Great River Energy’s new 180,000 sf headquarters facility, which completed construction in 2008, is one of less than 100 buildings in the world—and the first in Minnesota—to achieve LEED Platinum, certified with 56 points. The building uses 45% less energy than a comparable facility, against the Minnesota State Code. Among its advanced energy-saving strategies, it employs an in-lake geothermal HVAC system, daylight harvesting, in-floor displacement ventilation, on-site solar panels, and a 200-kW wind turbine.

The Weidt Group provided Energy Design Assistance to the Design Team and Owner through detailed analysis of numerous energy-efficiency options. The Weidt Group facilitated intelligent decision-making by providing annual energy savings potential and cost paybacks.

Energy Conservation and Efficiency Measures

• Linear building with longer sides north and south
• Minimum windows on east/west walls to reduce unwanted solar heat gain
• High-efficiency glazing system
• Dimming daylighting sensor control of electric lights in private offices and open offices
• Stepped daylighting sensor control of electric lights in atriums
• Occupancy sensor control of lights in storage rooms, dining rooms, garage, open offices, private offices and conference rooms
• High-efficiency lighting design
• Waterside economizer on interior heat pumps
• Under-floor air distribution system
• Carbon dioxide sensor control of outside air in multiple spaces
• Energy-efficient elevators
• On-site renewable energy, including photovoltaic panels and wind turbine, which generates about 15% of building’s energy requirement