Colorado Springs, CO 80923
There is a common misconception that energy-efficient design comes at a higher cost. But Colorado School District 11's Freedom Elementary School, the design of which achieved Designed to Earn the ENERGY STAR in 2007, proves that energy-efficient design can mean lower costs over the lifetime of a building.
The district has saved over $9.4 million since implementing an energy reduction program in 2000, and Freedom's energy-efficient design ensures that the district will continue to realize large utility savings.
Some of Freedom's biggest savings will most likely come from simple, inexpensive design choices. District Energy Manager Mark Ferguson explains that District 11's elementary schools are usually single-story structures, but the Freedom design team reduced the building envelope and footprint by designing a two-story building in an effort to reduce heating and cooling intensity. They also specified high levels of insulation.
To reduce artificial lighting needs, the Freedom design takes advantage of natural light through daylighting and Solatube® skylights.
The design features advanced energy-saving technologies and systems as well. A demand-controlled ventilation system measures the amount of carbon dioxide in a room and uses this information to regulate indoor/outdoor air exchange. No energy is wasted in ventilating empty classrooms, and the system maintains indoor air quality while saving energy.
A geothermal heat pump takes advantage of ground temperature to reduce heating and cooling costs. In the winter, when the ground is warmer than the air, water passes through a subterranean system and exchanges acquired heat with the HVAC system, reducing the amount of energy needed to warm external air. In the summer, when the ground is cooler than ambient air, the subterranean system reduces the cooling load.
"We said total building energy use had to be 25 kBtus per square foot per year," Ferguson comments. "And we were only going to pay a certain amount for the whole project." At first, no one believed the goals could be met, but the district refused to compromise, and it ultimately selected a design that met its energy efficiency and budget requirements.
As proof that the team's design strategies were effective, Freedom Elementary School went on to earn the ENERGY STAR label in 2009.
The PSD Green Team measured the effectiveness of insulation at other PSD schools using infrared cameras. They found that applying spray foam to a building's exterior was more effective (and much less costly) than building thicker walls with more insulation. This information factored into the design of the Bethke building envelope.
The Bethke design also placed heat wheels and solar panels on the roof, both of which will help the school reduce its energy use without compromising aesthetics.
"As long as we've done research, we're not afraid to try new things," Reeve said.