By Kenneth Wacks, Ph.D.
Published in the June 2006 issue of Today’s Facility Manager
In the late 1800s, the leading edge technology was a thermostat. This revolutionary device allowed building occupants to take control of temperatures themselves, thus replacing the tradition of banging on the pipes to alert the superintendent in the basement. Times have changed drastically since then.
More than just a device to control temperature, today’s technologies for building automation create facilities where the environment seamlessly improves the comfort and productivity of the occupants. This technology can also provide services to the facility manager that may have a positive impact on the organization’s overall profits.
In modern buildings, many automated systems already exist—HVAC, lighting, fire/life safety, security, energy distribution, and any other type of equipment that operates on its own. And yet, these devices typically work independently, despite the fact that significant benefits can be achieved by coordinating control among them.
For instance, HVAC and lighting might be linked to building occupancy sensors to avoid cooling and lighting unoccupied spaces. In addition, productivity may be increased and turnover decreased by providing individualized lighting and HVAC control within offices.
Unfortunately, since many of these building systems are installed by different vendors, they are operated from separate control panels and have a difficult time communicating with each other. In order to be considered “intelligent,” a building must be able to coordinate and monitor at least a few of these subsystems concurrently. Building monitoring might include sensors embedded in the materials within the building structure to detect leaks, corrosion, etc. Subsystems for energy metering and water management may be added later.
Benefits Of A Baseline
The integration of these subsystems to form an interoperable building control system is the hallmark of an intelligent building. Interconnection allows for monitoring by way of a common communications network that links to a central control panel.
One of the benefits of networked building automation is that it extends controls to facility professionals, members of their staff, and even outside individuals (consultants, engineering experts, etc.) who have been granted proper clearance. Furthermore, networked controls would allow reconfiguration of these subsystems to accommodate office layout changes whenever businesses undergo reorganization.
Because of their complex nature, interoperable building systems (and the associated networking approaches) should be selected during the design phase of a building. While facility managers are part of the decision making team, it is also important to include the project leader and managers or representatives from key departments.
If a team approach is not practical, the burden falls on the designers to consider the needs of various categories of building users. Since these people will operate and occupy the building, it is important for the system designers to be aware of their audience. The consultants and contractors must understand the daily activities of the ultimate users, including building engineers, service technicians, facility operators/building managers, employees, and visitors.
The criteria for evaluating intelligent building technologies can be divided into three broad groups (see Table 1):
- Group 1: Subsystem operation without a network connection (applies to individual subsystems);
- Group 2: Subsystem operation with a building automation network (these deal with subsystems connected by a network); and
- Group 3: Subsystem business considerations (non-technical considerations that have long-term consequences on costs, convenience, and flexibility for operations).
A building automation subsystem (BAS) network includes sensors, actuators, user interfaces, and controllers. Each device on the network is called a node.
Stand alone specifics. BAS for lighting, HVAC, life safety, and other essential operations should be designed to operate autonomously when not networked to other subsystems. This helps promote reliable and fail safe building performance, especially since some functions may be lost if or when the network fails. Essential building services can be better preserved when each subsystem is operating independently.
The features of each subsystem in essential operations are generally tailored to the building design. Thus, considerable customization and the issuance of RFPs (Requests for Proposals) to suppliers may be required; these are not generally systems that can be purchased off the shelf.
The building designer should specify the precise needs of the building in terms of performance specifications. Additionally, the system designer must work with the equipment maker to ensure proper operation in the expected environment of the building.
Some other issues to be considered for each BAS include failure and emergency operation specifications. Building operators who do not contract out support and maintenance need to be prepared to address issues of BAS configuration, upgrades, monitoring, testing, and other operational necessities.
BAS operation with a network. The challenge of interconnecting subsystems is to ensure they can interoperate efficiently and effectively. This implies that they all conform to the same communications specifications.
However, most BASs use proprietary communications methods (such as BACnet and LonWorks). Fortunately, there is a growing trend to conform to open, public standards—a trend that will promote interoperability.
When dealing with BAS equipment that has been networked, users must be able to control authorization and access. Additional system management criteria may include commissioning the network during construction and employee move in, upgrades, maintenance, and usage accounting if individual departments are billed for some services.
Business considerations. Information about subsystem manufacturers is important for judging their networking knowledge and willingness to adapt their products to the building environment. The choice of equipment suppliers has important consequences, since they usually provide a long-term maintenance contract following initial installation.
An experienced manufacturer should be able to deal with codes, contractors, developers, and building occupants. The manufacturer should supply documentation for facility managers, equipment installers, operators, maintenance personnel, and employees.
In terms of the business aspects of BAS, facility professionals should keep in mind that costs will extend well beyond equipment. Staff training, licensing, royalties, liability insurance, and other factors should be considered.
Intelligent building technology is evolving as networks and components improve. Building designers and personnel need continual education about these changes. Manufacturers may provide some of this education (or have ties with professional organizations that deliver timely training), but facility professionals should plan to spend in this area if they want to keep their buildings and staff members up to date.
Best Practices To Simplify BAS
Changes have come slowly to the world of building automation, primarily because BASs need thorough testing for long-term deployment. Nevertheless, facility managers, architects, and building engineers should prepare for an increased rate of change. After all, changes in computer technology are extremely rapid, with no slowdown anticipated.
Intelligent buildings are becoming a potential source of revenue for those professionals who have learned the language and seized the opportunities presented by technology. The bottom line is improved building performance, a better working environment, and more productive occupants. These goals not only make for better operations, they make for great business.
Wacks is a management advisor on building systems to companies worldwide who has been a pioneer in establishing the industry. For further information, please visit www.kenwacks.com. Complete copies of The Intelligent Buildings Roadmap and The Best Practices Guide, Evaluating Intelligent Building Technologies are available at no cost from www.caba.org.
© Copyright 2006 Kenneth P. Wacks