LED street light replaces traditional lighting scheme evaluation and analysis

LED Street Light Demonstration Program - Oakland, California, USA

For example, the US Energy Agency's demonstration of LED streetlights in Oakland, California, takes a two-stage evaluation process. The first-stage research team selects the parking lot in Auckland City to make measurements before and after the installation. The purpose is to evaluate whether the LED lighting may have a negative impact on safety when it is actually deployed on a general street; after confirming that the device has no special negative impact on the local people, the second stage of the operation is to install and evaluate the actual road and pass the local Residents survey estimates of satisfaction, acceptance, and economic costs.

This plan is an evaluation of the lighting effect of LEDs in streetlight applications. It replaces the original high-pressure sodium lamps with LED lights to conduct research on the roads in Auckland. The assessment methodology was evaluated using four projects, including source output efficiency, energy and power usage, user satisfaction surveys, and economic cost estimates. This assessment project expects the California region to more quickly introduce emerging energy technologies and applications that have not yet been adopted, through energy savings, reduced demand, market potential, market entry barriers, increasing costs, and expected technology lifecycles.

The purpose of this evaluation program is to evaluate the power, light source efficiency, and economic performance of high pressure sodium lamps compared to LED lamps. Potential economic needs and energy savings are assessed using average wattage and estimated annual kilowatts; light source performance is considered in terms of illuminance, uniformity, correlated color temperature, and the satisfaction of the relevant group. Finally, economic performance is replaced by equipment or replacement. The payback period (simple-payback), lamp life, maintenance costs, and power costs are evaluated.

Compared with traditional lighting sources, LEDs provide better lighting capabilities in terms of light source dispersion and energy saving, and at the same time change the general industry's perception of the use of high-quality light sources, and also apply to streets and general roads. The current street uses high-pressure sodium lamps for lighting, while others use metal halides, low-pressure sodium lamps or other types for lighting. The use of high pressure sodium lamps is due to their long service life and higher efficiency compared to other conventional lamps, but less selectivity in color supply. LEDs have a longer service life than high pressure sodium lamps, lower maintenance Cost, multiple types of color supply, low energy consumption and cost savings. However, the initial cost of using LEDs is still higher than that of commonly used lighting sources.

According to the US Energy Administration's report, the current LED technology changes are quite fast. Overall, LED's annual luminous efficiency is about 35%, and the cost can be reduced by 20%.

Plan implementation location and assessment method

This LED streetlight demonstration program replaces the original 121-watt high-pressure sodium lamp (HPS) with 15 盏 78 watt LED lights on the two roads of Sextus and Tunis in Auckland. For comparison and comparison, the east side of Sextus Road is installed. The new high-pressure sodium lamp is equipped with LED street lights on the west side; all the LED street lights are installed on the Tunis road, and new high-pressure sodium lamps are installed on the adjacent Cairo road. All fixtures are mounted at 28.5 feet above the road and have a pole spacing of 110, 120 or 160 feet.

The study found that the average power used per LED street light is 77.7 watts, which saves about 35% of the electricity compared to the average power of HPS of HPS, which is estimated to be 4,100 hours a year. Under 178 kWh.

Before each stage of the LED evaluation test, there will be a pre-test operation, all tests are carried out after dusk, and the distance between the lighting fixture and its two lighting fixtures is 110 feet, and the second and third of them are The distance between the two is 165 feet, and the distance between the three lights and the four street lights is 120 feet. As far as is reasonable, the illumination uniformity of the luminaire should be the same, but when the actual setting and evaluation, the street lamp can not be set within a yard within the distance when setting at the intersection. The distance from north to south is 12 feet. The width is adjusted to 10 feet.

The measurement method of this evaluation project is slightly different from the way of the international road lighting specification (IESNA) street lamp setting measurement. The international road lighting specification recommends that the measurement position should be within the range of one square of each distance directly below the light source. The measurement range of this study is in the light source. The bottom is directly measured and the center point position between the two light sources is measured, the maximum and minimum values ​​of the illuminance are predicted within the test range, and the degree of difference between the uniformity of the high pressure sodium lamp and the LED lamp is recorded. The sensor is recommended to be installed 6 feet from the ground. The research team considered past measurement experience and recommendations and set the measurement position at 18 feet, which is the lowest height when the tripod is combined with the sensor.

The measurement process also includes the measurement of the temperature, and the high-pressure sodium lamp and the LED lamp are respectively measured every 20 minutes by using an electronic thermometer; in addition, in the night of measuring the LED lamp, the relative humidity is obtained by using the HOBO instrument U12 data recorder every 30 seconds. Other temperature measurements. There are related measurement information about LED lights and high-pressure sodium lamps, including photo shooting at various angles, power, illumination, color temperature and ambient temperature.

For the measurement of power consumption, a single high-pressure sodium lamp and LED lamp are measured by the DENTElite data logger. Since the test project has been in a period of time, the measuring instrument must be placed at a height position that is difficult to be directly contacted by the ground, and the research project personnel rely on it. The Auckland Street Light Maintenance Team assisted in the installation and removal of measuring equipment, and there were no special differences in power consumption during the measurement period.