A light tower is a piece of mobile equipment which has one or more high-intensity electric lamps and a mast. Almost always, the lights are attached to the mast, which is attached to a trailer, with a generator set to power the lamps. Normally the lamps are metal halide bulbs and the generator is powered by a diesel engine. However, battery-powered, solar-powered and hydrogen-powered sets are available; light towers with electrodeless lamps lighting are also sold. Modular kits permit separation of the generator set, trailer, lights and mast from each other. Another variation is an inflatable mast.^[1] Particularly when an inflatable mast is used, the lights may be placed close to the ground, with a reflector attached to the mast.^[2] When soft lighting is wanted, an inflatable "balloon" diffuser may be used. An inflatable mast may serve as a diffuser.

Light towers are used when illumination is required but not otherwise available, both outdoor and indoor, usually temporarily. Example activities are construction, mining, motion picture production, demolition,^[3] emergency services, sport or agricultural sectors.

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  construction of military base
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  light tower (far left) at open-pit coal mine
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  repairs to building
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  construction of highway tunnel
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  light towers (upper left) used in construction of bridge
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  construction of military base
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  military training for construction
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  construction of wind turbine
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  light tower placed at street intersection by Baltimore Police Department

• High-mast lighting
• Moonlight tower

• Equipment World article on light towers