Can new trends in learning and teaching increase the energy efficiency on American campuses? In the quest to build more energy-efficient academic space, education institutions face a dilemma. In an average week, instructional space on most college campuses in the United States is occupied only about 14 percent of the time, or about 24 of the 168 hours of each week. Classrooms can sit empty 144 hours every week. In addition, during many periods in the average year, classrooms are not used at all.
At the same time, the digital revolution is changing the way we teach and learn dramatically. For example, in fall 2009, nearly 30 percent of all U.S. college students took at least one course online, and this trend is increasing. Today, about 12 percent of college credits are offered online. At Texas Women’s University, the entire graduate program in library science is offered online; there are no classrooms.
People might conclude from these observations that classroom space is plentiful. Yet, many institutions continue to construct new buildings. Frequently, academic institutions excitedly announce additions to a new building, so the underlying assumption is that more space is needed. Ironically, even a new green building increases energy use and the carbon footprint.
Emerging modes of learning
Today’s students are learning in ways that were unknown a few years ago. Yet, they do their on-campus learning in buildings designed according to traditional modes of education. These observations raise some simple questions:
•Why brag about a new building that reduces energy use by 50 percent of the average building if the space is not needed, and if the new building will not be used intensely?
•Why do American campuses have so much existing space, mostly underutilized?
•How can schools use existing academic buildings more efficiently?
•Is the basic academic calendar incompatible with the desire to use buildings efficiently?
•Is it better to have one older, less-efficient building in use 50 percent of the time rather than three newer, energy-efficient buildings in use only 14 percent of the time?
•The conventional wisdom says new buildings should be green; why not renovate existing buildings to make them green?
•Should a school use what it has more efficiently—in terms of intensity of use and energy consumption?
Education institutions need to find a reasonable way to measure energy consumption and energy efficiency. The usual measurement considers energy consumption per square foot. As such, a typical announcement might point out that a new academic building uses only 40 percent of the energy of an average building of the same size.
This type of calculation misses the basic point. What if an existing building of 10,000 square feet accommodates 100 students for 40 hours each week, while the new building of 10,000 square feet accommodates 10 students for 40 hours each week? Wouldn’t the average older building be more energy-efficient? Clearly, the reasonable calculation is to look at energy cost per student and staff hours in the building.
Let’s say a private East Coast university wants to become one of the greenest campuses in America. The university’s buildings total about 12.5 million square feet for 10,000 students—about 1,250 square feet per student. A nearby public university also wants to be greener; the university’s buildings total 2,380,000 square feet for 17,000 students—about 140 square feet per student. How can the campus with 1,250 square feet per student compete for energy efficiency with a campus that has 140 square feet per student? The combination of faulty methods of calculation and changes in our modes of learning and teaching are complicating the prospect of increasing energy efficiency on American campuses.
Nevertheless, it is possible to increase energy efficiency in academic buildings. Some simple techniques:
•Hibernation. Create a building and a mechanical system that uses considerably less energy when the building is unoccupied.
•The Thermos bottle effect. Create an exterior envelope that is extremely resistant to heat transfer; when no ventilation is required, virtually no energy is consumed.
•Renewable energy. Construct buildings that consume no energy because they use only renewable sources.
•Intensity of use. Triple the intensity of use of existing space, thereby increasing the energy efficiency per student hour.
The dilemma most schools face is that most of the buildings were constructed when energy was inexpensive, and the energy budget for a campus was inconsequential. The astoundingly inefficient and costly inherited situation affects almost all existing academic buildings in the country.
Changes in space utilization
For a more balanced view, consider the most obvious changes in patterns of space utilization. The traditional spaces for teaching are lecture rooms, classrooms, seminar rooms, laboratories and studios. With the exception of laboratories and studios, these spaces are designed for teacher-centered learning, which is oriented toward transferring information from the teacher to the student.
Recently, other types of learning settings have developed; these include the learning commons, distance-learning classrooms and online courses. These spaces and techniques are typically self-directed, and centered on problem-solving and collaboration.
The traditional campus learning experience is changing. With more online courses, less space will be required. In the future, campuses can expect to reconfigure and transform existing academic space to accommodate emerging modes of learning. They also can expect to use instructional space more intensely. The purpose will be to reduce energy consumption in total and to use significantly less energy per student.
As campuses accommodate new modes of learning and teaching, the following suggestions can serve as a pathway to greater energy efficiency:
•Reduce waste, and make buildings more sustainable.
