How Solar LED Street Lamp Saves Energy?

Solar led street lamps provide illumination for roads, highways, intersections, parking lots, and rural areas, which increase visibility, ensure the safety for drivers and reduce crime rates. Some people may think that the solar led street lamp applications are limited by weather (without rich sunlight). In recent years, new technologies on battery and solar panel have emerged to make streetlights more cost-effective and the integration with internet of things technology has improved the level of public management in the city. 

Save energy or electricity bills is the purpose of all countries over the world. 50% of the population in Africa still lives without electricity. The off-grid solar led street lamp seems to be the only solution for their illumination and development. Today, most of the street lights installed everywhere the planet are traditional. They generate expensive electricity bills and consuming fossil fuels. Replace the traditional solar led street lamp with solar led street lamps can greatly reduce the electricity bills. Because the solar led street lamp use the sun light as energy source, and the sun light is green and environmentally friendly. So, how can solar led street lamp save the electricity bills and how to transfer sunlight into electricity?

1. Economical choice

Each solar led street lamp is a relatively independent system. During the construction of the lighting project, there is no need to bury cables or excavate the road, thus saving a lot of manpower and material resources. If all a 20-kilometer highway is replaced with solar led street lamps, about 350,000 kilowatt-hours of electricity can be saved a year. Based on the average electricity bill of 0.6 RMB per kilowatt-hour, at least more than 200,000 RMB can be saved each year. Saving 350,000 kilowatt-hours of electricity is equivalent to saving about 128 tons of coal in disguised form. Simultaneously, it can reduce 56 tons of carbon dioxide, 33 tons of coal ash, 2 tons of sulfur dioxide, and about 15 tons of other wind dust and nitrogen oxides. This is the green and environmental protection of solar led street lamps.

2. Energy-saving principles of solar led street lamps

How do solar panels store electricity?

Sunlight shines on the semiconductor p-n junction to form new hole-electron pairs. Under the action of the p-n junction electric field, holes flow from the p-zone to the n-zone, and electrons flow from the n-zone to the p-zone, and a current is formed after the circuit is turned on. This is the working principle of photovoltaic effect solar cells. Solar panels only need to be exposed to sunlight to restore electricity. In order to minimize light reflection and increase the photoelectric conversion rate of the solar panel, it is generally necessary to cover a layer of film to avoid light reflection. The tilt angle of the solar panel will also have a great impact on the photoelectric conversion efficiency, so the tilt angle is generally calculated based on the local latitude.

How is solar light converted into electricity?

Solar led street lamps are mainly composed of photovoltaic components, light-emitting diodes, batteries and current limiters. The light-electricity direct conversion method uses the photoelectric effect to directly convert solar radiant energy into electrical energy. The basic device of the light-electricity conversion is the solar cell. A solar cell is a device that directly converts sunlight energy into electrical energy due to the photovoltaic effect. It is a semiconductor photodiode. When the sun shines on the photodiode, the photodiode will turn the sunlight energy into electrical energy to produce current. When many batteries are connected in series or in parallel, a square array of solar cells with relatively large output power can be formed.