Case Study: Zero Energy

Bluestone Elementary School

Harrisonburg City Public SchoolsHarrisonburg, Virginia

Reducing Energy Consumption by 60%

As one of Virginia’s best-performing schools, Bluestone Elementary exceeded the district’s energy efficiency goals while maintaining the project budget. By implementing high-performance design strategies, the school not only achieved zero energy but is also a sustainable, state-of-the-art learning environment that requires less maintenance and enhances occupant health and wellness. Bluestone sets a new benchmark for educational facilities in terms of sustainable design and operation.

The Challenges

  • Design a zero-energy school while staying within budget
  • Select an HVAC system that is easy to operate and maintain
  • Create a holistically sustainable learning environment that enhances learning outcomes and prioritizes occupant health and wellness
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CMTA is passionate about how a building and its systems can be utilized as a teaching tool. Created with Sketch.

Bryce Powell

VMDO Architects

The Solutions

At the project’s outset, Harrisonburg City Public Schools tasked the design team with constructing an elementary school similar to the district’s typical facilities while adhering to their standard budget constraints. However, by setting ambitious energy-use targets, considering energy-efficient HVAC and lighting options, and collaborating closely with the owner, CMTA challenged the district to pursue a zero-energy design, drastically reducing both the facility’s energy consumption and operating costs—all while staying within budget.

CMTA worked closely with HCPS to evaluate the most efficient HVAC and lighting systems, focusing on options that would not only address the district’s maintenance concerns but also significantly reduce energy consumption. During initial discussions, HCPS described recent maintenance challenges encountered at other schools within the district, such as difficulties in obtaining replacement parts for new equipment in conventional boiler/chiller/VAV systems. As a result, the district wanted to ensure Bluestone Elementary’s HVAC systems were easy to operate and maintain. Based on CMTA’s recommendation, the district selected a geothermal heat pump system, as it was easier to maintain while consuming less energy than the district’s existing schools.

To further reduce energy consumption while remaining within budget, CMTA coordinated closely with the architectural team to ensure a cohesive, high-performance lighting design. We utilized energy-efficient LED lighting fixtures for maximum effect, while decorative fixtures were provided in high-impact areas. A granular, recursive approach to lighting simulation ensured reduced fixture counts and prevented over-lit spaces. This strategic approach helped the project to bid under budget while achieving a Lighting Power Density (LPD) of 0.43W/sf, or almost three times better than the code minimum.

Sustainable Design & Maintenance

The construction of sustainable, 21st-century schools goes beyond mere structural innovation to foster a holistic learning environment. By integrating break-out learning spaces, larger windows that afford expansive views, and sophisticated ceiling systems, these educational spaces offer unparalleled connection to the outdoors. CMTA’s team strategically implemented MEP systems that not only integrate into the architectural design but also reduce noise pollution, enhance air quality, and maximize natural light.

Recognizing the critical role of maintenance in enhancing the effectiveness of sustainable design, CMTA minimized components that require maintenance by eliminating complex systems and controls. For instance, by simplifying control systems, avoiding high-maintenance devices such as CO2 sensors, and eliminating inefficient elements like electric unit heaters, CMTA’s designs inherently reduce the need for frequent upkeep. This approach not only extends the lifespan of the building’s components but also underscores our commitment to creating educational spaces that are as sustainable in their operation as they are in their design.

The Results

Operating at a 17.1 EUI, Bluestone Elementary is one of Virginia’s best-performing schools. By balancing high-performance design with budget constraints, CMTA was able to deliver Harrisonburg County Public Schools a zero-energy school without additional first costs. Not only is the facility energy-efficient, but it also reduces carbon emissions and enhances learning outcomes.

CMTA was proud to design this LEED Gold facility, further solidifying our belief that all schools nationwide can achieve outstanding learning environments while pursuing low-energy goals, both without increasing the budget or requiring extraordinary maintenance efforts.

Bluestone Elementary Energy Use

[{"x":"JAN","Baseline":"3.8","Actual":"1.5"},{"x":"FEB","Baseline":"7.3","Actual":"2.9"},{"x":"MAR","Baseline":"11.5","Actual":"4.6"},{"x":"APR","Baseline":"15.7","Actual":"6.3"},{"x":"MAY","Baseline":"20.2","Actual":"8.1"},{"x":"JUN","Baseline":"23.2","Actual":"9.3"},{"x":"JUL","Baseline":"25.2","Actual":"10.5"},{"x":"AUG","Baseline":"28.2","Actual":"12.6"},{"x":"SEP","Baseline":"33.2","Actual":"14.7"},{"x":"OCT","Baseline":"37.4","Actual":"16.6"},{"x":"NOV","Baseline":"41.2","Actual":"18.3"},{"x":"DEC","Baseline":"45.2","Actual":"19.9"}]
What does this data mean?
Baseline: US National Median School Energy Use
Actual: The measured energy use of this project