Liberty Middle School
La Vista, Nebraska
Alvine Engineering was instrumental in developing a comprehensive energy management approach and providing the mechanical, electrical, plumbing, architectural lighting, and commissioning for this new 127,779-square-foot middle school for an initial student population of 360 students. The systems required sizing to accommodate a future addition of 30,000 square feet. In addition to the more obvious financial benefits of an energy-efficient and sustainable school design, there are educational benefits to be achieved by incorporating daylighting into the design of 21st-century school buildings. Studies have shown that students in rooms with daylight integration experience 20% higher math scores and 26% higher reading scores compared to those tested in rooms with less daylighting. Daylighting analysis and design services were included in the project scope to capitalize on these benefits to student performance and energy saving opportunities.
- Vertical water-cooled heat pumps with individual space control are located in individual mechanical clvwvwosets accessed from the corridors to allow monthly maintenance to be performed without disrupting the students.
- The heat pump water loop is a ground-coupled vertical well field. Emergency backup heat for the ground-coupled heat pump loop is provided using a high-efficiency natural gas boiler.
- Code-required outside air for the ground-coupled heat pump system is provided by seven energy recovery units. The units include direct expansion cooling and hot gas reheat to dehumidify the outdoor air and an electric heating coil to prevent frosting on the energy recovery unit heat transfer surface during extremely cold ambient air temperatures. The cooling and heating portion utilize the geothermal ground loop.
- Each space includes a CO2 sensor used to control the amount of outdoor air each heat pump requires. As the overall outdoor air flow reduces the energy recovery unit fan speed is reduced to save motor energy.
- Studies have shown that students in rooms with daylight integration experience 20% increased math scores and 26% increased reading scores compared to those tested in rooms with less daylighting. Daylighting analysis and design services were included in the project scope to capitalize on these benefits to student performance and energy saving opportunities. Light shelves and clerestory glazing were incorporated in the design to bounce light from high-daylight exposures into the interior. LEDs and dimming switches were also utilized to maximize energy savings.
- Recipient of the ACEC Nebraska’s Honor Award for Excellence in Energy-efficient Design. Also awarded Illuminating Engineering Society Illumination Award of Merit.