The Oregon Convention Center (OCC) in Portland, OR, is more than a showcase for the conferences, fairs, exhibitions, seminars, and banquets that fill up the center’s events calendar for months ahead. It’s also a showcase in and of itself for sustainable design.
According to the convention center’s Green Report, “sustainable practices are at the heart of the Oregon Convention Center’s operation and planning. Through facility design, operational practices, and energy and resource conservation programs, the OCC strives to stand as an example for the region and nation of what is achievable with wise resource planning and a conservation ethic.” (From The Green Report, 2002-2003, Oregon Convention Center. Written by Jeffrey A. Blosser, executive director, and Bob Spier, director of operations and OCC Green Team leader.)
After a major expansion in 2003, the convention center is now the largest in the Pacific Northwest, covering nearly 1 million square feet - nearly double its original size - on an 18-acre campus. In November 2004, the center expansion (350,000 square feet) received LEED™ certification under the U.S. Green Building Council’s new LEED for Existing Buildings rating system.
According to Bob Spier, director of the convention center’s operations department, the entire expansion project was undertaken with LEED certification in mind. That meant not just energy efficiency, but indoor air quality, recycling programs, exterior maintenance, and interior cleaning.
In addition to being green, the OCC has set another example by demonstrating that sustainable design does not have to cost more. The convention center was able to save over $300,000 on the renovation’s HVAC system with the installation of McQuay Vision™ indoor air-handling units. These custom-modular units can meet specifications for individual projects, but without the cost of custom units. In addition, the Vision units’ energy performance and sound attenuation helped the Center to achieve its sustainable design goals.
Modular Design Reduces Manufacturing, Shipping Costs
While the original HVAC design for the expansion met the OCC’s requirements, it was over budget. The convention center turned to McKinstry Co., a leading West Coast design/build mechanical contracting firm, where a team led by Bill Goerlich, senior engineer, made some important changes. Goerlich worked with Oregon Air Reps, the local McQuay representative, to replace the custom air-handling units that were specified for the job with 23 McQuay Vision air-handling units (AHUs) - reducing the AHU portion of the budget by 21 percent.
More than coming in under budget, the Vision units also helped the convention center to achieve its other priority - that of LEED certification for an existing building. The LEED Green Building Rating System for Existing Buildings, approved in October 2004, is a set of performance standards for the sustainable operation of existing buildings. Like its counterpart, LEED for New Construction, the rating system is a voluntary, consensus-based national standard for developing high-performance, sustainable buildings.
The design team reworked the fittings and streamlined the ductwork, which enabled the McQuay Vision units to use lower-horsepower motors to reduce energy consumption. In part because of this change, the building’s energy efficiency exceeds the Oregon Energy Code (1998) by 30 percent.
Tony Larson, project manager with McKinstry, notes that McQuay Vision units are built from standard modules, which helps keep the cost down. “The modular units are configured at the factory to meet individual design specs,” he said. “In addition, the pieces are constructed so that they are never more than 80 inches long, so they can be shipped sideways on a semi trailer, keeping transportation costs under control.” This is an important factor given that the largest of the air-handlers installed in the OCC has a coil face area of 90 square feet.
The team made additional design changes that allowed the McQuay units to operate more efficiently. For example, they specified low-leak outside air-dampers to help prevent losses and further reduce mechanical cooling. The dampers keep leakage below 1 percent, which translates into significant energy savings. To further increase efficiency, the units use economizer cooling for outside air, which is a code requirement of the state of Oregon. If the outdoor temperature is moderate, as it often is in Portland, OR, then outside air is circulated in the OCC without mechanical cooling.
Working Quietly on the Job
Some 13 of the 23 McQuay units, including the 90-square-foot air-handler, are located directly above the ballroom at the convention center in a large mechanical room. So that operating noise and vibration from the units would not interfere with events in the ballroom, the design specified a noise criteria (NC) level of 35, approximately equivalent to 35 decibels. The Vision units are installed on large concrete bases with Neoprene vibration-isolation material. Similarly, custom sound traps and vibration-isolation features were added to a smaller unit located directly above the executive offices.
“The McQuay units have operated flawlessly,” said Spier. “They meet all our energy conservation requirements for the LEED-EB program; they maintain the desired temperature in the building; we can program them in the manner we want; and maintenance has been routine.”
A Worthy Showplace for Portland
While the McQuay Vision air-handling units helped the OCC meet its budget as well as LEED requirements for the expansion, the McQuay chiller plant at the center will soon contribute to the center’s overall certification. Installed in 1990, the four centrifugal chillers will be retrofitted to use R-134a refrigerant, which has no ozone depletion or phase-out schedule. Further, variable frequency drives will be installed on the chillers (they already are on the air-handling units), helping the entire convention center conserve electrical energy and qualify for LEED-EB.
Portland, OR, already well-known for its livability, progressive land-use planning, and leadership in the green building movement, can point to the convention center as an example of its quality of life and leadership.
For more information on the Oregon Convention Center, visit (www.oregoncc.org). To learn more about the LEED Green Building Rating System, visit the U.S. Green Building Council’s website at (www.usgbc.org). For more information on McQuay, visit (www.mcquay.com).