Creating a more efficient SAS

As the bell rings and students file out of the conference room in the high school student life center, the lights dim and the air conditioner turns off. The same thing happens when areas of the main room are empty, or when a counselor leaves her office. Thanks to occupancy sensors installed during the student life center's construction last summer, saving energy in unused spaces no longer depends on someone remembering to press a switch.

But does this really save enough energy to make it worthwhile? The answer is a resounding yes: during the first semester, SAS facilities staff measured 73 percent lower energy consumption in the student life center than the space previously used. This pilot project is proving that installing new technology can indeed save a great deal of energy through improved efficiency, with exciting implications for its wider use on campus.

Today, innovative options for maximizing our use of energy, water, and other resources are proliferating. Under the leadership of Facilities Director Anthony Wong and Sustainability Manager Prescott Gaylord, a number of pilot projects are underway that we hope will lead to campus-wide improvements. Already we see remarkable results, as these efficiency initiatives have saved over $286,000 this school year. SAS has a long history of leadership in environmental sustainability, and new technologies, along with growing community awareness, are helping us continue this focus in current and future facilities initiatives.

Occupancy sensors are only one of several cost-effective upgrades that we can apply to our current spaces, especially when systems are replaced due to malfunction or obsolescence. As air conditioning accounts for over half of our energy use, greater aircon efficiency is certainly worth our efforts. We are currently testing the effects of new software and controls on one of our chillers. This has revealed that such improvements can save 15 to 25 percent of the chiller's energy use. Our seven chillers are all over fifteen years old, and without such replacement they would be approaching obsolescence. We calculate that retrofitting all seven school chillers could result in a savings of ten percent of our overall energy bill!

SAS energy use per year (megawatt hours)
(blue bars represent the energy produced by solar panels at SAS)

Thermostat and lighting improvements are also helping us save energy. Many of our older thermostats control blocks of rooms that must stay at the same temperature or turn on and off at the same time. Giving users more control can eliminate unnecessary cooling, improve dehumidification, and keep everyone more comfortable. New monitoring and analytics systems are helping us identify best practice settings for our chilled water and pump pressures. Changing traditional AC fans to DC fans in our air-handlers is also worthwhile. We recently finished retrofitting all 10,000 SAS lighting installations with high-efficiency LED bulbs. This multi-year project will result in a savings of seven percent of our overall energy costs going forward.

SAS energy use breakdown

Students can see renewable-energy technology at work in the middle school library's new solar charging station. Using energy from our own rooftop photovoltaic array, the charging station has room for six devices. Collaboration with the middle school library staff and interested teachers made this project possible and linked it directly to student learning. Besides being a hit with middle schoolers, the charging station allows us to evaluate the benefits of installing such stations in classrooms.

In addition to conserving energy, SAS also seeks to conserve water, a precious resource in Singapore. By reducing evaporation and runoff, drip irrigation can save 50 to 70 percent of the water used by traditional sprinklers. We now have three such systems, and are planning to expand drip irrigation to all plantings. A water monitoring system installed last year is also helping our facilities team to find and fix wasteful leaks in campus pipes. As we plan for campus upgrades, we are also investigating how to make better use of captured rainwater in our groundskeeping.

SAS water consumption per year (cubic meters)

Moving forward, sustainability technologies and standards will be integral to our renovation and construction projects. A task force of students, parents, faculty, staff, and contractors is developing an ambitious, school-wide "Zero Waste Plan" to eliminate all net waste from plastics, paper, and disposables. If it proves possible, this action plan will truly set SAS apart from other large schools and companies. Even if it is not yet feasible, a low-waste campus will give our students and community many opportunities to develop responsible habits for more sustainable living, while saving the school resources and money. We look forward to making SAS ever more efficient as we educate our students to be leaders in environmental stewardship and innovation.