Most facilities have a hidden source of cash within their walls. People working in the energy-reduction field know that usually at least a 10 percent savings in energy can be achieved with a payback measured in less than two years, and often right in next month’s utility bill. Some facilities have achieved more than 50 percent savings, while others strive for the net-zero goal. Not only is this a benefit to the bottom line; it also contributes to a greener environment. And it’s just a few steps away.
1. What, where, how and why
A walkthrough site audit will give you an overall lay of the land, and you readily will find things—such as lights on in unoccupied rooms, doors or other openings between conditioned and unconditioned air zones open (including missing ceiling tiles), conflicting tempera-ture requirements (people with portable heaters on at their feet while AC is set too low), and so on—that can be quickly remedied. Es-tablish an accurate energy baseline for the facility by connecting an energy-monitoring instrument at the service entrance for at least one business cycle, which is how long it takes the process at the facility to repeat itself. If possible, conduct the audits in the summer and winter when heating, ventilating and air conditioning (HVAC) is trying to keep up with the outside environment. That will provide a more complete energy-usage profile. With this data, sit down with the facility operation managers to determine what equipment is caus-ing the peaks in demand. Then the energy monitor can be placed at the point-of-utilization for the largest consumers of electricity to determine if they are operating efficiently.
2. Develop short-term goals and plan
Match up the results from your energy audit with last year’s energy bills. Sit down with a group of interested people from each func-tional area of the company to brainstorm ways to reduce costs without impacting productivity and quality. From this group will emerge a project champion, someone who will be the central focus in charge of organizing, checking progress, redirecting the effort when it drifts off-course and inspiring more efforts.
Look closely at the energy bills, as it is not just what energy is used, but when and how. The demand charge often can be a larger cost than the energy portion. For example, during one 15-minute interval in the summer, the HVAC was running at full capacity, all the lights were on, and several large loads started. Now the customer is paying for that each month, even when the monthly demand is much lower. Preventing a new peak demand from occurring is like buying an annuity. It pays off in the future.
3. Harvest the low-hanging fruit
Look for low-cost solutions with a payback of two years or less. There usually is a significant list of easy items to fix that pay immediate results. Considering more than half of the electricity in the United States is consumed by motors, properly maintaining motors, damp-ers and other equipment related to the HVAC system, as well as motors used in production and the operation of a plant, will provide instant payback. Replace air filters regularly. Cleaning light fixtures (luminaires) and replacing old bulbs with newer technology will make things bright enough to turn off some and still maintain adequate lighting for productivity. Where practical, install motion-sensor or occupancy-sensor switches to turn off lights and equipment when they are not in use.
4. Re-audit to ensure things improve (and that none get worse)
Some well-intentioned solutions may not work as advertised or may be causing a conflict with something else in the facility, such as in-creasing harmonic currents that result in higher transformer losses. Communicate the results to others, and more people will get in-volved in helping, as the bottom line affects everyone’s paycheck. The money saved from the first step can be put back into the budget to fund improvements that might require higher initial cash outlays with longer term paybacks, such as replacing motors due for rewind or in variable-demand-use roles (such as HVAC) with adjustable speed drives. Exit signs and 24/7 lighting can be replaced with LED-based lighting. Meet with a utility representative to learn about offerings such as demand-side management, load curtailment programs or al-ternative energy-source solutions that can be implemented.
5. Go back to step 1
These programs often are compared to archeological digs. The first layer is easy to uncover, and a lot of interesting things are found. To keep digging deeper might require a bit more work, but the rewards are comparable and sometimes better. Net-zero-energy buildings may be expensive now, but getting a quarter of the way there isn’t. Along the way, perhaps a new champion will step forward with a fresh per-spective and a whole new set of savings opportunities will materialize.
BINGHAM, a contributing editor for power quality, can be reached at 732.287.3680.