4 FM quick reads on Building automation
1. Five Factors to Consider Before Replacing or Expanding a Building Automation System
Today's tip from comes from James Piper, contributing editor for Building Operating Management: Consider these five factors when considering whether to expand or replace a building automation system.
1. Evolution in the building automation field has brought changes not only in what the systems can accomplish but also in how they accomplish it. While this has led to increased system performance at a lower cost, it has also made many older systems obsolete. Many of those systems simply are not compatible with the architecture employed in new system designs. As a result, if any changes are made to the existing system, they must be made using components compatible with that system.
2. Manufacturers promote the new systems while phasing out the older ones. While most will continue to support older systems for a period of time, there comes a point when it is no longer economically feasible for them to do so. When this occurs, replacement and expansion parts become difficult or impossible to find. Service support may no longer be available.
3. Some limitations of existing systems may be the result of the way the system has been operated and maintained. Some system owners fail to keep up with upgrades to the system's software, firmware and hardware. These upgrades often serve to correct past operating problems as well as to offer system enhancements. Without them, system performance will suffer, particularly in comparison to new and upgraded systems.
4. Talk to those who operate, maintain, and work with the existing systems to identify strengths and the weaknesses. The operating staff can also help to determine if the number of problems is remaining constant, increasing or decreasing.
5. Finally, determine how well the existing system is being maintained. What might be perceived as a system limitation may be the result of a lack of proper maintenance. If the existing system is not being properly maintained, how can management ensure that the new system will not suffer the same consequences?
Five Rules of Thumb Can Aid Decision to Replace or Upgrade BAS
Today's tip from comes from James Piper, contributing editor for Building Operating Management: Use these five rules of thumb to evaluate whether to replace or expand the building automation system.
Building automation systems, like all other building components, have a finite life. As they age, they become more difficult and expensive to keep operating. Components for replacement or expansion become harder to find. And frequently, manufactures cut off support to older systems, rendering them obsolete. When one factors in advances in system capabilities, facility executives face a challenging question: Is it better to expand an existing system or to replace it?
Several rules of thumb can help when choosing between expanding the existing system or replacing it:
1. If the existing system is still supported by the manufacturer, has the capability of performing all of the functions needed and has sufficient capacity to expand by 50 percent, consider expanding rather than replacing.
2. If the performance of the existing system is an issue, and the software and firmware have not been upgraded to their latest versions, investigate how an upgrade would improve performance, how much it would cost, and how those costs compare to the cost of replacement.
3. If the lack of proper maintenance has led to the situation where replacement is a consideration, address the maintenance issue first. If maintenance will restore the existing system, it may not be necessary to replace it, but if the system is replaced without addressing maintenance, the cycle will repeat itself.
4. If the existing system is an orphan that cannot be upgraded, replacement most likely will be the best option.
5. Compare the cost of upgrading the existing system to the cost of replacing it. If the existing system is more than ten years old, and the replacement costs is less than 125 percent of the cost to upgrade or expand, replace the system.
Free Handbook Can Help With Tracking, Improving Building Performance
Today's tip from Building Operating Management: A new, free handbook can help facility managers track and improve building performance for energy and building systems.
The Building Performance Handbook offers advice on tools that can be used to monitor the energy and system performance of buildings. Performance tracking is aimed at continuous improvement of building systems and operations. There are four elements to performance tracking:
• Collect data and track the performance of the HVAC and lighting systems, plus energy use data.
• Identify performance problems.
• Diagnose problems and identify solutions.
• Fix problems and verify results.
To help facility managers build a business case, the handbook identifies a range of benefits from performance tracking, including enhanced occupant satisfaction, reduced energy costs and increased property values.
There are three basic tools for performance tracking: energy benchmarking, utility bill analysis and the building automation system, which can help to collect and analyze data, identify and solve problems, and track results. In addition, the handbook identifies advanced tools for energy and system tracking that include energy information systems, building automation systems, and fault detection and diagnostic tools. But none of those tools can be most effective unless the appropriate management framework is in place. The handbook identifies six elements of an effective management framework:
1. Allocate resources, including making time for staff to analyze and act on performance data and providing training.
2. Identify a team, which should include both top management and operating staff, along with a champion.
3. Set specific performance goals.
4. To motivate staff, consider incentives ranging from creating recognition programs to linking bonuses to energy performance.
5. Ensure accountability with well defined reporting policies.
6. Include performance tracking goals in contracts.
The handbook was written by PECI, a non-profit organization devoted to energy efficiency, and funded by the California Commissioning Collaborative.
Basic Ways That Building Control Systems Can Help Save Energy
Today's tip from Building Operating Management: Building control systems offer a variety of basic energy saving capabilities.
There are a variety of energy saving strategies built into the energy management function of the current generation of controls. The energy savings from these functions can help justify the cost of new or upgraded energy management system.
One basic function is automatic stop-start. While this saves energy by turning equipment off at scheduled times, a more powerful strategy can be more effective. Known as stop-start optimization, this approach goes beyond a schedule by considering indoor and outdoor temperature to decide when a piece of HVAC equipment should be started and stopped.
Another important function is the system's ability to change set points automatically in response to changing conditions inside or outside of the building. A simple example is the air-side economizer cycle. When the temperature and humidity of outdoor air are appropriate, that outdoor air can be brought into a building without being heated or cooled.
A control system can also optimize the operation of chillers, boilers, cooling towers and pumps, adjusting equipment operation on the basis of loads.
A sophisticated strategy is called load shedding. That strategy adjusts HVAC equipment operation to reduce energy use. This may be done when a building is in danger of setting a new demand peak load, or it may be initiated in response to a signal from a utility.
As useful as these and other control strategies are, they can't be taken for granted. Over time, for example, start-stop schedules may cease to reflect actual building operations, possibly because of changes to the occupancy of a building. What's more, control strategies are all too often overridden by maintenance and operations staff. Those overrides are frequently intended to solve a problem, but the long term effect is often energy waste.