4 FM quick reads on BAS
1. Setpoint Changes Can Cause Energy, Other Problems
Energy management systems offer a convenient and reliable way to reduce energy use. But reliable doesn't mean foolproof. Energy management systems don't always deliver the savings they're expected to.
One common problem is that set points are changed without authorization. Often, the person who makes the change is trying to resolve an occupant complaint about a space being too hot or too cold. Overriding a set point may work as a short term fix, but it may lead to longer term problems. For one thing, energy is wasted. For another, it may cause a ripple effect, producing another problem - such as occupant discomfort - as an unintended consequence.
Simply telling staff not to touch set points may not be enough to prevent it from happening. Overriding set points may be a sign of a deeper problem. If the staff doesn't understand why the system is set up the way it is, they are more likely to make changes that might undermine system performance. If that's true, training may solve the problem.
In some cases, the system can be set up to provide levels of access, so that only approved staff have authority change set points.
Building automation and maintenance
I'm Dan Hounsell, editor of Maintenance Solutions magazine. Today's topic is building automation and maintenance. When organizations face tough economic times, maintenance and engineering managers often receive one overriding directive: Cut department costs. But that objective often is a complex task, as managers with Pittsburgh International Airport understand all too well. Fortunately, the airport's decision to upgrade its building automation system, or BAS, has paid dividends that go far beyond the more common benefits of energy efficiency. The airport upgraded its BAS in 2002, just as the airline industry was entering a prolonged financial slump. Managers knew the upgraded system would have to meet cost-cutting objectives and energy-efficiency demands. The arrival of the BAS has translated into benefits that also involve technician productivity and worker efficiency. For example, the BAS streamlines troubleshooting activities by allowing technicians to trend areas to analyze the indoor environment more accurately. "Trending is probably one of the best things we can do," says Len Boehm, an HVAC supervisor. "If we know we have a problem area, or if we know we have an area where we're over-conditioning, we can definitely go into that right away. We're way ahead of everything, instead of being behind it." The BAS also directly affects the way technicians look at long-term equipment performance. The system aids technicians in performing thorough preventive maintenance, ensuring strong performance throughout the equipment's life cycle. "We're checking the zones, we're checking pneumatics, and the (direct digital control) panel's checked,” Boehm says. “Even the air that feeds our pneumatic electronic systems, we're checking that for moisture and oil content." The new BAS not only has helped the maintenance department become more efficient. It also has helped follow through on the goal of lowering utility costs. Says Boehm, "One of the things we can't afford to do is be behind the 8-ball here because we don't have that manpower that we used to have. This system has made it that much easier. I guess you could call it the 12th man."
BAS Has an Important Role with Demand Response
A demand response program is an opportunity for a facility to reduce electricity costs. In a demand response program, a facility gets paid for reducing energy use when asked to do so by a utility. The programs kick in when demand on the grid approaches capacity or when wholesale power prices get very high. There are plenty of ways that a facility can reduce its demand without having a dramatic impact on operations or comfort. The trick is to shave a little energy here and a little there, rather than making larger changes that might have a big impact on building occupants. Enter the building automation system. It's the perfect tool for implementing the small changes that can trim energy use enough to meet demand response goals. For example, the BAS can allow temperatures to rise a degree or two, or dim lights slightly. The number of demand response steps that can be automated through the BAS depends, of course, on which building systems are integrated and how the BAS is programmed. For facilities that have aging building automation systems and that aren't taking advantage of demand response programs, the savings offered by demand response can be one more factor to help justify a BAS upgrade.