The Science of Green
Aug 1, 2009 12:00 PM, By Raymond Cekauskas and Mark Hartmann
An integrated approach can incorporate sustainability into complex science and laboratory facilities.
The University of Cincinnati’s Center for Academic and Research Excellence (CARE)/Crawley Building is one of the largest health-science research complexes in the country. Designed to achieve LEED gold certification, the facility houses some of the most technically advanced laboratory research and teaching space in the nation. Photo courtesy of Brad Feinknopf/Feinknopf Photography
If you could envision a university campus as a fleet of buildings in an ocean, the science laboratory building would be the aircraft carrier: big, powerful and bristling with technology. For a campus facilities leader overseeing the growth of a collegiate setting and the efficient function of its buildings, when the opportunity arises to build a new laboratory facility, you might say his or her ship has just come in.
When one considers the enormous cost of science laboratory buildings, it's no surprise that the stream of environmental consciousness that has swept through campuses has had a profound effect on the design and engineering of these complex buildings. Advancing technologies, government regulations and rising energy costs all are driving the push to design greener building systems.
And although science and laboratory buildings are by far the most complex and energy-intensive buildings on campus, they also can be models of effective energy management, carbon-footprint control and sustainability.
Sustainable sites
Master plans, synergies with existing facilities and donor preferences often affect where a new building is situated.
Administrators have many options regarding sustainable design, such as protecting existing habitats, using previously developed sites and staying away from “virgin” land. The goal of protecting important habitats starts in the design phase with a clear understanding of the site's opportunities and constraints. Proper siting, condensed building footprints, and minimizing heat-island effects through the use of high-albedo materials, pervious paving and reduced parking areas, all play a role. A habitat with abundant trees provides benefits by shading building and exterior spaces, and reducing the cooling load.
Consider a storm-management approach that uses bioswales instead of piped sewers. They can be made into attractive, green site elements that remove water efficiently while cleaning it along the way. With smart and careful planning, new campus projects can coexist with nearby wetlands and bodies of water.
Designing a living place
The nature of scientific exploration requires facilities that meet current demands and are flexible enough to effectively respond to evolving scientific challenges and protocols. Module-based space planning is a strategy to give discipline and clarity to architectural and engineering systems. Flexible, mobile casework and furniture systems with plug-in utility connections are replacing traditional fixed benches with hard-piped services. The well-designed lab building will not only save operational and retrofit costs, but also will be a “living” place that can be changed and molded as required.
The building envelope also plays an important role in the sustainability of a facility. A design that responds to solar inputs through smart orientation, roof overhangs, brise-soleil and other devices is more environmentally responsible than a concept based solely on architectural considerations. A science and laboratory building should respond to site-specific and regional influences. Light-colored, heat-reflecting roofs; high R-value insulation; high-performance, low-e, thermally broken glazing systems; and the use of regional materials all help in making a building more sustainable.
By maximizing the use of natural lighting, schools can save on energy costs and increase comfort, which enhances productivity. Generally, daylighting can adequately light 15 feet into a building when measured from the perimeter. Adding devices such as light shelves and clerestory windows can double that distance. Architects should utilize the best lamp and lighting-control technologies. Incandescent lamps use only 10 percent of their energy to make light — the rest is lost as heat. The good news is that even the most advanced T3 fluorescent lamps are being supplanted rapidly by advanced LED products.
Interior environments are important to consider. Additional air contamination that is breathed in lab buildings can occur from relatively benign sources found in paints and finishes. Use ASHRAE 62 as the standard for ventilation and indoor air quality. Requiring zero- and low-VOC carpets, paints, adhesives and sealants will reduce harmful effects from volatile organic compounds (VOCs).
Prior to occupancy, air-quality testing, carbon dioxide monitoring and a two-week flushing-out phase will help remove unhealthful VOCs generated from new materials and construction debris.
Aggressive energy control
Science and laboratory buildings are alpha consumers of electrical power. The key for aggressive energy conservation without compromising functionality is sophisticated engineering coupled with high-quality systems. Laboratory mechanical systems often require 35 to 50 percent of the construction budget.
Benchmarking similar laboratories is a good way to anticipate operating and maintenance costs for energy. This should be done before engineering design is complete. To verify that a building is performing most efficiently, hire a commissioning agent. Some other keys:
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Reuse applied heat energy through a recovery system. Capture heat energy from lab exhaust, and use it to preheat fresh outside air. Capture waste heat from the condenser water system and apply it to domestic hot-water heating. The use of recovery coils and dessicant wheels can recover enormous amounts of energy. In some parts of the country, the payback for these systems can be just a year.
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If an institution has boilers, install economizers. Instead of a central hot-water system for domestic use, consider using smaller-scaled hot-water tanks distributed at locations of need with temperatures at 105°F vs. 120°F.
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Partial-load system efficiency is important because most lab systems do not operate at identical levels of intensity consistently over time. Use equipment designed to operate at efficiently under partial and varying loads — a very common condition with higher-education laboratories.
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Officials should review requirements for fume hoods carefully so they can reduce their quantity and size. Use low-flow hoods that respond to changing levels of experimental activity, as well as snorkels and ventilated storage cabinets that pinpoint exhaust loads. Follow the American National Standards Institute Z9.5 ventilation standard for fume hood and room-pressure control.
At a macro building level, use variable-volume supply and exhaust systems to reduce ventilation during unoccupied times. If the system design is based on minimum air-change rates vs. demand-generated cooling or makeup-air loads, then constant-volume systems should be considered.
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