Genzyme Corp. is diligent about telling the world its story. Even its new corporate headquarters building in Cambridge, Mass., proclaims the message—that the biotech company makes its money by being kind to life. The 12-story building expresses this message through the automation running quietly behind the scenes. Not only does the automation keep the company’s operating, maintenance and energy costs low, but it also creates a “green,” but functional work environment.
Movable mirrors on the roof direct sunlight inside, and programmable blinds follow the sun during the day and close at night. Monitors even track which windows are open and how much rainwater the building has collected in its reservoir. The automation then supplements these resources with “artificial” sources, such as its interior lights and its heating, ventilating and air-conditioning (HVAC) units.
Although most companies are not quite as green as Genzyme Center in their approach, a growing number are relying on automation to control the climates inside their facilities, contain rising energy costs and enhance productivity. “Over the last five to 10 years, building automation has expanded beyond climate control to include lighting and other forms of energy consumption,” says Mark Liston, director of Schneider Solutions at Schneider Electric North America, Palatine, Ill., a vendor specializing in power, control, automation and energy services.
The backbone of the direct digital control (DDC) system at Genzyme Center is the Andover Continuum control system from TAC, the Boston-based subsidiary of Schneider Electric that specializes in building automation and energy management. The Windows-based system connects to the building’s Ethernet virtual private network, allowing Genzyme to adopt a distributed control strategy.
Lights, temperature sensors and other smart devices plug into controllers on each floor, and each of these controllers are connected to the network. Because the distributed strategy eliminates the need to run a wire from each smart device to the central controller, these decentralized floor controllers significantly reduce the amount of field wiring required. “Open systems like LON, BACnet, and the emerging Ethernet-based Web technologies have given owners the ability to integrate systems together at less cost,” notes Liston. LON and BACnet are popular architecture standards for building automation.
Besides making it economical to compensate for the temperature variations that occur throughout the day, the distributed strategy gives the company the best of both worlds of local and global control. It lets employees adjust the climate and lights to their needs and preferences, yet it ties the controllers together at a master station. So rather than having to go to the different areas in the building to determine their status, one person can view the entire facility from a central location.
The distributed network also made it practical for TAC to integrate parts of the security and safety apparatus into Genzyme’s building automation. The facilities management system, for example, monitors carbon monoxide and carbon dioxide and adjusts the ventilation to keep the concentrations of these gases at appropriately low levels. The system also receives input from a combination of occupancy sensors, surveillance cameras and door controls such as access-card scanners. Using input from these devices, the automation tailors the utilities to actual occupancy, shutting off the lights and turning down the HVAC system automatically when no one is there.
“It could be in meeting rooms that are used only certain times of the day or an entire floor during the off-hours,” explains Liston. “Without controls, there is no way to reduce energy usage based on occupancy or use.” The controls that Genzyme has installed conserve at the appropriate times automatically without management’s having to badger employees to shut the lights off or turn down the heat.
Another benefit of distributed control is that the automation measures and tracks the cost of the utilities that each operating unit consumes. It therefore can allocate the actual cost to each unit. “Accurate energy metrics are critical in driving behavioral changes as part of an overall energy-reduction program,” says Liston. “It’s difficult to motivate people to save energy without giving them a benchmark.” And the conventional method of rolling the cost of utilities into overhead and allocating them by floor space doesn’t do that.
Factory benefits too
The office isn’t the only place where building automation can give the bottom line a nice boost. More manufacturers are using it to reap similar returns in the factory. Not only does good lighting and a comfortable climate affect personal productivity there too, but it also is a crucial control parameter for the processes in certain sectors. In pharmaceuticals, for example, temperature and humidity affect the accuracy of weighing drugs and the formability of powders into pills. Clean, controlled climates are essential for electronics manufacturing too.
Rising energy costs have forced these companies to rethink their climate controls. “In 2005, when oil prices really spiraled out of control, we began monitoring the situation even more closely and investigated ways to curb our energy bills,” says Mark Engman, president of Opto 22, a Temecula, Calif. based manufacturer of remote-monitoring, data-acquisition and other automation hardware. The situation had become urgent last year because the company’s energy costs had jumped by 12 percent in January and 11 percent in February. Forecasts had projected them to jump by 22 percent in June.
The local power company, Southern California Edison, had turned up the heat on large commercial and industrial customers such as Opto 22 that consume more than 500 kilowatthours (kWh) on any given day. If they exceed this threshold even briefly, they are charged a more expensive peak usage rate. Opto 22 was well above that, exceeding 800 kW-h per day routinely.
In response, the company’s engineers applied the same engineering principles that they use to design their products and manufacturing processes. Like most manufacturers today, Opto 22 had already wired its factory with Ethernet. Unlike most, however, it had taken the extra step of automating the lights.
