls and Canada for delivery throughout New York. Originally selected by NYISO in 2017 as the first competitive project in New York awarded pursuant to FERC Order 1000. Current Viridon team members, while at NextEra Energy, provided oversight and support at all stages of the project.
Completed in 2022, this project unlocked 3,700 MW of renewable energy from Niagara Falls and Canada for delivery throughout New York. Originally selected by NYISO in 2017 as the first competitive project in New York awarded pursuant to FERC Order 1000. Current Viridon team members, while at NextEra Energy, provided oversight and support at all stages of the project.
Suncrest SVC
California (CAISO region)
230kV 300 MVar Static VAR Compensation (SVC) station
Completed in 2020, this project supports the grid in and around San Diego by injecting or absorbing reactive power to maintain voltage levels, which helps integrate renewable energy. Originally selected by CAISO in 2015 as the first competitive project in California awarded to a non-incumbent utility pursuant to FERC Order 1000. Current Viridon team members, while at NextEra Energy, provided oversight and support at all stages of the project.
Completed in 2020, this project supports the grid in and around San Diego by injecting or absorbing reactive power to maintain voltage levels, which helps integrate renewable energy. Originally selected by CAISO in 2015 as the first competitive project in California awarded to a non-incumbent utility pursuant to FERC Order 1000. Current Viridon team members, while at NextEra Energy, provided oversight and support at all stages of the project.
Gridliance West
Nevada (CAISO region)
167-mile, 230kV transmission system with pending 500kV upgrades
GridLiance, a predecessor Blackstone portfolio company, partnered with a local cooperative utility in Nevada to acquire and upgrade their high voltage system. Members of Viridon’s board, and current Viridon team members while at NextEra Energy, led these efforts from inception in 2016 until the recent approval by CAISO of 500kV system upgrades to further increase the access of Nevada’s abundant solar resources to the California market.
GridLiance, a predecessor Blackstone portfolio company, partnered with a local cooperative utility in Nevada to acquire and upgrade their high voltage system. Members of Viridon’s board, and current Viridon team members while at NextEra Energy, led these efforts from inception in 2016 until the recent approval by CAISO of 500kV system upgrades to further increase the access of Nevada’s abundant solar resources to the California market.
Trans Bay Cable
California (CAISO region)
53-mile, ±200kV High Voltage Direct Current (HVDC) transmission line and two converter stations
Completed in 2010, this first-of-its-kind submarine project can deliver 400 MW from the East Bay to San Francisco, meeting 40% of the city’s peak electrical power needs while reducing energy costs and environmental impacts for California customers. Current Viridon team members, while at NextEra Energy, led the acquisition of the project in 2019 and provided oversight and support to the ongoing operations, maintenance, and management of the project.
Completed in 2010, this first-of-its-kind submarine project can deliver 400 MW from the East Bay to San Francisco, meeting 40% of the city’s peak electrical power needs while reducing energy costs and environmental impacts for California customers. Current Viridon team members, while at NextEra Energy, led the acquisition of the project in 2019 and provided oversight and support to the ongoing operations, maintenance, and management of the project.
East West Tie Line
Ontario, Canada (IESO region)
280-mile, double-circuit 230kV transmission line
Completed in 2022, this project enabled the replacement of inefficient generation in Northwestern Ontario with cleaner and cheaper sources of power while enhancing reliability. The project consortium included both a Canadian energy company and pension fund, together with First Nation communities along the route, and involved extensive environmental consultation. Current Viridon team members, while at NextEra Energy, led the initial development and provided oversight and support at all stages of the project.
Completed in 2022, this project enabled the replacement of inefficient generation in Northwestern Ontario with cleaner and cheaper sources of power while enhancing reliability. The project consortium included both a Canadian energy company and pension fund, together with First Nation communities along the route, and involved extensive environmental consultation. Current Viridon team members, while at NextEra Energy, led the initial development and provided oversight and support at all stages of the project.
