The 132MW Claresholm solar farm is located in Willow Creek district in southern Alberta, Canada. Credit: Capstone Infrastructure.
The Claresholm solar farm is installed with approximately 477,198 photovoltaic solar panels. Credit: only_kim from Shutterstock.
The solar project is backed by a power purchase agreement with TC Energy. Credit: ESOlex from Shutterstock.

The 132MW Claresholm solar farm is located 13km southeast of Claresholm town in the municipal district of Willow Creek in southern Alberta, Canada. Developed by Claresholm Solar, it is the country’s largest operating solar power plant.

Claresholm Solar is a joint venture between Capstone Infrastructure, a renewable energy investment company based in Canada, and Obton, a Danish investment company involved in the development of solar and wind power projects. Capstone Infrastructure acquired the majority 51% stake in the project from the project’s initial developer Perimeter Solar in January 2020. Obton owns the remaining 49% stake.

The Alberta Utilities Commission (AUC) approved the C$200m ($162.76m) development of the project in 2019. Construction of the solar farm began in November 2020 and commercial operations started in April 2021.

The project generated more than 350 full-time jobs in Alberta during the construction period and employed more than 650 skilled workers at the site during the peak phase. The solar farm is expected to contribute property tax revenue of C$35m ($28.21m) to the local economy over the project life.

The Claresholm power plant is projected to help avoid approximately 149,000 metric tonnes of CO₂ a year and generate sufficient renewable power for approximately 33,000 households in Alberta.

Claresholm solar plant make-up

Located on 1,280 acres of agricultural land, the project comprises approximately 477,198 photovoltaic solar panels, mounted on fixed-tilt racking with a total capacity of 132MW. The infrastructure also includes the Granum 604S substation, collector lines, electrical inverter stations and an associated building for operations, maintenance and control.

The Granum 604S Substation contains a 138/34.5kV, 90/120/150-megavolt ampere transformer, nine 34.5kV circuit breakers, a 138kV circuit breaker, a chain-link fence and other associated substation components.

Energy off-take agreement

Electricity generated from the solar farm will be sold to Canada’s TC Energy under an eight-year power purchase agreement (PPA) to supply 74.25MW. The remaining power will be sold in the wholesale power pool of Alberta.

Transmission details

The AUC-regulated Alberta Electric System Operator (AESO) connected the Claresholm solar farm to the Alberta Interconnected Electric System in Claresholm through a 138kV transmission line, which connected the plant to Altalink’s existing 138kV transmission line 180L in the area.

Altalink, the transmission facility owner in Claresholm, is responsible for detailed siting and routing, construction, operation and maintenance of the transmission facilities.

Financing for Claresholm Solar Project

Claresholm Solar secured funding worth up to C$115m ($79.99m) from ATB Financial, Fiera Infrastructure Private Debt Fund and Telus Pensions Liability Hedging Master Trust for the construction of the project under a credit agreement signed in July 2020.

Claresholm committed C$129,036 ($93,674) for the execution of material project contracts for the construction of the facility in 2020. Capstone funded its share of the project cost through its liquidity and the revolving credit facility of its subsidiary Capstone Power.

Contractors involved

Canadian firm PCL Construction was contracted for the development of the solar photovoltaic project.

Photoventus, a North American renewable power engineering company, was responsible for the engineering works of the project.

Capstone’s renewable energy portfolio

Capstone Infrastructure operates more than 750MW of installed capacity across 29 facilities in Canada. Its solar energy portfolio comprises two solar projects – the 20MW Amherstburg solar park in Ontario and the recently commissioned Claresholm solar plant. The company’s portfolio also includes wind, hydro, biomass and natural gas co-generation power plants.

Capstone’s facilities together generate more than 1,400GW hours of electricity, which can power more than 1.5 million households in Canada a year.