The Westlands Solar Park (WSP) being developed in San Joaquin Valley, California, the US is expected to be the biggest photovoltaic (PV) solar park in North America and one of the biggest such facilities in the world.

Planned to be developed in phases, the massive solar park will involve PV solar power installations for a total capacity of up to 2.7GW.

CIM Group, a real estate company based in the US, is the developer of the Westlands solar power project.

Construction on the 250MW Aquamarine solar project that represents the phase one development of the solar park was started in March 2020 with the start of operations expected in late 2021.

At full capacity, the 2.7GW Westlands solar park is expected to provide clean renewable electricity for more the 1.2 million Californian households.

Westlands solar park location and site details

The Westlands solar park is proposed to be developed on more than 20,000 acres in western Fresno and Kings Counties in the southern San Joaquin Valley, California.

The San Joaquin Valley possesses one of the highest quality solar resources in the western US.

The Westlands solar park site was identified as a Competitive Renewable Energy Zone (CREZ) in 2016, as part of the Renewable Energy Transmission Initiative (RETI) which was spearheaded by the California Energy Commission (CEC) and the California Public Utility Commission (CPUC) in order to meet the state’s greenhouse gas emissions reduction target.

Westlands solar park master plan

The WSP master plan calls for a total of 12 solar power generating facilities to be developed in a period of 12 years. The installed capacity of each solar farm within the complex is planned to be up to 250MW.

The solar park is planned to be gradually expanded with an average of 167MW of installations per year.

The PV panels of the solar park will be mounted either on horizontal tracker or fixed-tilt systems.

The direct current (DC) electricity generated by each solar array will be gathered and transferred through an underground cable system to a power conversion station (PCS) to convert into alternating current (AC).

The AC electricity from each solar block will be stepped up to a transmission voltage of 230kV at one of the substations of the solar park.

CIM completed a 2MW pilot project to study the feasibility of the large-scale Westlands solar park project in 2016. The electricity generated by the pilot project is supplied to the Anaheim Public Utility.

Power transmission from the Westlands solar park

The electricity generated by the WSP is planned to be fed into the electrical grid through two 230kV gen-tie lines connecting the existing 500kV Gates Substation in Fresno County, California.

One transmission line will originate at a planned substation in the southern portion of the solar park at Nevada Avenue and run westward along the Nevada-Jayne Avenue roadway for approximately 18.5km to connect the Gates Substation.

The second line will originate at a planned substation in the northern portion of the solar park and run south-westward along the existing 230kV Henrietta-Gates transmission line for approximately 18.5km to connect the Gates Substation.

Westlands Aquamarine solar project details

The Westlands Aquamarine solar farm being constructed as part of phase one development of the Westlands solar park will spread over 1,825 acres and include a 230kV substation.

Valley Clean Energy, a local utility that provides electricity for the California cities of Davis and Woodland as well as the Yolo County, will purchase 50MW from the Aquamarine solar farm under a 15-year power purchase agreement (PPA) starting from 2021.