The City of Woodbury is quickly becoming one of the more energy efficient communities in the Twin Cities Metro area. Having already completed recommissioning studies and lighting retrofits in a majority of its city buildings, Woodbury took another major step toward energy efficiency with the renovation of Bielenberg Sports Ice Arena refrigeration system.
In 2009, the city received an Energy Efficiency and Conservation Block Grant (EECBG) through the U.S. Department of Energy as part of the American Recovery and Reinvestment Act (ARRA), which provided an excellent impetus to start the project. The purpose of the EECBG program was to create or retain jobs, reduce greenhouse gas emissions, and reduce energy use.
The EECBG funding came at a perfect time for Woodbury. According to project manager and Woodbury Parks and Recreation Director Bob Klatt, the Bielenberg Ice Arena was already 15 years old and in great need of an energy efficiency upgrade. The funding, matched with utility rebates and expected energy savings, made the project cost-effective.
The primary goal of the project was to replace the existing ice arena refrigeration system with an energy-efficient geoexchange system. A geoexchange system, also known as ground source heat exchange, is an electrically-powered heating and cooling mechanism designed specifically for indoor spaces. The system improves efficiency by using the earth as both a heat source and a heat exchange.
Standard refrigeration systems work by extracting heat energy from outdoor air in winter and by transferring heat to outdoor air in summer. This becomes problematic with extreme temperatures in both seasons. The colder the outdoor air in the winter, the harder it is to extract heat, and in the summer when the air is hotter, it is harder to transfer heat to it. This issue is further complicated by windows, doors, and other entryways into buildings, which lose a substantial amount of heat during winter and gain more heat in summer, causing the refrigeration system to work even harder to keep building inhabitants comfortable.
The installation of a geoexchange system eliminates the immense energy loss by using the relatively constant temperature of the earth as a heat source in winter and a heat sink in summer, as opposed to the highly variable temperatures provided by outdoor air. The energy and cost savings achieved by this improvement can be dramatic.
Bielenberg Ice Arena’s new geoexchange system is estimated to prevent 1,024 metric tons of CO2 emissions and result in $100,000 in utility cost savings. In addition to the geoexchange system, the project also included installation of low emissivity ceilings, a new energy management system, and retrofits on fixtures for water conservation. The entire project is poised to save an estimated 2.6 million gallons of water annually.
Not only is Woodbury’s project saving energy and money, the ice arena renovations have also made a significant impact on the arena’s employees and guests. Project manager, Bob Klatt, stated: “Operation of the system was all done by hand before the renovations. Only a few employees knew how to work the system, and it was extremely time intensive. Now, we can operate our system indirectly. It saves time and makes it easier for everyone.” The new system also has heating capabilities for the bleachers, making guests who come to view an event feel more comfortable.
Woodbury is continuing its efforts toward energy efficiency with more renovations to city buildings. The city remodeled and expanded the public safety building to include a geothermal heating component, and this October began powering their Public Safety building with a new 40kW solar PV array. There is no doubt that Woodbury understands and appreciates the potential for energy efficiency projects to create substantial financial, social, and environmental benefits. The city is pleased with the results of the work it has already completed, and it is excited to explore new possibilities to provide a better future for its community.
For more information, contact Bob Klatt by email at bklatt@ci.woodbury.mn.us, or call 651-714-2580.
Project Profile
- Location: City of Woodbury, Washington County
- Project Cost: $2,362,142
- Funding: $503,900 EECBG; $81,200 utility incentives
- Type of Technology: Ground source heating and cooling; energy efficiency
- Energy and Cost Savings: $100,000 in utility savings; projected savings of 1024 metric tons CO2
- Community Benefits: Reduced maintenance and repair time saves city money; integrated bleacher heating results in more comfort for visitors
Other Local Government Energy Action Ice arena Stories:
- Energy Efficiency Slap Shots: Ice Arena Upgrades In Minnesota Reduce Energy Consumption
- Slick Retrofits Light Up the Riverside Ice Arena in Austin, MN
- Braemar Arena efficiency renovations keep Edina rink dry, cool, and smooth
- Grant enables Elk River energy efficiency project at Energy City ice arena
- Burning for energy savings: Burnsville scores big with Ice Arena renovations
About the Local Government Energy Action Series:
This year-long effort tells the stories of nearly 50 Minnesota municipalities, counties, and schools and the tangible results of their energy-saving efforts to inspire others to take their own actions.
Local Government Energy Action is brought to you by the Clean Energy Resource Teams (CERTs) in partnership with the Minnesota Department of Commerce, Division of Energy Resources.
