Outstanding energy saving! This LED street light technology has been recommended multiple times by government departments

The 2022 National Energy Saving Publicity Week was from June 13 to 19, with the theme "Green low-carbon, energy saving first". The National Low-Carbon Day is on June 15, with the theme "Implementing 'Dual Carbon' actions, building a beautiful home together".

To widely carry out energy-saving and carbon-reduction publicity and education, and vigorously advocate green, low-carbon production and lifestyle patterns, China Lighting Network, Agricultural Lighting Network, and Ming Classroom jointly solicit energy-saving and low-carbon technologies and project cases from lighting enterprises and user units (details: 2022 National Energy Conservation Week Lighting Energy-Saving and Low-Carbon Case Solicitation ). This issue presents a submitted case: the Nanzhuang Highway Lighting Project in Fengxian District, Shanghai.

Lighting Engineering Project of Nanzhuang Highway, Fengxian District, Shanghai

Demonstration Project Team:

Shanghai Yiyong Optoelectronics Technology Co., Ltd. — Product Provider

Lighting design overview and lighting design proposal

"Yiyao" brand LED high-efficiency energy-saving street lights mainly solve the two major technical challenges affecting the promotion and application of replacing traditional lighting:

The vast majority of LED street light products (refractive lens optics) produced by manufacturers today achieve an average energy saving of approximately 30% compared to traditional high-pressure sodium lamps at the same illuminance; the energy-saving effect is merely passable . By applying new technologies (reflective light-guide module optics), energy savings compared to high-pressure sodium lamps at the same illuminance can be increased to over 60%!

Key Technologies:

1. Road cross-section direction (perpendicular to traffic flow) adopts asymmetric secondary optical distribution design via light-guiding modules (replacing lenses for secondary distribution, except for the primary 'light source' distribution). Light-guiding modules effectively control 'upward viewing light' and 'backlight', resulting in more uniform and effective light distribution! (Light passing through lenses suffers luminous efficacy loss due to refraction and is uncontrollable)

2. LED junction temperature cannot be effectively dissipated, leading to lumen depreciation, which severely impacts service life!

Yiyao brand LED street lights adopt heat pipe cooling technology. Through a unique heat conduction transfer cooling system, they ensure the light source operates in a normal temperature-controlled environment. After repeated simulation experiments, the system's junction temperature rate matches the heat extraction rate and heat dissipation rate. The die-cast aluminum top cover is designed as part of the large thermal mass, giving the luminaire an exceptionally large thermal mass. Actual measurements show the temperature difference between the heat source center point and the farthest end is only 1 degree.

Design standards followed

1. "Code for Design of Urban Road Lighting" (CJJ45-2015)

2. Safety requirements for luminaires for road and street lighting (GB7000.5)

3. Technical Specification for Automatic Control System of Urban Lighting (CJJ/T227-2014)

Main semiconductor lighting technical parameters and details

Nanzhuang Road (secondary arterial) adopts for the first time a light-guiding module system for secondary optical distribution , with a system power of 90W and color temperature: 4000K. If lenses are used for secondary optical distribution, the system power exceeds 120W. After applying innovative technology, a comparison of lighting compliance between two different optical distribution technologies shows that reflective solutions save 40.6% in energy. By implementing single-lamp control via power line carrier communication, further secondary energy savings can be achieved.

Energy saving effects and environmental impact

A total of 10 kilometers of Nanzhuang Highway in Fengxian District, Shanghai, with a pole height of 8 meters, road width of 10 meters, single-side pole installation, and pole spacing of 28 meters. This section is a 'road without lights' livelihood project funded by the Fengxian District Finance Department, constructed and operated on behalf by the District Highway Office, with electricity fees paid directly by the Jianghai Town Government as the energy user.

Single-lamp energy saving (maintaining the same illuminance as the original design high-pressure sodium lamp per owner's requirements): 298.48 * 60.7% = 180.87 W; with daily lighting time of 11.5 hours, a total length of 10 km saves electricity costing 357 * 11.5 * 0.1809 * 0.7 = 520.09 CNY. Annual electricity cost reduction is 520.09 * 365 = 189,800 CNY; users are very satisfied! If calculated based on the national standard upper limit for secondary roads (energy saving 80.9%), annual electricity savings would reach 257,900 CNY.

Environmental Indicators: Annual CO2 reduction (calculated at 0.75kg CO2/kWh) 20.34 tons of CO2; annual standard coal savings 9.85 tons.

Effect

Currently, the vast majority of street lights on the market use lenses for light distribution. Approximately 11% of luminous flux is lost due to refraction. If the lens is not precisely dimensioned according to actual road conditions, it cannot uniformly and effectively direct the refracted light onto the road surface, resulting in uncontrolled light (upward glare and backlight), with about 26% of the light projected into the sky and beyond the road. Road lighting is a 'non-imaging' functional lighting application; abandoning lenses has its rationale. Company adopts a new light-guiding module for secondary optical distribution, achieving uniform and efficient luminous intensity distribution. The utilization rate is improved by 30% compared to using lenses, with overall luminous efficacy reaching over 85%.

Owner feedback

1. Awards Received:

Shanghai Energy Saving Product Award, National Electronic Energy Saving Key Recommended Product Technology Award, Shanghai LED Technology Innovation Award, Top 100 International Semiconductor Lighting Demonstration Projects

2. User Verification:

On September 21, 2015, the Fengxian District Highway Management Office of Shanghai adopted 77 "Yiyao" brand 137W LED street lights for installation on Nanzhuang Road. Completed content: 1) The luminaire uses a daylight-type fixture with a high-pressure aluminum-plastic one-piece molded housing; the light bulb is adjustable with a symmetrical wing-type luminous intensity distribution curve (LDC). 2) The luminaire reflector is made of high-purity aluminum, and the lens is high-transparency heat-resistant curved tempered glass. 3) The luminaire includes a built-in power factor compensator; after compensation, COS Ø > 0.9. 4) The LED driver is installed inside the pole base and adopts intelligent driving. 5) A five-year service life guarantee is provided, and illumination measurement indicators comply with national standards (GB / GB/T). Due to the excellent energy-saving performance of the Yiyao brand LED street lights, the user expressed recognition and satisfaction.

3. Expert evaluation opinion of the Housing and Urban-Rural Development Commission:

1) Adopting "heat pipe technology" improves the luminaire's heat dissipation efficiency, reduces LED lumen depreciation, and extends the LED light source lifespan. 2) Applying optical reflection principles, we independently designed a secondary optical distribution reflector for LED street lights, improving lighting utilization. 3) Developed an integrated LED "smart power supply" combining power supply, control, and communication modules, enhancing energy saving and management levels. The LED luminaires and smart lighting system developed in this project achieve an energy saving rate of 61%.

Source: International Solid-State Lighting Alliance (ISA)