In the November 2009 SAM, we touted energy audits and how they can help quickly reduce energy costs. One of the fastest and best places to start is lighting. In the average commercial building, lights account for more than 50 percent of the electrical costs. Two key steps help control costs: reducing the wattage of each fixture, and turning off the lights whenever they are not needed.

The more automatic you can make your lighting controls, the less you have to depend on employees to do that task. Motion sensors are typically used to control lighting in areas without lighting controls and in employee areas. Zone the lighting in these spaces, and you can turn the lights on and off, as appropriate, from one end of the space to the other.

In areas such as restrooms that require the lights to be on during business hours, you can use a dual technology motion sensor that also relies on audible triggers. If there is noise when the infrared sensor would go off, it stays on for another time cycle, and if there is noise right after the sensor goes off, it will turn back on. You can also link the restroom exhaust fan with the motion sensor.

Now, let’s turn to the lights. Lighting is a constant electrical load. Taking a long-term look at lighting upgrades will result in considerable savings. In many cases, older two-lamp T12 fluorescent fixtures can be upgraded to one-lamp T8 fixtures and you get almost as much light—just make sure you clean the reflectors. In nearly every instance, you can use the same tombstones, just install a different ballast and a new T8 lamp. The more fixtures you change, the more the load reduces. Other benefits: T8 lamps typically last longer, and they can be turned on/off without degrading the life of the bulb (as happens with T12 technology).

Another good switch: In larger areas, replace high bay metal halide lights with T5HO linear lamps and get the same amount of light at half the wattage. And, T5 lamps turn on instantly, hot or cold.

Let’s not forget CF (compact fluorescent) bulbs, either. The technology has come a long way, but be aware that cheaper brands do not have a lot of choices and do not last as long as some of the better commercial brands. CFs may not be the right choice in some applications, especially where you want instant brightness. But CFs use only 25 percent as much energy as incandescents, and the labor savings with better long-lasting CF bulbs can be huge. Disposal is more costly, but the same as with fluorescent bulbs.

With these easy changes, the impact on your electric bill will be dramatic.