LED Public Lighting Project in Fudan University Written by Feng Yuting and Lin Li, from Fudan University, China LED means light emitting diode, which is a green light source. Though the present market for finished white LED products is geared mainly towards enthusiasts and early-adopters, our students want to lead the step to publicize this environmental-friendly new tool on campus. This project was started four years ago, in 2006, for the public lighting on our campus. It is special and creative since all the LED lamps are made by our students from Dept.of Light Sources & Illuminating Engineering under the guidance of Prof. Liu Muqing. Students hope the LED public lighting project will not only be beneficial to energy conservation but also inspire our stronger awareness of sustainability.
Why is LED? Environmental friendly, of course! Without any mercury, LED
non-pollutant. It reduces a large number of harmful gases such as sulfur dioxide and nitrogen compounds, carbon dioxide and other greenhouse gases. (LED bulb, photo by Feng Yuting) It’s compact, thin and light.Its narrow-spectrum provides bright and pure color. The good visual effects will set us in a comfortable lighting area. The semiconductor component brings long lifecycle to 50,000 ~ 80,000 hours in practice. The key strength of LED lighting is to reduce power consumption, which means 80% of the electrical energy is converted to light energy with lowered heat emission.
How is the LED public lighting project? A. Basic Information At present, there are 16 white LED lamps which are placed in northern dormitory area. Despite the starting year in 2006, after a series of R&D, test run and installation, these lamps have been lighting up for 18 months. Road illumination of each white LED lamp is 35lx. The expected operational life of current white LED lamps made by our students is at least 26,280 hours. Compared with previously used high-pressure sodium lamp, these white LED lamps save more than 50% energy. B. Output efficiency The initial investment of these lamps are relatively high, and according to calculation, each is around RMB 3,000. However, Students’ LED design is over 50% efficiency, that means every lamp saves RMB 525.6 (0.15KW×12 hours ×365 days×RMB 0.8) per year, and a tatal of 16 lamps save RMB 12614.4 (RMB 525.6×16 lamps×1.5 years) in 18 month. No more than 2 to 3 years, we can recover costs. Realistically the cost savings would be higher as most high-pressure sodium bulbs (RMB 400 each) blow out within 4,000 hours and thus require replacements, whereas our LED lamps can be used easily for at least 6 years without burning out.
(White LED lamps in Fudan University, photo by Feng Yuting)
C. Technical Perfection Stability: Look, everything is running well in these 18 months! Waterproofing: This problem is significant to LED since its poor waterproof ability is the Achilles heel of outdoor use. Futhermore, the weather in Shanghai is humid and rainy in summer. Our students use the technology of mold resistance and sealing rings to solve this problem. Recycling: LED lamp can be recycled since its tube material is PC, a green material. What’s next? We are looking forward to replacing most of the public lighting system with sustainable LED lamps on campus, but currently, there would be a really long process. Anyway, we believe it is a good start for us to implement this project.