•Recognize the current trends in learning and teaching, and relate these trends to space utilization in campus buildings and to long-term sustainable goals.
•Measure space utilization in academic buildings as a factor in sustainable practice.
•Employ simple techniques to increase the energy efficiency of existing buildings.
•Formulate a method to measure the energy efficiency of the entire campus, based on characteristics such as site area, building area, and overall space occupancy and utilization.
•Measure the energy consumption of academic buildings and academic campuses relative to the population of students and staff.
•Produce or harvest energy on campus.
•Address the best current practices used by university and school planners to reduce building program size based on better scheduling practices, flexible design for multiple types of occupancy, distance learning and other methods to avoid underutilized space.
•Consider ways buildings can accommodate diverse activities in the same space; create multi-function buildings.
•Work toward a future in which schools and campuses are net-zero energy users.
A new future
Central heating and air conditioning are the basis for energy inefficiency. Many have relentlessly followed a path to use energy extravagantly—all the moreso because academic buildings actually are occupied so infrequently. It wasn’t always this way. Consider two examples from the past:
•Until 1964, the Pantheon, constructed in 126 AD, almost 1,900 years ago, was the largest span reinforced concrete dome in history. At the top of the dome is an open oculus that brings in natural light and air. Beneath it is a floor drain. There is no heat or air conditioning in the building, yet it is used in all seasons and has survived through all these centuries.
•Thomas Jefferson (1743-1826) designed the central campus at the University of Virginia during the last years of his life. In one of the simple efficiencies on that campus, the classrooms were situated on the first floor of the professors’ houses. The house was heated with fireplaces, which also served the classrooms. Early in the 19th century, Thomas Jefferson had designed a multi-use academic and residential space.
Schools can imagine a new future of space efficiency and still learn important lessons from the past.
Sidebar: Case studies
In order to better understand the types of change that are taking place, look briefly at three case studies: The Spitzer School of Architecture at the City College of New York; instructional space in the physics department at Cornell University, Ithaca, N.Y.; and Goodhue Memorial Hall at the Hackley School in Tarrytown, N.Y.
The Spitzer School of Architecture is housed in a 1950s library that was renovated and transformed. The new School of Architecture, first occupied in August 2009, is a 110,000-square-foot building that accommodates 450 to 500 students. Pin-up exhibition space and corridors occupy 19,000 square feet; 31,000 square feet is for studio space; 10,000 square feet for conventional classroom space; and 8,000 square feet for administrative space. (Not included in these calculations are additional circulation space, the library, service and storage space, mechanical space, the model shop and the community design center.) The unique aspect of space utilization is that students and faculty use the studios about 50 to 60 hours per week, vastly increasing the intensity of space utilization within the building.
At Cornell University, 11,000 square feet that previously had served as part of the science library will become instructional space for the physics department. The project will be completed in 2013-2014. The space will contain eight classrooms totaling 5,400 square feet and 4,750 square feet for individual and group study space. The efficiency advantage is that nearly all of the space will serve double-duty: the study space also is circulation space, and the classrooms, which will be occupied about 30 to 40 hours per week for daytime instruction, will accommodate homework sessions and faculty advising in the evenings. The typical classroom space will be used about 40 to 50 hours per week, and the study space just as intensely. This future pattern of utilization represents a dramatic increase in the intensity of use.
The Goodhue Memorial Hall reconstruction at the Hackley School, Tarrytown, N.Y., transformed and doubled the size of an existing academic building in a manner that increased student utilization and decreased energy use. When the Goodhue building burned down in 2007, it contained about 7,500 square feet devoted to the middle school and upper school library. It was a 1903 stone building with single-glazed windows and outdated mechanical systems, all of which combined to make the building extremely energy-inefficient.
The transformed building contains about 17,000 square feet—more than twice the original square footage—the result of adding a second floor plus useful space at the basement level. The new building contains the library in 8,000 square feet as well as classrooms, seminar rooms, a student lounge, administrative space and the school archive. The intensity of space utilization has increased enormously, and the energy consumption of the new building—heated and cooled by a geothermal system—is between 10 and 15 percent of the energy consumption of the original, smaller building.
Gisolfi, AIA, ASLA, LEED AP, is a professor of architecture and landscape architecture and chairman of the Spitzer School of Architecture at the City College of the City University of New York. He also is the senior partner of Peter Gisolfi Associates, Architects, Landscape Architects, LLP, Hastings-on-Hudson, N.Y., and New Haven, Conn.