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Chilled beam technology is seeing increased use in the U.S. as an energy-efficient option that can lower long-term operating costs in buildings. Darren Anderson, PE, CPD, LEED AP BD+C, an associate with Mueller Associates, discusses the advantage of using chilled beams and how the technology can impact the overall design of a building.

Q: What are the basics of chilled beam technology? How does it work?
A: Active chilled beam systems use conditioned air supplemented by ceiling-mounted chilled water heat exchangers. The beams receive air ducted from a central air handling unit and water piped from a central chilled water system. The amount of water varies in order to maintain a comfortable temperature in the space. The ducted air passing through each beam induces room air to flow through its heat exchanger, cooling the room as it circulates. The amount of air delivered to each space is minimal—often only the amount required for ventilation.

Q: What are the benefits?
A: Using water in a chilled beam heat exchanger to remove heat, rather than using conditioned air, is more efficient. Water can carry more energy than air, and this leads to lower operating costs. First costs to use chilled beam systems for an entire building are similar to costs for variable air volume systems when you factor in other design considerations. Chilled beam systems are more expensive than air-only systems with traditional air diffusers, but the ductwork and air handler capacity needs are reduced. There may also be less space required for the mechanical room and ceiling area.

Q: What types of spaces are appropriate for chilled beam technology?
A: We are seeing an increased interest in chilled beam systems for laboratories in particular. Labs often house a lot of heat-generating equipment. The air cannot be recirculated, which can lead to high energy costs. The use of chilled beams assists in reducing the required airflow because the amount of air is driven by ventilation and not by the need to remove heat from the equipment. This lowers the overall amount of energy used.

Q: Does Mueller have any current projects that incorporate this approach?
A: We are currently assisting Perkins&Will in the design of the new Natural Sciences, Mathematics, and Nursing Center at Bowie State University in Maryland. Perkins+Will has had success with the chilled beam approach and has been a proponent from the start of this project. The building has a number of laboratories and was a good candidate for using a chilled beam system.

Q: How has chilled beam technology made a difference in the Bowie State University project?
A: Incorporating chilled beams in the Natural Sciences, Mathematics, and Nursing Center has had a dramatic impact on the overall design. It has been very interesting to see how this technology can alter a design and have a positive impact on the overall cost.

Because the ducts required for the chilled beam system are smaller, the design team was able to reduce the building height by one foot on both the second and third floors. The two-foot reduction overall will save the university more than $300,000, which offsets the cost of the chilled beam system and lowers the life cycle cost of the building as well. Part of the cost-savings is a result of the smaller amount of dynamic glazing needed for the exterior windows, because of the reduced height.

Chilled beam technology is a strong option for new buildings, with a number of clear benefits. In our experience, the best results—and potential cost-savings—occur when the architectural and engineering team works creatively and in close collaboration, to be certain those benefits are realized.

Todd Garing, PE, LEED AP, president of Mueller Associates, has helped engineer several of the firm’s high-profile sustainable projects. On Point explores Mueller’s “green culture” with Todd, and the firm’s commitment to sustainability.

Q: Mueller has a diverse portfolio in sustainable design. What projects have been unique?
A: It’s interesting—one of our earliest projects that focused on conserving energy was for the White House in the 1970s. We designed a solar energy system there. That was before my time, but I did have the opportunity to work on another historic property, at Thomas Jefferson’s Monticello. The visitor center there is a LEED-Gold project, and it incorporates an innovative geothermal chiller/heater system. We like to think that Jefferson would have approved—it was cutting-edge but organic in that it made good use of the land.

Q: What are some of your significant Sustainability projects?
A: Two of our higher education projects have achieved LEED Platinum: the Angelos Law Center at the University of Baltimore and the Center for Natural Sciences, Mathematics, and Nursing at Bowie State University. Both of these projects incorporated cutting-edge technology. The Angelos Law Center has radiant heating and cooling in the slab floor. The Center for Natural Sciences features chilled beam technology. At the LEED Gold University of Maryland Eastern Shore, the Engineering & Aviation Science Complex, we incorporated geothermal technology.

Q: How has the firm approached the challenges of incorporating sustainable design measures?
A: We’ve been working with institutional spaces for many years, so we’ve always had a focus on energy conservation—incorporating control strategies and more efficient equipment, or laying out the pipe and ductwork in a more effective configuration. The LEED process has essentially validated much of what we have been doing over the years. The focus has evolved so that it is not just an energy and cost-saving focus, but we are thinking more broadly in terms of environmental awareness. It challenges us to think in terms of each and every detail and what can be done more effectively to conserve resources.

For example, many people don’t realize how much water is produced through A/C condensate. For the University of Maryland Baltimore County Performing Arts and Humanities Building, we were able to predict that as much as 40,000 gallons of water from condensate could be collected a month during the summer. That’s a lot of water—it could be used for toilets, irrigation, or cooling tower make-up. For that project we utilized the A/C condensate as well as the rainwater collected from the roof to serve the irrigation system.

Q: How integral are sustainable strategies to the firm’s work? How much of Mueller’s staff focuses on this aspect?
A: The sustainability framework guides all of our projects—it’s inherent in our approach and our process. What is exciting to us is that the LEED process really taps into the “brain power” of the firm. We have a lot of smart people here—people who are good at coming up with ideas and new strategies. A large percentage of our professional staff is LEED accredited, so it has become integral to our practice and the way we approach our work.

Rebecca Fischer is a graduate of Penn State and has worked with Mueller Associates since 2006. She has been using Autodesk’s Revit and Navisworks software for building information modeling (BIM) since 2006.

Q: What was your introduction to Revit? What were your early impressions of the modeling software?
A: I’ve been using Revit MEP here at Mueller since 2006. I graduated with my engineering degree in 2003, and the program didn’t exist when I was in school. Our management at Mueller recognized early on that we needed to embrace this technology, and provided us with comprehensive training. We saw where the industry was going. Our first project using BIM was the new Visitor & Admissions Building at the University of Delaware. At first, the software was not as well suited for mechanical/electrical engineering, but it has improved by leaps and bounds.

Q: What has improved since your earliest use of the software?
A: At the beginning, we were only able to model ductwork and electrical systems. Now, we have the ability to model just about every mechanical, electrical, plumbing, and fire protection system. We can do the electrical panel schedules, which we couldn’t do before. The software has advanced tremendously, and our own training and proficiency has improved. Our entire professional and production team is trained in Revit. It makes it a lot easier when we’re using the technology across the board, rather than having just a few Revit “specialists.”

Q: How many of Mueller’s current projects are using BIM technology?
A: Nearly all of them. It’s one of the biggest differences from three or four years ago. Nearly every project, including our university and museum work, is done in Revit today. It’s become the standard, especially for large projects.

Q: What advantages do you see as you work with BIM?
A: The software really lends itself to a much more integrated approach to design. We can see the other disciplines’ design intents in a 3-D environment, with real-time updates. We export the models to Navisworks so that we can do our own clash detection. Mueller also has a comprehensive Revit-based library with details on equipment and fixtures. It streamlines our design time and effort and can be used to support life cycle and maintenance programs.

Q: How do you keep current with updated programs?
A: We participate in the Autodesk user groups and Autodesk University. I’ve also had the opportunity to visit the Autodesk offices in New Hampshire and test their last two Revit MEP products prior to release and provide feedback. We have a lot of knowledge about BIM in this office and that’s based in part on our experience but it’s also a result of our commitment to continue to learn and take advantage of the latest resources.