1. Analysis of industrial development status As the country's per capita income is getting higher and higher, the number of cars in my country is growing faster and faster, and the area of underground parking lots is also getting bigger and bigger. Since underground parking lots have no light-transmitting windows, lighting fixtures generally need to work 24 hours a day, and the annual electricity bill is quite huge. In particular, the use of traditional fluorescent tubes has high power, short life, and a large amount of replacement and maintenance work, which is a difficult point in property management. Therefore, it will be a general trend to replace underground garages with more energy-efficient and ultra-long-life LED lamps in the future. However, the LED itself is a semiconductor device and can only be driven by direct current. Therefore, current LED lamps need to be equipped with a driver that converts alternating current into direct current. This leads to an increase in the overall cost of the LED lamp, but a decrease in efficiency. Solar energy and LED are both important elements of the national sustainable development strategy, and local governments have promoted the "Golden Sun" demonstration project. Since most of this type of projects use the inverter method, the inverter has losses, and the inverter equipment needs investment, which will undoubtedly cause the efficiency of the inverter system to drop and the cost to increase. At present, the economic benefits of solar inverter grid-connected power generation are not high and do not have practical value. If it is promoted on a large scale, it will inevitably cause unnecessary waste. Since the inverter grid-connected technology does not have the conditions for marketization, it should be considered to directly use low-voltage DC photovoltaic power. The application of solar energy and LED to the underground parking lot is obviously the best combination. In addition to responding to the requirements of national policies, it can also maximize the practical value of solar energy and LEDs, achieve high efficiency and low cost, and truly achieve the purpose of energy saving and emission reduction. The solar-powered underground parking lot LED lighting system meets the requirements of national policies, has real economic benefits, and has broad market prospects. At present, related companies in China have started to develop similar systems and built some demonstration projects, which have obtained good evaluations. The LED lighting system of the solar underground parking lot is still in its infancy, and there is still a lot of room for development in the future. 2. Project introduction This system is mainly developed for the serious energy consumption of the urban underground parking lot lighting system and the difficulty of maintenance and management. Through photovoltaic power generation, there is no need to go through inverter conversion, and directly drive LED lamps to provide clean and pollution-free lighting for underground garages. Very suitable for: large-scale real estate community, government agencies, hotels, shopping malls, hospitals and other underground garages, stairs, aisles and other lighting. "Non-inverter solar underground parking lot LED lighting system" uses solar cells to convert sunlight into electrical energy. On the one hand, the controller directly supplies electricity to the lighting load, and on the other hand stores the remaining electrical energy in the battery for night When the power generated by lighting or solar cells is insufficient, it is used as a backup. The power supply of the system can be connected to the city power grid, and it can automatically switch to the city power supply when it encounters continuous rainy weather to ensure the normal operation of the lighting system. The innovation of the project is to use low-voltage DC power supply from solar cells to provide lighting for underground garages, avoiding the disadvantages of reduced efficiency and increased equipment investment caused by inverters. So that the application of solar energy and LED can bring real economic benefits. Expected goal: The system design goal is to reach more than 60 kilowatts, which can meet the underground parking lot of more than 100,000 square meters. When the battery is powered, the lighting system can be guaranteed to work continuously for more than 24 hours. The controller has an intelligent control mode, which will automatically switch to a power saving mode when there are few cars late at night, reducing the brightness of the light source and reducing energy consumption. The design life of the solar power system is more than 10 years, and the design life of the LED lamps is more than 5 years. The controller has a remote monitoring function and can be connected to the monitoring room of the building to realize real-time monitoring of the system's operating status. Expected economic indicators: Taking a parking lot as an example, the area of an underground garage that needs to be illuminated is about 10,000 square meters. Calculate the annual electricity consumption based on the traditional fluorescent tube lamp lighting reaching 45lx illuminance requirements to meet the average power of 3W/㎡, and the flat lighting rate is 80%: 10000㎡*3W/㎡*24 (hours)*365 days*80% /1000=approximately 210,000 kilowatt hours. If you switch to solar LED lighting, the overall energy saving rate of the system is as high as 85%. Compared with traditional lighting, it can save about 180,000 kilowatt-hours of electricity each year, which can save the country 70 tons of coal and reduce 31 tons of carbon dioxide emissions. The incremental cost investment can generally be recovered within 3 years, and the economic benefits are very significant.