Halogen bulbs cost more up front than regular incandescent bulbs. Despite this, halogen bulbs cost less overall to use. The first reason for this is that halogen bulbs operate with more energy efficiency. Halogen and incandescent bulbs have the same basic parts and produce light from the same source: a tungsten filament that glows when heated to a high temperature. As the filament burns, bits of the tungsten break off. As more tungsten burns off, the light bulb gets dimmer and dimmer until it ultimately burns out. The key difference with the halogen bulb is that this tungsten burn-off process happens much more slowly. In a halogen bulb, the tungsten filament is encased in halogen gases that help push the fallen bits of tungsten back onto the filament. The longer the tungsten lasts on the filament, the longer the light bulb will last.
The subtle differences in halogen over incandescent mean you can buy a halogen bulb with a lower wattage than that of an incandescent bulb and still get the same kind of light. Lower wattage translates to less energy use, which means a lower electricity bill. And because halogen bulbs last longer than incandescent bulbs, they need to be replaced less often. That can save consumers time and save money in labor costs for an office building, for example. The average incandescent bulb has a life expectancy of 1,000 hours, but the average halogen bulb is expected to last three times as long [source: Energy Star]. Light bulb maker GE also points out that consumers should look at the lifetime energy and cost savings a bulb accrues when looking at its retail price. With halogen lights, the company says, you can avoid wasting wattage on invisible infrared energy. More goes into useful light [source: GE].
Of course, buying halogens simply is one step toward energy savings from light bulbs. It's estimated that a compact fluorescent bulb that is Energy Star qualified can save up to $40 in electricity costs over its lifetime and an Energy Star LED bulb uses at least 75 percent less energy than a typical incandescent bulb [source: EPA].
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