Green Learning Tools
Green Learning Tools
How energy-efficient initiatives can transform new and existing buildings into meaningful educational and community spaces
By Peter Gisolfi, AIA, ASLA, LEED AP
It’s not enough to just “be green.” Many of the new facilities being built across the country incorporate sustainability features, but green initiatives also must be met with faculty, students, staff, and communities that understand these measures and see that they apply to the entire built environment. Educational institutions that take the lead in green design can serve as examples of how these practices can be incorporated into our everyday lives.
Within this overarching issue are two dilemmas. First, most of the focus on green buildings has been on new green buildings. When a university completes a new green building, its press office will often boast how little energy is consumed per square foot—rarely is energy consumption per person mentioned. The distinction is important because, in most instances, the university simply has added another structure to its existing stock of campus buildings. It has not replaced, torn down, or renovated an old building. In truth, the net effect on the overall campus is that the institution is using more energy per person, not less.
The second dilemma has to do with “building hibernation.” Used in this context, hibernation refers to the time a building is not occupied. There are 168 hours in every week and, in most climates, campus buildings need to be heated (or sometimes cooled) for most of those 168 hours. But a typical school building is used less than 25 percent of the time it is available—only 40 hours or fewer per week, and only 30 or 40 weeks per year. How can educational facilities legitimately brag about energy savings when energy is being consumed while the building is unoccupied, essentially idle, more than 75 percent of the time?
There are relatively simple answers to address these two dilemmas. Rather than focusing on new construction, most of our green building efforts should address how we transform and retrofit existing buildings to make them as energy efficient as possible. Annually in the United States, new buildings constitute only 1 to 2 percent of the total existing space in our academic institutions. Clearly, we are not going to solve our energy problems by focusing on new buildings alone. The issue of building hibernation is more complicated. Of course, we could schedule classes 80 to 120 hours a week, but that likely would be met with resistance from faculty and students.
Making green buildings readily understandable to their occupants should be a key goal. Green, sustainable, and net-zero buildings are best understood when they become part of everyday living and are not just abstract ideas. Educational facilities are great places for occupants to explore and digest how sustainable techniques can be successfully used and measured.
Here are six ways students can learn about sustainable environments:
1. Monitor energy consumption.
If we want to brag about our energy-saving accomplishments, we have to measure them. One approach to measuring is called “submetering.” This involves wiring a building so energy consumption can be calculated in smaller units of space or categories of use, rather than in the whole building. At the Trevor Day School in New York City, each classroom floor in this 14-story building will have its own electric meter. The meters will record the use of electricity for lighting, plug loads, heating, and cooling. Submetering leads to a better understanding of how and at what rate energy is being consumed.
Another aspect of monitoring energy consumption is recordkeeping. Each submeter can be attached to software that prints out records of consumption in readily manageable units. This idea enables students to monitor and compare records.
The first two strategies lead to a third, which is the most important: actual participation in saving energy. At Trevor Day School, submetering seven classroom floors—all identical in size—sets up competition among the occupants to see which grades can use their floors in the most energy-efficient manner. At the same time, students can be learning about the science behind energy conservation.
2. Use obvious, observable, energy-conserving strategies.
Another teaching/learning technique is to construct buildings so that strategies for energy conservation are obvious to the inhabitants and visitors. Operable window shades or blinds, either inside or outside of the glass, are easy to understand and can reduce heat gain. Solar shading devices can minimize sun penetration in the summer and maximize it in the winter.
At the Health Professions and Student Services building at North Shore Community College in Danvers, MA, computer-simulated models were employed to help design the sunshades and light shelves on the south façade of the building. These models, which could be observed and studied by students, calculated the sun’s exact path and angles so that a system could be designed to take best advantage of natural daylight throughout the 58,000-square-foot building.
Many passive solar strategies can be obvious to building users. For example, at the new Kathleen Allen Lower School at the Hackley School in Tarrytown, NY, the classrooms face predominantly north, while the single-loaded corridor that serves them faces predominantly south. The corridor is filled with bright sunshine year-round, while the classrooms benefit from even northern light. The corridor floor, a concrete slab covered with porcelain tiles, absorbs energy from the sun and radiates this energy back to the occupants as heat during the winter.
