Testing Solar Thermal Generation in an Albertan City’s Power Gird
To increase and demonstrate support for renewable energy, the City of Medicine Hat tested a solar steam generator that was connected to a nearby power plant and helped power the electric turbine generators. The project was approved for funding in Round 1: Open Call in 2010. While the project faced significant challenges, this demonstration helped identify some of the gaps in how solar thermal generation functions in the region, and cold climates in general.
The Concentrating Solar Thermal Demonstration (CSTD) Project was completed in 2016 and utilized eight rows of large, curved steel panels that reflected the sun’s rays to heat oil inside a metal tube. The oil then created steam, turning a turbine at the nearby power plant, resulting in an Integrated Solar Combined Cycle plant. This technology was the first of its kind in Alberta, making this a highly innovative project. To help reduce greenhouse gas (GHG) emissions in a variety of industrial applications in Alberta, the project aimed to adapt and improve the technology for the local climate. Greenhouse gas reduction was accomplished by decreasing the fuel burned by the power plant while maintaining the same production. The project achieved a 600-tonne CO2 offset per year and exceeded initial power output goals.
Understanding Solar Thermal Technology in Alberta
The project proved it is possible to integrate and operate an Integrated Solar Combined Cycle plant in Alberta’s climate, but challenges remain. The peak power output exceeded project goals; however, CO2 reductions did not meet objectives. The analysis of the project revealed the contributing factors of this shortcoming include tracking, alignment, tuning, and cleanliness issues. The project struggled to balance the cost of cleaning compared to energy produced. Additionally, the project faced challenges related to commercial viability. This can be attributed to consolidation within the solar industry at the time the project was funded, resulting in several critical component manufacturers no longer in business. Consequently, sourcing replacement parts to reliably operate the project was difficult. Overall, despite these challenges, the solar project helped frame the City of Medicine Hat as an innovator and an active participant in the green and alternative energy industries.
What’s next?
While the project did highlight the possibility of an Integrated Solar Combined Cycle plant in Alberta, Medicine Hat has since closed the solar combined cycle plant. This is likely due to the costs of cleaning and maintenance compared to the energy output, as well as the lack of commercial viability. The project equipment remains decommissioned, with eventual repurpose of equipment and/or the site location as a preferred option. The City of Medicine Hat is still exploring future opportunities in renewable energy. Additionally, these learnings can help make any future investments in solar thermal in the province avoid potential challenges and be more likely to be successful.