Minnesota · 2023
Hoot Lake Solar
Thermal mass floor heat for the operations and maintenance building at Otter Tail Power’s first utility-scale solar project.
- Owner
- Otter Tail Power Company
- Building
- 50 × 100 ft operations and maintenance building
- Panels
- 119 panels at 277 volts
- Installed with
- Otter Electric

The project
Hoot Lake Solar is Otter Tail Power Company’s first utility-scale solar project and Minnesota’s third-largest solar generation facility. Its 130,000 solar panels produce enough renewable energy for roughly 9,000 homes. It sits on the site of a retired power plant, which let it connect to existing transmission lines.
The system
Premier Energy USA and Otter Electric installed ThermaRay thermal mass floor heating in the site’s 50 × 100 foot operations and maintenance building. 119 panels at 277 volts were laid out before the sand and concrete were placed over them.
From the project story on premierenergyusa.com. Read the original post



Watch the project.
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Brooklyn Park, Minnesota A 100,000+ square foot manufacturing, warehouse and office building heated by thermal mass panels under the concrete. Compared with the engineering estimate for other systems, it has saved about $500,000 on heating.
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