Brief introduction to the popularization and application of LED street lamp in USA

The United States National street lamp 52 million, of which the road lights are the other half of the street lights and the city public square lights, is the world's largest urban lighting system, more than China (about 35 million or so). The United States Department of energy began in 2009, planning to replace the existing LED street lamp with the plan, its start-up time than our "Ten City" to be late. Is a part of the world LED street lamp, but the promotion of the plan and arrangement is more rigorous.

Due to the current LED road lighting performance is still difficult to meet the lighting requirements of the main road, economic returns are not ideal, so the United States LED road lighting is mainly concentrated in the sub roads and urban lighting on the road.

2010 began to choose from southeast northwest, inland and coastal areas in different geographic locations; technical and economic conditions are different, several towns of different sizes, different products and solutions to the pilot, more comprehensive test results obtained under various conditions. In the initial positive results, in other cities and towns on the basis of voluntary gradually expand the scope of. According to incomplete statistics, the current popularization and application of less than 5% of the total amount of street lamps. Now there is no one city to do the full use of LED street lights. Losangeles is the first to implement the world's largest LED road lighting program, plans to install 220 thousand LED street lamps, followed by the eastern Boston.

According to the above plan, in 2010, the establishment of a LED municipal road lighting alliance, to provide a platform for the exchange of experimental cities and professional departments. Its purpose is to break the limitations of the local, to reduce duplication of investment in the experiment, as far as possible to reduce investment risk, shorten the cycle of learning to use LED lighting. Summarize communication, provide uniform standards for project reviews, and tools.

Pilot city LED street lamp staged application test. The first stage is to explore the effectiveness of lighting conditions and improve the effectiveness of investment returns. The second phase of the expansion of the trial period, the pursuit of technology improvement, the establishment of standard, price level and application of the product to further improve, achieve in the application effect and economic benefits, environmental protection and energy saving, the social effect to attract social capital investment. The third stage is the introduction of social capital investment, so that LED lighting can be fully promoted. Some cities to promote the application phase is divided into five stages. Preliminary estimates, fully mature use to 2020.

In each city's LED street lamp to choose the test area, the use of geographic information system, according to the decision to promote the application of the weight of each stage of the test area. First, the project is to improve the lighting needs to take into account the return on the first place, after the return rate of LED lighting has been confirmed, the gradual improvement in stages, a higher return, the effect is obvious to give priority to.

The transformation project is set up and the results are summarized, which are based on direct lighting effect and economic benefit. Measure the success of the product from the expected return and the actual return. Other evaluation factors include resident habits, urban safety, lighting effects, etc.. Because of the different conditions of replacement, the cost difference. From the beginning of the summary of the pilot cities, the return on investment (excluding subsidies) cycle is between 2~7. Can reach an acceptable level. The alliance provides a tool for the transformation of urban street road reconstruction software, as long as the relevant information, you can automatically give the investment risk and return cycle, to avoid the human intervention and errors. Contribute to the lack of experience in the city, project evaluation, tender project tender design. Increase the transparency of municipal construction budget transparency, easy to monitor (LED road reconstruction of the economic analysis of the software input and output interface).

The core of the economic return of LED road reconstruction is the actual lighting efficiency and the improvement of maintenance cost. The accounting model and the light distribution design of lamps and lanterns, and the design of street lamp settings and contrast samples have a great relationship. In order to compare the original high pressure sodium lamp or the different distribution of LED street lamp and the setting, this paper puts forward a measuring method of FTE lighting efficiency. Full advantage of this approach is that will guide the staff to the main street design power to two improvement of optical design, the system can play a potential LED street, rather than locking in the lamp lumens per watt bounce point. Schematic diagram of ETF calculation method. Pilot city lighting energy saving effect from 20% to 60%, apparently due to the light distribution of light.

For economic and practical, the United States road and lighting are more emphasis on the target visibility, bias in the lower average illuminance. Therefore, the distance from the street design is generally higher than our country. The uniformity of the control requirements is not high, rarely involving the road surface brightness requirements. But for the sake of the pursuit of the target visibility and avoid nuisance, street lighting control requirements for the setting of more stringent. Relatively speaking, the cost of electricity consumption in the United States road lighting is relatively low, the lamp light distribution performance requirements are relatively high.

Most of the electricity from the road lighting is directly connected to the power grid, and the control of street lamp is generally based on adaptive control. Since the new LED street lamp is likely to receive dimming control. In April 2013, a new framework for adaptive and remote control of road lighting was established for the future of new LED products and system settings.

Street lamp road lighting color temperature problem, due to different applications, is still in dispute. Generally in the downtown area and public safety,