Other energy-saving practices that are growing in popularity include air-flow strategies to control temperature, lighting controls with occupancy and daylighting sensors, photovoltaic solar collectors, wind turbines, and green roofs, all of which can be used as learning tools for students.
3. Use the building and site as part of the school curriculum.
Lady Bird Johnson Middle School produces as much energy as it uses because of wind turbines, photovoltaic panels, geothermal heating and cooling, and other green technologies and building techniques, according to information released by the institution. The school is a three-dimensional learning space where students throughout the district can learn from “practical, hands-on experiences. Issues such as geothermal science, rainwater collection, solar panel usage, and wind turbine efficiency will help students learn responsibility for energy conservation.”
The Hackley School in Tarrytown, NY, has integrated its recently completed Goodhue Memorial Hall into its Upper School curriculum. Goodhue Memorial, a 1903 building that was nearly destroyed by fire, has been completely reconstructed and expanded. Through a series of sustainable strategies, the project received LEED Gold certification.
Each year since its completion, I have been invited to lecture to the junior year physics classes about the complex operation of the school’s energy-conserving, closed-loop geothermal system. The students respond positively to the statistics that demonstrate the building’s sustainable benefits: The building envelope reduces energy loss through the skin by 70 percent; the geothermal system is 40 percent more efficient than the original conventional system; and the building, which is more than double its original size, uses only 20 percent of the energy required to operate the original building.
4. Treat your building as a science museum.
The beauty of science exhibits is that they explain relatively complex ideas in simple terms. To explain energy conservation, the Lady Bird Johnson Middle School partnered with the Perot Museum of Nature & Science in Dallas to create hands-on exhibits in the main corridor of the school. Touring the installations, students can learn about wind power, rainwater collection, solar panels, and environmental stewardship.
At the new Darien Library, which is heated and cooled by an open-loop geothermal system, flat-screen monitors in the most public areas of the building explain its energy-conserving features. The advantage of flat screen monitors is that messages can be updated on a regular basis.
5. Make the building an example for the wider community.
Today, many people are interested in energy conservation and efficiency. As we employ more visible green building strategies—geothermal systems, wind turbines, photovoltaic panels, careful siting in relation to the sun—and as people begin to learn how well they function, these technologies will become even more widely accepted. In the Village of Bronxville, NY, we renovated the Village Hall, originally constructed in 1942. It is now heated and cooled by a closed-loop geothermal system fed by 20 wells.
6. Make building hibernation understandable.
Techniques for successful building hibernation are not easily understood, particularly in cold climates. When a building is not used constantly, measures need to be employed to maintain stable interior temperatures. The essential elements for success are a well-insulated exterior envelope, and an interior construction system with a high degree of thermal inertia. While interior comfort and stable temperatures are perceptible to a building’s occupants, techniques such as the amount of insulation and thermal inertia are difficult to detect.
An excellent example of successful hibernation is Goodhue Memorial Hall at the Hackley School. The R-value (i.e., the measure of thermal resistance) of the newly reconstructed exterior walls is a high R-35, and the high thermal mass of the interior construction prevents temperatures from changing rapidly. Thus, when the thermostat’s setback feature is employed at night and over weekends, the interior temperature in the building hardly changes. In fact, the main heating load in Goodhue comes from the code-required ventilation air system, which operates only when the building is occupied—approximately 40 hours a week.
The Green Transformation
Creating energy-conserving educational facilities that are truly understandable to their occupants and the wider community is an essential challenge we must address. When taxpayers and donors appreciate what is being accomplished in the institutions they support, similar techniques will be employed in other settings
For the foreseeable future, we will still face the issues of transforming existing buildings into sustainable structures and creating successful hibernation scenarios for underutilized buildings. Hibernation is the more subtle, more difficult condition to observe and monitor. Transformation of existing buildings must be embraced, at least as enthusiastically as new construction, since it is the major energy-conserving task of this nation. While it is more challenging than constructing new green buildings, it is certainly worth the effort.