Wilde Lake Middle School
Howard County Public School System: Columbia, MD
The new 106,221-GSF Wilde Lake Middle School in Howard County is the first net zero energy school in Maryland. Completed in January 2017, this LEED Platinum school is one of the most energy conscious and efficient schools in the nation, generating as much energy as it consumes over the course of a year as a result of building system efficiencies and on-site renewable energy such as solar power. The project was recognized for its outstanding design innovation and successful implementation, receiving multiple awards, including First Place in the 2019 ASHRAE Technology Awards, Category II – New Educational Facilities.
A ground-source geothermal mechanical system with localized two-stage heat pump units provide space conditioning throughout the school. Ventilation is accomplished through a series of dedicated outdoor air units interconnected to function as one ventilation “system”, with demand control ventilation provided for both classroom and assembly areas. LED lighting fixtures are controlled through a centralized lighting control system, and select building receptacles are switched to facilitate customized scheduling and global shutdown of rooms or sections of the school. The electrical system is continually monitored and analyzed to maintain peak performance through 24 individual building sub-meters. Real time energy information is available for educational use through the school’s web-based Building Dashboard.
Mechanical system components are positioned indoors to maximize the rooftop area available for the photovoltaic (PV) panels needed to offset the annual energy consumption requirements of the school. Electrical production is accomplished through a 633.5 kW PV array comprised of 1450 rooftop and 450 ground mounted panels that produce approximately 829,000 kWh of electricity per year.
The building energy model developed by JPA predicted an annual energy consumption of 639,740 kWh and a resultant site EUI of 20.6 kBtu/sf/yr, yielding a 46.3-percent energy usage reduction compared to the LEED Standard 90.1-2007 baseline. Measured building energy performance results from February 2017 through January 2018 outperformed energy model predictions, with an actual first year energy consumption of 428,300 kWh and a resultant site EUI of 13.8 kBtu/sf/yr.
Photos © Don W. Savage and Coyle Studios
Architect: TCA Architects