When most people think energy saving, they probably think of all the devices that we’ve been hearing about for years: LEDs, occupancy sensors, timers, solar panels, etc. Except for improved equipment, not much has been done to enhance the efficiency of basic mechanical systems. And, you can only take advantage of newer, more efficient equipment with an expensive system replacement or upgrade.
However, a new process has been developed allowing you to optimize, customize and economize on the existing mechanical systems that currently heat or cool your office space.
Most of us know the facility manager’s perpetual headache: accommodating occupants in a building where some are hot and some are cold—at the same time. The boss in the corner office sets the thermostat for his comfort and the remaining office occupants live with what the system gives them. Space heaters pop up under desks. The facility managers are asked, “Can anything can be done?”
Technology now exists to micro-zone every office space in a multi-zone facility. Each space could have its own temperature setting with its own custom schedule. People who are cold can turn their heat up locally. People who are warm can cool just their office. For a facility manager, hot-cold calls disappear; portable space heaters disappear; manpower is saved.
Micro-zoning controls the forced air drop(s) in each office individually using an inflatable pneumatic bladder. Inflate the bladder to stop the air flow; deflate the bladder to allow hot or cold conditioned air to flow into the room. A small control processor monitors a wireless sensor in each space. The processor can then signal a valve control box to pressurize or pull air out of the bladder inflating or deflating just those bladders necessary to maintain customized temperature set points for each space.
With a simple method of sensing temperature and controlling air flow, the control processor can be custom programmed, creating unique schedules for every space. During the heating season, an office may be scheduled from 7AM to 4PM for 70 degrees of heating. A storage or copy rooms, typically unoccupied, may be scheduled for only 60 degrees during heating season and 80 degrees during cooling season. A completely unoccupied stairwell may be scheduled for 50 degrees during heating season and 80 degrees during cooling season.
For a part-time employee who only works in the morning, you could schedule that space from 8 AM to 12 PM. For employees who work out of the office at various times, there is no reason to condition their empty office. Installing a smart sensor allows them to tell the controller that the office will be vacant (and off-schedule) until they return—with a simple press of a button on their office smart sensor. The system links to the office wi-fi and can be accessed remotely via the Internet for easy access and programming.
Economically, the system minimizes the expense of electricity or natural gas that powers the cooling and heating equipment. With programmed control, if a space needs a temperature adjustment only that space gets airflow. With a reduced cooling or heating requirement, the roof top unit cycles on for a shorter period, satisfies that space, then shuts off. If sensors detect spaces that are both over and under temperature at the same time, the system will circulate air between only those areas to balance the temperatures without ever turning on the heating or cooling functions in the roof top unit.
The best part is no expensive re-fit or new construction is required. The system can be installed in an existing office in just a day or two. Facility managers and office managers are excited to hear that many comfort issues can be resolved with this system. Finance managers will be interested to know how they can be saving money.
Paul Maloney, P.E., is vice president of LJS Facilities Experts (LJS Fac/X), a division of LJS Electric, specializing in energy projects, facility engineering and equipment maintenance.