In The News

Originally published in July 2007 issue of ASHRAE Journal

Can a campus of 10 office buildings achieve true energy efficiency?

Arguably, there is currently no hotter topic in property management than finding ways to reduce energy costs. And if it isn’t the number one focus, most would agree that it should be. Consider the old saying, “a penny saved is a penny earned.” Now multiply that by a few hundred million and you’ll see what’s at stake.

Building engineers share a high appreciation for a building automation system that can literally pay for itself by reducing energy usage, maintenance requirements, and tenant calls. With an easy to install system that uses intuitive programming, a Class A facility can become more efficient than ever thought possible. But what about when the situation is applied to a business campus of ten office buildings ranging between 5 and 31 floors each? Does a solution even exist?

Such is the case for Greenway Plaza in Houston, Texas. Greenway Plaza is a 4.3million sq foot, ten building campus environment that includes both office and retail spaces. The network of structures are cooled and heated from a single central plant. Complicating this are third party properties connected to that system which must not be interrupted. The central plant used a staggered-start system to prevent interruptions, but this method was both difficult to use and time consuming. Incorporating ten individual buildings on a single HVAC automation system clearly appeared to be an enormous task—and it was for some time until Kevin Saul, Senior Chief Engineer of Greenway Plaza, researched several BAS options and invested in Computrols Building Automation Systems.

Computrols, Inc. (www.computrols.com) is headquartered in New Orleans, Louisiana with domestic and international offices and a global authorized dealer network. Computrols designs, manufactures, and services simple to use state-of-the-art building automation hardware and software that apply technology toward the goal of energy efficiency. All hardware is manufactured exclusively in the U.S. and every controller has received the government’s Energy Star Rating. Over the past 24 years, Computrols has established a solid reputation as a leader in building automation systems, one that made sense when it came to providing a tailor-made solution for Greenway Plaza.

The new system would include two CBAS Servers, two CBAS Web Servers, multiple Graphic Workstations, both 32x and 64x Computrols DDC Controllers, Computrols VAV Controllers, programmable thermostats, and N2 Protocol Interfacing on variable frequency drives, pumps, and meters. This interfacing would allow changes in fan speed based on airflow needs furthering the energy efficiency of the system.

Computrols’ CBAS software applied an Optimal Start programming feature. Now each floor is self-regulating. This replaced the hard start technique which required more operation and supervision time. With Optimal Start, start up time has been dramatically reduced by hours.

On the hardware end, the new Computrols system has also eliminated most pneumatic controls and human error that occurred via local thermostat controls. The system now actually maintains the temperature setpoints, something the old system did not.

Then there’s the positive trickle-down effect that comes with a more efficient system: reduced tenant calls. Since the installation of the Computrols system, calls coming in are resolved the first time and the number of calls continues to drop. This translates into more savings for building management and more content building occupants.

Impressions from Kenneth Bracewell, Chief Engineer of Greenway Plaza are, in his words, “positive as can be.” Mr. Bracewell relates that the CBAS logic programming is much easier than other systems he has used. “With 25 years of field experience, I can trim energy costs and still deliver a Class A environment that our customer base has come to expect.”

So far, significant energy cost savings are already being seen. It’s estimated that at its current trend, Greenway Plaza will total an unprecedented $2.1 million reduction in energy costs during the first year and a half of operating with the Computrols building automation system. Going by that estimate, the system will also more than completely pay for itself in that same period of time.

Computrols has been so successful for Greenway Plaza that as expansion of the new system continues, so do the opportunities to expand the Computrols system. One additional building remains left to add and is set for completion in 2008. Single and multi-zone units also continue to be installed. Throughout the system, pneumatics are constantly being eliminated and replaced with DDC equipment.

Asked if he’d recommend a Computrols building automation system, Mr. Bracewell responded, “If a property management company was looking to upgrade to a state of the art web based system with user friendly logic programming, Computrols is definitely at the top of the list.”