How Rice Hall Will Help Trim Buildings' Energy Consumption

January 25, 2010

January 25, 2010 — Buildings such as the one you may be working in now or the home you will sleep in this evening account for 40 percent of the United States' energy consumption. With lights ablaze and heating and cooling systems running around the clock, it's easy to see how the usage adds up.

The University of Virginia Engineering School's Rice Hall Information Technology Engineering Building, which will open in the fall of 2011, will facilitate the type of research that can help reduce buildings' energy consumption. With sophisticated technologies for heating, cooling and lighting, plus energy recovery systems, Rice Hall will function as a "living laboratory" for energy use.

When Rice Hall opens, students and faculty who are going about their daily routines in the building will help researchers learn how to optimize the latest energy technologies for large buildings. The building's powerful instrumentation systems will collect data that demonstrate not only superior technologies, but also how to optimize their use. The research also could inform behaviors such as closing doors or powering down equipment to help reduce energy consumption.

"Thanks to the generosity of Paul and Gina Rice, who provided the main funding for the building, Rice Hall stands to transform the way the University community works together to learn about and improve energy use and consumption," James H. Aylor, dean of the School of Engineering and Applied Science, said.

Researchers will be able to compare individual floors using different heating and cooling systems, and conduct experiments to optimize the performance of these technologies. In addition, five labs and five offices will be outfitted with instrumentation to compare different heating, cooling and lighting technologies and record detailed data.

These instruments include sensors for a variety of environmental parameters to keep tabs on electricity use, air quality, humidity, occupancy, temperature, plug power and lighting power. Sensors will be sensitive enough to monitor whether or not a door was open for a given period of time or the position of window shades during peak sunlight hours.

"The instrumentation in Rice Hall will capture all the energy coming into and consumed within the building," said Mitch Rosen, the Engineering School's chief technology officer.

Researchers in the building will monitor two promising though not yet widely adopted heating-ventilating-air conditioning systems in the United States – an active chilled beam system and a low-temperature variable air volume system.

In contrast to conventional HVAC systems, which deliver air at different temperatures through ducts, chilled beams use water to remove heat from rooms. Rice Hall's use of active chilled beams represents one of the latest generations of this technology, as it couples chilled beams with the ventilation system to simultaneously cool rooms while providing ventilation. Active beams can also be used to heat rooms.

Variable air volume systems use different air-flow rates to control room temperature based on the cooling requirements of the room, such as the number of occupants. The low temperature air for the system will be generated by a dedicated chiller and ice storage unit. The practice of making ice during off-peak periods (such as the middle of the night) and melting ice during the peak sun load (thus offsetting the use of electricity to run the chiller during the middle of the day when the electrical rate charge periods are highest) is a key area of exploration for researchers. With the ability to supply lower-temperature air to the offices and labs than is possible through conventional systems, less air is needed to keep the rooms cool, thereby reducing the size of the fans, allowing for the use of smaller motors that require less electricity to run them, and permitting smaller duct work.

Once research gets under way, Rosen hopes the school's researchers will be able to share data on best practices with the academic community, as well as with government and industry collaborators. Rice Hall will be the new home for the computer science department, allowing its faculty and researchers to collaborate with teams of engineers, including those from the departments of Systems Engineering, Mechanical and Aerospace Engineering, The Charles L. Brown Department of Electrical and Computer Engineering, as well as by researchers throughout the University.

"We would like to write the handbook on optimizing these technologies to minimize energy consumption," Rosen said.

Andrew Persily, leader of the indoor air quality group at the National Institute of Standards and Technology in Gaithersburg, Md., is familiar with plans for Rice Hall and believes the structure offers an exciting opportunity to look at new technologies that could help reduce energy consumption from the operation of buildings.

"Research conducted in Rice Hall will be helpful to the research and design community, as well as to the broader building community," Persily said. "It will hopefully show how best to incorporate the most effective and efficient energy technologies into a building."

A first step for reducing energy consumption is to reduce the energy needs of the building. To accomplish that, a building must be well-insulated and properly ventilated to take advantage of outdoor weather conditions, while also keeping the air quality clean for occupants. Other considerations for reducing energy needs include everything from how the building is oriented to window design.

"Rice Hall's design and use of innovative ventilation systems will help reduce needs and, in turn, energy use," Persily said.

When completed, Rice Hall will be more than just a structure in which to hold classes and conduct research. The building itself will be a teaching tool that enhances the student and faculty experience and advances knowledge in the fields of information technology engineering and green building practices.

"With advanced energy and information technologies in place, Rice Hall will be a key step toward the goal of creating net-zero energy, high-performance buildings," Rosen said.

— By Zak Richards