Energy-Saving Ideas with Metal Halide Lighting

• Metal halide lights are long-lived and efficient. Jupiterimages/Photos.com/Getty Images

  High-intensity discharge (HID) lights are ideal outside security lights. One common HID light is the metal halide light bulb, often used to light large indoor areas, such as gyms and underground parking garages. The oblong-shaped bulb produces a brilliant white light with high efficiency, similar to hallogen lights.

Using a New Ballast

• Sometimes energy that could be saved is lost due to improper installation. HID bulbs do not work in regular lighting fixtures. Metal halide light bulbs require a ballast, a device that limits the amount of current received in an electric circuit. The on/off feature saves energy because the light automatically turns off when enough natural light returns to illuminate a room or porch.

Motion Sensors

• Because the HID bulb needs to calibrate to its balast, the bulb may take several minutes to reach full brightness. Due to the long warm-up time, metal halide bulbs are not meant for motion-sensor lighting sources in the on/off mode; the calibration time uses up energy and does not provide instant illumination. Make sure that your metal halide bulb is not in the on/off setting if you are using the light for an outdoor or indoor motion sensor. However, a metal halide light works well in conjunction with motion sensors that offer either on/off or hi-lo levels. Low-level light provides 50 percent power and 30 percent full-light output when no motion is detected. When the motion sensor detects motion, it triggers the lighting to go to the highest light level.

Use Existing Ballasts

• To save energy, you can use a reduced-wattage bulb for a metal halide lamp. A few screw-in metal halide lamps save energy if installed on existing ballasts. The lamp must be a specific retrofit lamp, custom made to refit a ballast.

Pulse-Start Lamps

• If you choose to replace the ballast, use a pulse-start metal halide lamp and ballast system. When you turn a regular metal halide lamp on, tungsten sputters from the electrodes and, over time, reduces the lamp's performance and efficiency. Pulse-start metal halide lamps, however, do not have the starting probe electrode but use a high-voltage ignitor that starts the lamp with a series of high-voltage pulses. Reducing heat loss and tungsten sputtering, pulse-start lamps save a lot of energy and the warm-up time is also reduced. Generally pulse-start lamps use 20 to 30 percent less electricity at the same illumination level than regular metal halide lamps.