LED solar street lights become the choice for energy-saving renovation of road lighting

The average illuminance of the road surface is one of the evaluation indicators for the lighting of urban motor vehicle traffic roads and pedestrian roads, and it is also an important reference indicator for the configuration of street lamps. LED solar street light is a high-efficiency solid-state light source based on semiconductor PN junction that can emit light with weak electrical energy. Under a certain forward bias voltage and injection current, holes are injected into the P region and electrons are injected into the N region. After diffusing into the active region, it is radiatively recombined to emit photons, which directly convert electrical energy into light energy. It is a solid-state cold light source, which has the characteristics of environmental protection, no pollution, low power consumption, high light efficiency and long life. Therefore, led solar street lights will become the choice for energy-saving renovation of road lighting. In order to configure or replace urban roads with led solar street lights, the calculation of relevant lighting indicators is the first step in technology. It is a solid-state cold light source, which has the characteristics of environmental protection, no pollution, low power consumption, high light efficiency and long life. Therefore, led solar street lights will become the choice for energy-saving renovation of road lighting. It is a simple and effective method to use the coefficient method to calculate.

Starting from the conclusion of traditional lighting theory, the calculation formula of 'utilization coefficient' is completely copied. All we have to do is to input some experimental or theoretical data of led solar street lights into the formula, get the results, and compare them with the requirements of road lighting design standards. It goes without saying that these calculations are also necessary for the design, development, improvement, improvement and marketing of LED solar street lights.

The utilization factor (U) is the ratio of the luminous flux directly irradiated on the road to the luminous flux emitted by all light sources, which is related to the height, elevation angle, layout and width of the road.

Luminous flux (Φ) is the sum of the energy emitted by the light source and the energy received by the human eye. Represents the radiant energy per unit time, expressed in lumens lm. Other representations: (cd is the unit of luminous intensity: Candela.Sr is the unit of the cube corner sphere.

Illuminance (e) is the proportionality factor between luminous flux and illuminated area in lux (lx). 1lx refers to the average energy of 1lm luminous flux distributed in an area of ​​1 square meter, ie lm/m2.

The average illuminance of the road surface (eav) is the average value of the point illuminance measured or calculated by the LED solar street light manufacturer at the preset points on the road surface according to relevant regulations.

The maintenance factor (k) is the ratio of the average illuminance or average brightness on the same surface to the average illuminance or average brightness on the same surface when the lighting device is newly installed under the same conditions after being used for a certain period of time.

The installation height (H) of the luminaire is the vertical distance from the light center of the luminaire to the road surface.

Luminaire installation spacing is the distance between two adjacent luminaires measured along the centerline of the road.

The hanging length (xl) is the horizontal distance from the light center of the lamp to the adjacent edge stone, i.e. the horizontal distance the lamp extends or retracts.

The effective width of the road surface (Weff) is the theoretical width of the road surface used in the road lighting design, which is related to the actual width of the road, the overhang length of the lamps and the arrangement of the lamps.