The Science of Sustainability
September 01, 2009
Appeared in Sustainable Facility
With 45 geology, biology, chemistry and physics labs, including those with provisions for nuclear magnetic resonance, graphite purification and fluid mechanics, SUNY Geneseo’s Greene Hall has got science covered. The science of sustainability that is.
Part two of a two-phase development which reaffirmed the campus’ place as a leader in science and technology research and education, began in 2007 with the re-development of Geneseo’s Greene Hall as a state-of-the-art, sustainable educational facility. Connected to the new Integrated Science Center or ISC (Phase I), the 51,000-square-foot Greene Hall re-opened last month for the start of the 2009-2010 school year with the same envelope and a completely new set of efficient MEP systems within.
Making Less More
The first step the university took toward achieving sustainability was re-using Greene Hall’s existing structure. This was, of course, also the project’s greatest challenge.
Accommodating new mechanical systems within the 39-year-old concrete structure called for innovative solutions. With limited floor-to-ceiling heights, Syska Hennessy Group utilized the space between the building’s concrete beams to supply and exhaust laboratory fume hoods and run ductwork. Working with the existing structural components and coordinating them to the fullest extent brought together all parties - MEP, structural and architectural — early on in the design process.
Perfecting Lab Mechanics
Laboratories are the most energy intensive spaces within the university environment
because of their required air change rates and the burden that puts on
the building’s mechanical systems. So any attempt at sustainability must incorporate a reduction in energy use at the air handling units. In order to do this, Syska specified a cascading air system for Greene Hall to accommodate the varying needs of the building’s
offices, classrooms and laboratory spaces.
The most significant mechanical energy saver was the use of re-circulating air handling units to bring used air from the facility’s non-contaminated spaces to its laboratories at the required air change rates. The system works by directing exhaust air from an office or classroom space back into the air handling unit (instead of exhausting it outside), filtering it, mixing it with new outside air and delivering it to the lab spaces. Because of the cold temperatures found in upstate New York during the winter months, bringing in less outside air means the heating coils on the air handling units require less energy to heat the same amount of air than that of a 100 percent air handling unit. This results in a reduction in both energy and capital expenditure.
The building’s constant air volume (CAV) control also features energy saving initiatives, including two-position terminal units that control airflow between occupied and unoccupied modes. The CAV allows Greene Hall to reduce air quantities significantly when areas are vacant. During nighttime hours, during school breaks or when classes are not in session, for example, the air change rates are adjusted to a lower set point, conserving energy.
In order to coordinate sustainable features like CAV controls, modern mechanical systems are tied together by a building management system (BMS), which provides facility managers and owners with the ability to monitor how each system is functioning, both independently and in concert with one another. The CAV controls at Greene Hall are set and adjustable at the BMS, where their positions can be changed regularly based on class schedules to maintain indoor air quality.
Measuring energy use plays a significant role in reducing expenditure as well, and it’s the BMS that provides this capability to facilities personnel. Syska designed Greene Hall’s BMS to measure the amount of outside air the air handling units are using at air flow monitoring stations throughout the building. The BMS can trend and compare these usage rates over designated time periods to determine if the building is functioning as designed. Facility managers are then able to use this information to improve the indoor air quality of each space by adjusting set points when appropriate.
Less common and obvious novel techniques were employed in Greene Hall’s laboratory spaces as well, including the lowering of each laboratory’s hood sash position, or its opening. In an effort to reduce the exhaust flow rate by simply reducing the area of the fume hood opening, Syska designed each fume hood to its highest position, opening no wider than 15 inches. By minimizing the opening, Syska was able to reduce the air quantities needed, while still maintaining the 100 feet per minute required for laboratory fume hoods.
Coordinating the Science Campus
Achieving consistency across both the ISC and Greene Hall was also a challenge for the design team. Tying into the same BMS and utilizing the same maintenance and facilities personnel, the attached buildings were seeking to utilize comparable, if not identical, systems and controls. For example, matching occupancy sensors were employed in Greene Hall’s classrooms, offices and lab spaces to control and reduce lighting whenever the spaces are not occupied.
With one “brain” controlling both building’s systems, energy
efficiency will be enhanced. Maintenance and building schedules can be
coordinated, while one central position for the generation of all set points
and trending can provide a baseline for control and comparison over time, making
sustainability at SUNY Geneseo a real lesson in the science of energy efficiency.
Side Bar: Designing Sustainable Labs
Sustainable design is more about the process of systems integration than just employing new equipment. While at the same time, making the appropriate design decisions means finding the right balance and being realistic about the maintenance capabilities of each facility. With the competing demands of education and energy coupled with today’s growing need to minimize costs, finding this balance has never been more difficult.
When it comes to university laboratory spaces, school officials need to be realistic about what they can maintain. The quality and availability of maintenance doesn’t always match up with the latest in green technologies. Assessing each piece of equipment and sustainable process during the design phase is crucial to making the right decision for each space and will give the facility manager the tools to be as efficient as possible during the life of the building.