What is the difference between LED sports lighting and metal halide lamp system in terms of energy saving?

　　This article compares LED sports lighting and metal halide lamp systems in terms of energy saving, and draws important conclusions through the comparison of two engineering examples.

　　1. Comparison of the whole system

　　The whole system refers  a complete lighting system from luminaire layout, lighting calculation,  lighting power distribution and control.

　　Figure 1 Sports Lighting Renovation of Pudong Natarium

　　Figure 1 shows the sports lighting renovation of Pudong Swimming Pool. The original system was a metal halide lamp, which was transformed in an LED sports lighting system after the whole system renovation. The main technical parameters before and after the renovation are shown in Table 1. Before the transformation, 62 sets of metal halide lamps were used, the installed power was 43.8kW, the average horizontal illuminance was 451lx, and the illuminance--power ratio=451/43800=0.0103lx/W, that is, only 0.0103lx of light can be obtained with 1W of electricity. After the transformation, only 44 sets of LED lights were used, the installed power was 11.88kW, which was reduced by nearly 73%, and the illuminance was increased by 104lx, and the illuminance--power ratio reached 0.0467lx/W, which was 4.5 times that of the metal halide lamp.

　　2. Comparison of lamp replacement

　　The original lamp position remains unchanged, and the original lighting system is used as much as possible, but the lighting calculation needs  be re-calculated, and the lighting distribution and pipelines are only partially adjusted. Obviously, this method is not completely reformed, but it is more economical.

　　Figure 2 Lighting renovation of a fencing hall

　　Figure 2 shows the lighting renovation of a fencing hall in Beijing. The original system was a metal halide lamp, but now it is changed  LED. The comparison before and after the renovation is shown in Table 2.

　　Table 2 Comparison of lamp replacement only

　　It can be seen from the table that the tal lighting power after the transformation is only 14.4kW, less than half of the original system; the average illuminance has increased by 100lx  850lx; the illuminance--power ratio is as high as 0.0590, which is 2.52 times that of the original system.

　　3. Conclusion

　　LED sports lighting is significantly better than metal halide lamps in terms of energy saving, and the overall design of the lighting system has a better energy saving effect.