NSU turning to geothermal methods to heat and cool Broken Arrow campus buildings

Tuesday, February 4th 2003, 12:00 am

By: News On 6

(TAHLEQUAH, OK) â€“ Aesthetically pleasing with its manicured gardens, flowing fountain and equally attractive buildings, the new campus of Northeastern State University has been called the jewel of Broken Arrow. Serving a record 2,167 undergraduate and graduate students from Tulsa and the surrounding area, the campus was designed to be beautiful, practical and cost efficient. Two Tulsa-based companies, Bates/LZW and Martin Engineering Design, laid the groundwork for the high efficiency campus and together created what has become a benchmark for future projects.

â€œThe architect and engineer did a fantastic job, working together to design these buildings to be not only beautiful and functional, but energy efficient as well,â€ said NSU President Dr. Larry Williams. â€œBuilding this campus was a tremendous opportunity for Northeastern to set new standards in educational facilities.â€
Through a specially-designed geothermal heating, ventilation and cooling system, Northeastern State University - Broken Arrow has saved more than 50 percent in utility costs. This is more than $180,000 in savings per year when compared to the Building Owners and Managers Association (BOMA) 2000 Standard for a campus of its size.

From the Ground Up. When engineers sat down to pen out the heating, ventilation and cooling (HVAC) system for the new Northeastern State University - Broken Arrow campus, they started from the ground up, literally. Working in conjunction with the architecture firm of Bates/LZW and Northeastern officials, Martin Engineering Design offered present-worth comparisons on several systems. After carefully analyzing soil and heat exchange rates from a sample well, relative initial costs, relative operating costs, equipment life and life span comparisons; the decision was clearly the geothermal heat pump system. The thermal well system composite was designed by Bates/LZW and by Martin Engineering Design.

â€œThe simplicity of the geothermal system at NSUBA was instrumental to our project success,â€ said Ed Bates, owner of Bates/LZW. â€œWe were able to not only finish the project ahead of time, but we were also able to come in under budget because construction crews were not delayed by the systemâ€™s installation.â€

Understanding the System. With high utility rates, NSUBAâ€™s system is very cost efficient, at least 25 to 40 percent more efficient than comparable systems. A closed loop system, the geothermal HVAC system uses the earth as the heat transfer medium, employing a slightly treated mixture of water pumped through a continuous loop of sealed polyethylene pipes buried beneath the ground. In winter, the systemâ€™s geoexchange component brings the earthâ€™s natural warmth up to a building, transferring it into each room or zone via a heat pump. In summer, the component works in reverse to provide air conditioning, absorbing the heat from inside a building and transferring it into the cooler earth below. The outdoor portion of the system involves 483 wells (under parking lots) to a depth of 300 feet each with a horizontal matrix of pipes leading to the building(s). Redundancy in the system allows for equipment failures without losing service to the rooms. There is orderly extension of the system designed for future buildings.

High Efficiency. According to BOMA 2000 Standards, annual utility costs (including water) for 225,000 square foot of building space would cost $1.55 per square foot, or $348,750. Based on utility costs (excluding water) from July 2001 to present, Northeastern State University - Broken Arrow averages $12,500 per month. The average water expenditure per month is $1,000 bringing the total utility expenditure per year to $162,000, a more than 50 percent cost savings over the BOMA Standard.

In addition to the tremendous cost efficiency, the system has other very pronounced benefits. The out of sight, out of mind system is quiet with no cooling towers with associated fog, noise and spotting of cars and no unsightly, noisy chillers. The system is also easy and convenient to maintain with equipment modules located in the attic catwalk. Repairs and service can be made without disturbing classes and other use areas.

â€œThis system is a very simplistic solution to high efficiency,â€ said Glenn Martin, owner of Martin Engineering Design. The geothermal heat pump system is simple, concealed and most importantly, it is energy efficient. It says weâ€™re doing our job.â€