In an upgrade, it had linked them to controllers with one of its own products, its Snap Ethernet I/O (input/output). Consequently, after studying the lights and determining which ones really needed to be on and which oes could be turned off, Project Engineer Kelly Downey and Research & Development Engineer Tommy Leung were able to divide the company into sectors and devise a control strategy for each. They programmed the strategies into the Snap Ethernet systems and developed the necessary display screens. Then they began experimenting with using more sunlight to shut off a third of the overhead fluorescent lights.
Sharing HVAC data
Meanwhile, the project team also began upgrading the HVAC controls in both the corporate offices and factory. It replaced all of the Opto 22 serial-based Mistic controllers with the company’s Ethernet-based Snap PAC-S1 programmable automation controllers. Although the old controllers were still working correctly, the newer, more powerful PACs not only would offer better control over the HVAC system, but also streamline data collection and analysis. “Ethernet connectivity makes it easier to share the data across the company,” says Downey.
The ability to collect data proved to be fruitful. The team, for example, was able to identify and repair a number of broken fan belts, burned-up motors, and other malfunctions that had been causing inefficiencies. It also discovered a big inefficiency in the valves that controlled water-glycol mixture for the air-conditioning. When the servo-driven valves work correctly, cooling occurs faster, and the fans need not run as long. The team was able to generate a substantial savings by replacing broken servo motors and rethinking the control loop to make it simpler, more efficient and easier on the valves. Another fruit was the ability to turn the fans off periodically during the day. Many of the 30 or so fans that blow cooled air throughout the corporate offices had been operating all day long. Based on the analysis, the engineering team was able to divide the office space into zones and write control algorithms that turn the fans on only long enough to cool their assigned areas to their predefined set points.
They devised a slightly different scheme for the factory, which uses four very large HVAC units, as well as a few smaller ones. As was the case for the fans on the office side of the facility, the blowers on the factory side had been running constantly. The new scheme called for only one of these large units, as well as a small unit, to be operating at any time. Each set operates for a short time in a round-robin sequence.
The next phase of the project consisted of automating the dampers. Temperatures in Temecula can be in the forties and fifties in the early morning hours, but can rise rapidly into the nineties by noon. So probes connected to analog input modules on the I/O rack periodically measure the outside temperature. “If the temperature is below a certain threshold, the Snap PAC opens the dampers, flushing out the old stale air in the building and giving us a running start on cooling the facility,” says Leung.
The results have been remarkable. In the first four work weeks of July last year, Opto 22 consumed between 575 and 650 kW-hof power. This figure is down considerably from the 660-to-871 kW-h of the previous year. August saw even greater reductions. “In spite of almost monthly double-digit price increases last year, we’ve been able to keep our overall bill at approximately the same level,” says Engman.
Ethernet for utilities
Rising energy costs are not the only force changing the economics of automating building services. The migration of Ethernet from offices onto the factory floor has had a big impact over the last decade. “We can make use of the existing Ethernet network,” says James Davis, senior applications engineer at Opto 22. “And if one’s not in place, there are many wireless solutions.” The ability either to plug into a standard network or to broadcast to a receiver can eliminate the expense of running wires from each device to a control panel.
Davis also points out that open systems make the spectrum of robust tools already in place for controlling and monitoring process equipment available for automating buildings. Open systems played a role in the University of Cincinnati’s decision to replace the distributed controls system that it had been using in its utility plants. Besides providing the steam, chilled water and electricity for a 420-acre university with 34,000 students, the plants also supply the same services to research facilities and six hospitals.
“When you’re serving universities and hospitals, reliability is critical,” says Joe Harrell, director of the university’s utilities. But his concerns don’t end there. “We are a miniutility company. So in addition to being reliable, we also want to keep our costs low, as well as remain environmentally friendly.” Not only were theagingcontrolscausingsomereliability problems, but they also bound the university to the supplier for service and equipment.
For these reasons, the facilities management department decided to install an open controls system capable of being maintained by the university and of exploiting more robust, industrial-grade technology. Fosdick and Hilmer, a Cincinnati-based engineering and systems integration firm, built the control system around FactorySuite automation software from Wonderware, a Lake Forest, Calif. based unit of Invensys Systems Inc.
By means of fiber-optic cable, a high-speed Ethernet network now links the 11 programmable logic controllers (PLCs), nine process automation controllers and other instrumentation that oversee the equipment and storage tanks. Also on the network are nine workstations running Wonderware’s InTouch human-machine interface (HMI) software. Wonderware’s IndustrialSQL Server historian collects demand and process data in real time and stores them in archives for trend analyses and optimization.
Energy optimization software tracks the demand across 60 buildings and directs the delivery of services based on equipment availability and current fuel prices. “The dynamics vary almost every day,” explains Harrell. “We can buy electricity from the [public] utility, or we can produce it ourselves with natural gas or fuel oil.”
Not only does the software tell the operators what is happening in the processes, which gives them greater control to enhance their performance, but it also calculates the optimum mix of resources and fuels. So it helps the university’s miniature utility company satisfy demand at the lowest possible cost.
For more information, search keywords “energy savings” and “building automation” at www.automationworld.com.