by Kevin Callahan
In the same way today’s mobile phones have capabilities far beyond traditional telephones, modern building automation systems (BAS) have added many benefits transcending their original roots in heating and cooling control.
Today’s BAS help facility professionals obtain greater efficiencies from numerous building systems, including:
- lighting;
- security/access control;
- fire and life safety;
- elevators and escalators;
- irrigation; and
- HVAC.
An appropriately equipped BAS can also meet specialized needs such as emergency and critical systems monitoring in hospitals, and tenant billing for leased spaces in office buildings.
With rising energy costs, an increasing number of building owners and operators are including BAS in new buildings, as well as in retrofits. More than half of U.S. buildings larger than 9290 m2 (100,000 sf) have a BAS installed.1 The market is forecast to grow between seven and nine percent from 2014 through 2017, for a net growth of more than 40 percent above the 2012 level, according to researchers at IHS Technology. A key driver of this “/>growth is a projected eight percent annual increase in retail electricity prices through 2020.2
BAS benefits
Automation can reduce a building’s total energy consumption between five and 15 percent annually because of more efficient control of various building systems. Savings can surpass 30 percent annually in older or poorly maintained buildings. Additionally, a BAS can help reduce building maintenance costs by alerting facility managers when equipment is operating outside of specifications and therefore might be at risk of failure.3
The facilities management and planning department at Boston University outlines these and other BAS benefits as follows:
- control and diagnose what is going on in buildings;
- create a graphic representation of building settings;
- see and fix programmatic problems quickly;
- generate reports usable by management for tracking energy consumption and the operational status;
- schedule and control temperature settings for increased energy savings; and
- collect and store data on energy consumption over long periods.4
Project examples
From commercial offices and government buildings, to schools and hospitals, energy saving benefits can be achieved in virtually every type of project.
Commercial offices
Seattle’s Columbia Center is the tallest building in the Pacific Northwest, with 76 stories and 142,900 m2 (1,538,000 sf) of total floor area. A BAS integrates all the building’s HVAC systems—including 2200 heat pumps, ventilation and exhaust fans, boilers, heat exchangers, cooling towers, and circulation pumps.
The building is one of the city’s largest electricity-consumers, using approximately 111,600,000 megajoules (31,000 megawatt hours) annually. However, with an energy-efficient BAS, it consumes only about 13 percent more electricity than the next highest building electricity consumer in the city, despite having 50 percent more floor area.
Government buildings
In 2009, the state of California opened a new central utility plant in Sacramento to heat and cool many office buildings throughout the city. The 7246-m2 (78,000-sf) facility supplies chilled water and steam to 23 buildings that total 510,967 m2 (5,500,000 sf) of space. One BAS monitors and controls the central utility plant, while another BAS serves the 23 buildings. The BAS for the chiller plant enables it to operate at about half the energy use of a traditional chiller plant.
K–12 schools
At Irvington High School in Fremont, California, the local school district installed a BAS as part of a set of energy-saving actions that reduced the school’s energy consumption by approximately one-third, which equates to annual savings of about $10,000. Much of the savings result from data provided by the BAS, which allows the district to shed energy loads under a peak pricing program offered by Pacific Gas and Electric (PG&E).
Universities
Eastern Connecticut State University in Willimantic installed a BAS in the Windham Street Apartments—a 30-year old, nine-story residence hall housing 224 students. The BAS reduced the building’s annual electricity consumption by 234,000 megajoules (65 megawatt hours), for a 12 percent energy cost savings. The university achieved these savings despite also adding cooling to the building, when previously it only had heating.
Hospitals
As part of a facility expansion and upgrade project, New York University Medical Center in Manhattan retrofitted outdated building controls in 13 buildings totaling 278,710 m2 (3,000,000 sf). The new BAS enables staff to manage the campus and outlying facilities through a single system, for better energy efficiency. Additionally, trend logs generated by the system illustrate how closely actual room temperatures match the set point, which allow staff to closely control the environment for patient comfort, health, and safety.