Gridliance West
Nevada (CAISO region)
167-mile, 230kV transmission system with pending 500kV upgrades
GridLiance, a predecessor Blackstone portfolio company, partnered with a local cooperative utility in Nevada to acquire and upgrade their high voltage system. Members of Viridon’s board, and current Viridon team members while at NextEra Energy, led these efforts from inception in 2016 until the recent approval by CAISO of 500kV system upgrades to further increase the access of Nevada’s abundant solar resources to the California market.
GridLiance, a predecessor Blackstone portfolio company, partnered with a local cooperative utility in Nevada to acquire and upgrade their high voltage system. Members of Viridon’s board, and current Viridon team members while at NextEra Energy, led these efforts from inception in 2016 until the recent approval by CAISO of 500kV system upgrades to further increase the access of Nevada’s abundant solar resources to the California market.
Suncrest SVC
California (CAISO region)
230kV 300 MVar Static VAR Compensation (SVC) station
Completed in 2020, this project supports the grid in and around San Diego by injecting or absorbing reactive power to maintain voltage levels, which helps integrate renewable energy. Originally selected by CAISO in 2015 as the first competitive project in California awarded to a non-incumbent utility pursuant to FERC Order 1000. Current Viridon team members, while at NextEra Energy, provided oversight and support at all stages of the project.
Completed in 2020, this project supports the grid in and around San Diego by injecting or absorbing reactive power to maintain voltage levels, which helps integrate renewable energy. Originally selected by CAISO in 2015 as the first competitive project in California awarded to a non-incumbent utility pursuant to FERC Order 1000. Current Viridon team members, while at NextEra Energy, provided oversight and support at all stages of the project.
Empire State Line
New York (NYSIO region)
20-mile, single-circuit 345kV transmission line with two 345kV switchyards and a Phase Angle Regulator (PAR)
Completed in 2022, this project unlocked 3,700 MW of renewable energy from Niagara Falls and Canada for delivery throughout New York. Originally selected by NYISO in 2017 as the first competitive project in New York awarded pursuant to FERC Order 1000. Current Viridon team members, while at NextEra Energy, provided oversight and support at all stages of the project.
Completed in 2022, this project unlocked 3,700 MW of renewable energy from Niagara Falls and Canada for delivery throughout New York. Originally selected by NYISO in 2017 as the first competitive project in New York awarded pursuant to FERC Order 1000. Current Viridon team members, while at NextEra Energy, provided oversight and support at all stages of the project.
Lone Star Transmission
Texas (ERCOT region)
350-mile, 345kV double-circuit transmission line and 11 high-voltage stations
Completed in 2013 as part of a statewide buildout of the high voltage grid to accommodate the integration of 10,000 MW of wind energy. Current Viridon team members, while at NextEra Energy, provided oversight and support at all stages of the project, from permitting through to financing, construction, and operations.
Completed in 2013 as part of a statewide buildout of the high voltage grid to accommodate the integration of 10,000 MW of wind energy. Current Viridon team members, while at NextEra Energy, provided oversight and support at all stages of the project, from permitting through to financing, construction, and operations.
Trans Bay Cable
California (CAISO region)
53-mile, ±200kV High Voltage Direct Current (HVDC) transmission line and two converter stations
Completed in 2010, this first-of-its-kind submarine project can deliver 400 MW from the East Bay to San Francisco, meeting 40% of the city’s peak electrical power needs while reducing energy costs and environmental impacts for California customers. Current Viridon team members, while at NextEra Energy, led the acquisition of the project in 2019 and provided oversight and support to the ongoing operations, maintenance, and management of the project.
Completed in 2010, this first-of-its-kind submarine project can deliver 400 MW from the East Bay to San Francisco, meeting 40% of the city’s peak electrical power needs while reducing energy costs and environmental impacts for California customers. Current Viridon team members, while at NextEra Energy, led the acquisition of the project in 2019 and provided oversight and support to the ongoing operations, maintenance, and management of the project.