Lighting Systems

The three most common lamp types for high-intensity lighting are high pressure sodium (HPS) lamps, metal halide (MH) lamps, and LEDs.

HPS Lamp (high pressure sodium)
HPS lamps are the most common lamp type used in greenhouses today due to their high energy efficiency, moderately long bulb life and relatively small fixture size, and cover biger area and work well in biger hights. 

MH lamps. (metal halide)
Metal halide lamps are less common, but are especially used by garden center retailers who use their retail space for production early in the season.

High-intensity LEDs 
These are slowly taking more market share in horticultural lighting. There continues to be large improvement in the technology and light intensity of the lamps.They require more installation space to the site.