Wireless Controls: Improving Performance and Cutting Costs
Property owners seeking ways to reduce operating costs can achieve this goal via energy upgrades. Often through State programs like Pay for Performance, we can upgrade boilers, domestic hot water heaters and chillers, to name a few, with high efficiency units in order to obtain large (15% or greater) annual energy savings. In most cases, these improvements are necessary, regardless of boiler age and efficiency, however, if a system isn’t properly controlled, a property will be wasting money.
Have you ever seen a window open in an apartment in the middle of the winter? Odds are, this isn’t a resident attempting to bring on an early spring, but instead is a classic case of a poorly controlled building.
There are many control strategies that can be implemented in order to save energy in a multi-family property. Some of these improvements are invasive and costly. Wireless controls offer an attractive solution to avoid long paybacks while optimizing building operation both in common areas and in individual apartments.
Certain states have passed legislation requiring building owners to conduct energy benchmarking and assessments. Closest to home, NYC Local Laws 84, 85, 87, and 88 do just that. Prior to these Local Laws going into effect, NYSERDA had conducted studies to research the benefits of installing sub-meters in master-metered buildings. Through these studies, *NYSERDA discovered that overall building energy consumption could be reduced by up to 25%.
Major savings can be realized in central heating and cooling plants through the use of wireless data monitors at prime locations throughout a building. A primitive example of this control schematic would be to install a temperature monitor at the furthest point in the boiler loop. When the temperature requirement is met at the furthest point, a notification would be sent to the boiler to alert it that all zones have sufficient heat, allowing the boiler to unload. This is a very simple example. Wireless controls would allow for a more sophisticated array in which zones, individual apartments, could close when they have sufficient heat, allowing for hot water to be sent instead to zones as needed.
Typically, multi-family boiler systems are controlled based on outdoor temperatures. They do not have zone or apartment control. Replacing boiler controls with a wireless system would allow for heat to be supplied based on the needs of the occupied space, eliminating the issue to open a window in the wintertime because an apartment is too hot. Zone valves and apartment supply water temperatures could be centrally controlled using space temperature data. Utilizing these wireless control systems allow for adaptive and intelligent reset and night setback approaches. This all works to more closely maintain space temperatures at required set points, thereby reducing overall heating costs.
Beyond providing energy savings by properly managing where heating or cooling is sent, large energy savings could be achieved through behavioral modification; i.e., educating residents of energy conservation practices. Wireless controls could allow the building owner to set limits on temperature set points throughout the building. Another heating example would be where a building owner could gradually reduce temperature set points throughout all apartments during unoccupied hours (working hours). Strategically, the owner could survey residents to see if there are any deficiencies in temperature set points and adjust them over time. Each individual apartment could have limits set to match their specific needs.
Alternatively, a website could be set up to show individual tenants just how they consume energy in the apartment. This would potentially allow the community to work together to reduce overall energy consumption. This shouldn’t be viewed as a way to penalize residents, since allowing each resident to access their individual consumption may help change behavior towards becoming a more responsible (or educated) energy consumer.
The more intelligent control strategies create an adaptive system, meaning the system can “learn” the behavior and needs of the complex and adjust accordingly.
Wireless controls not only reduce energy consumption, they assist maintenance personnel with being proactive with major equipment. Wireless controls have the ability to collect all sorts of various data and send it directly to a central location, or even off-site, allowing for 24/7 monitoring. Wireless control systems offer a broader level of monitoring by automatically notifying maintenance personnel when there is a problem with a given system.
Wireless sensors could be used to provide vibration, heat, or noise readings on major energy consuming equipment, alerting maintenance personnel of an imminent failure. Maintenance could also then remotely shut down the equipment in order to prevent further damage. Wireless systems can self-diagnose issues and can detect a poor signal from the controller and send out an alert.
Additionally, wireless controls would help building owners monitor exactly how energy is consumed, which would allow them to make modifications towards reducing consumption without necessarily having to replace equipment. These systems could even be programmed to record data in order to provide management with hard data to assist in making a decision to replace or service a piece of equipment before it fails.
Simply stated, temperature sensors located remotely throughout a building would provide valuable operational savings by allowing building-wide temperature monitoring from a central location by a building’s staff. They would be able to fine tune a system without having to frequently walk the facility.
The primary focus of an apartment community is resident comfort. As a result, traditional building management systems were not typically designed to monitor equipment reliability or performance. Wireless technology can provide valuable real-time information that would not only improve resident comfort, but also dramatically improve building performance.
In recent years, one of the largest barriers to entry for hard-wired energy management systems was cost, with the largest portion coming from labor and installation. Wireless control systems can greatly reduce these costs. Since wireless controls can be installed for a fraction of the labor and installation costs, the savings they offer make the payback highly competitive.
Another benefit to a wireless control system is that when a complete remodel of an apartment complex is not viable, a smart control system allows for targeted upgrades that could be incorporated overtime, all the while reducing operating costs and increasing annual savings for future improvements.
Not all buildings can utilize wireless controls. In some settings it may make more sense to go with a wired modern control system. However, wireless controls can be the most cost effective, least invasive solution for a property. Rarely will this be the only solution for a property, but it’s a great starting point.
Peter Arvay, EIT, CEM is a Project Manager with CoolSys Energy Design and has over four years combined experience leading energy audits and generating energy simulations for a wide range of commercial and industrial clients. He is an Engineer-in-Training (EIT) and a Certified Energy Manager (CEM). He currently leads the P4P energy modeling and incentive programs for CoolSys Energy Design and has extensive knowledge with various State and Federal energy rebate and incentive programs. For more information on state Pay for Performance Programs, please visit (http://www.njcleanenergy.com/commercial-industrial/programs/pay-performance) or please contact (firstname.lastname@example.org or at 609-751-9655
“When the temperature requirement is met at the furthest point, a notification would be sent to the boiler to alert it that all zones have sufficient heat, allowing the boiler to unload.”