Sun Prairie Library Opens a New Chapter in Energy Efficiency

When the City of Sun Prairie began planning a new library, officials looked at the problems of the aging building. The heating and cooling systems were outdated, operating costs were rising, and the library needed more space. The City wanted to manage costs while also reducing the building's impact on the environment.  

A main goal was to include sustainable features that support the City's 2035 Vision. This vision calls for Sun Prairie to become greener community that uses more renewable energy. The project also supports the City's Climate Action Plan, which aims to cut emissions by 63% by 2035 and reach net-zero carbon emissions by 2050.  

The building was also designed to become the City's first Community Resiliency Center (CRC). During an emergency, the CRC can provide heating, cooling, and backup power for the community.  

Through FOCUS ON ENERGY®, the City received an Energy Design Assistance (EDA) analysis of the entire building. This study helped the project team compare energy efficiency options and estimate long-term operating costs.  

The new library includes a geothermal system for heating and cooling. It also has solar panels and batteries that store energy. These systems work with Sun Prairie Utilities to manage energy use, make the most of power produced on-site, and help the building operate during an emergency. If the power goes out, the batteries can provide stored energy to support building operations.  

The all-electric facility was completed in March 2026. According to the EDA analysis, it is expected to reduce yearly energy costs by 39% compared to the program’s standard building design. 

Improved lighting gives visitors a brighter and more welcoming space while helping Sun Prairie meet its energy-saving goals. The new floor plan improves room layouts, traffic flow, and the use of space.

The project added 25,000 square feet, nearly doubling library’s size. The updated 60,500-square-foot facility includes separate areas for children and teens, an outdoor amphitheater, a bookstore and café, and an atrium connecting the original building to the addition.  

"Focus on Energy stayed involved through regular meetings during the planning and design process," said Svetha Hetzler, Director of the Sun Prairie Public Library. "Our Energy Advisors kept us informed about available incentives that helped reduce project costs. We look forward to seeing the long-term benefits of improved energy performance in this renovated and expanded facility."

More information about the Sun Prairie Public Library’s Expansion and Renovation can be found here along with Geothermal Objectives and Value and Microgrid Objectives and Value.