introduction
At present, building a conservation-oriented society has become an important national policy of China. The “Eleventh Five-Year Plan for Urban Green Lighting Project†issued by the Ministry of Construction requires annual energy saving targets of 5% for urban road lighting, and 5 years (2006~) In 2010, the cumulative power saving should reach 25%. Power saving has become an important task for urban road lighting management units. At the same time, it has been paid more and more attention by local governments, accelerating the construction of urban road lighting and electricity saving.
At present, urban road lighting and power saving work is mainly based on the application of new technologies. For example, the voltage regulating and power saving technology for high-pressure sodium lamps and the single-lamp power-adjusting ballast have been applied more, and at the same time, new light sources such as LED street lamps, Electromagnetic induction lamps and ceramic metal halide lamps are also used as energy-saving products to promote the application. The urban road lighting power-saving scheme presents a situation of 100-plus, and what kind of node scheme is really suitable for road lighting?
According to the "Eleventh Five-Year" Urban Green Lighting Project Planning Outline, energy-saving equipment and measures must be safe, reliable, scientific and reasonable, economical and easy to maintain, and ensure that urban lighting system functions meet various technical indicators and energy-saving effects; Scale and economic strength, strictly in accordance with standard design, construction according to plan; prevent the pursuit of energy saving at the expense of lighting effects. Therefore, urban road lighting power saving is not simply a power saving problem. At the same time, it is necessary to consider investment cost, operation and maintenance, equipment management, and road lighting technical indicators, and solve it when formulating a power saving plan. First of all, we must understand the current status of urban road lighting, including road lighting power density, road lighting (photo), lighting source.
1. Analysis of the basic status quo of urban road lighting
1.1, urban road lighting power density and illumination
Taking Guangzhou as an example, the lighting power and illuminance status of some roads were tested, and the illuminance measurement and power consumption analysis of 24 main roads were analyzed (see Table 1), among which:
The maximum power density (LPD) is 2.59, the minimum is 0.69, and the average is 1.18. There are 17 roads exceeding the 1.05 standard (the actual LPD value of 5 roads is less than 1.05, but the existing illumination is converted to 30lux). When the time is higher than 1.05, the value above this value is considered as non-energy-saving road), accounting for 70.8%;
The average illuminance is up to 99.62 lux, the minimum is 10.85 lux, and the average is 39.2 lux, of which 6 (30%) are 30 to 40 lux roads, and 8 (33.3%) are roads below the 30 lux illuminance standard.
The average illuminance per unit LPD value is 51.6, the minimum is 15.07, the average is 32.8, and the road below 68.6 (power density value is 1.05, average illuminance 30 lux) has 6 roads (25%);
Table 1 Road measurement parameter table
Comparison project | Power density | average illumination | Illuminance value per unit power density Lux/LPD |
Maximum | 2.59 | 99.62 | 51.6 |
Minimum value | 0.69 | 10.85 | 15.07 |
average value | 1.18 | 39.2 | 32.8 |
1.2, LPD exceeds the standard is a common problem in urban road lighting in China
In the study of urban lighting development direction and energy saving, the data of 22 road lighting conditions in 10 cities across the country showed that the average illuminance of the road was 66 lux, which was 30 lux higher than the design standard main road, which was 120% higher. The lighting is seriously exceeding the standard, and the LPD value generally exceeds the design standard, and some of them are non-cutting lamps, and the standard is over 2.4.
1.3. From the analysis of the data of relevant tests, the following conclusions can be drawn:
(1), LPD exceeds the standard is the main reason for the increase in power consumption and waste of road lighting;
(2) Even if they are all high-pressure sodium lamps, the illuminance values ​​of different roads converted into LPD are quite different. Take the above data as an example, the lowest is 15.07, the highest is 51.6. Such a big difference is the maintenance, the efficiency of lamps and light sources. It can not be ignored, and has become an important factor affecting the value of LPD.
(3) The illuminance of each road is quite different. One-third of the roads have lower average illumination than national standards, and one-quarter roads (average illumination 30~40lux) may be lower than national standards after power saving; At the same time, the impact on various functional indicators of lighting should be fully considered.
2. Lighting power density standard is the standard for urban road lighting power saving transformation
From the previous survey of road lighting power consumption, there is a general situation that the brightness is too high and the LPD exceeds the standard. The essence of road lighting power saving is to reduce the LPD value, but the LPD is not as low as possible, and must be guaranteed. The lighting indicators after power saving meet the functional requirements, so the power saving transformation should be carried out according to certain standards to meet the power saving rate and lighting quality requirements.
The Urban Road Lighting Design Standard (CJJ45-2006), which was implemented on July 1, 2007, uses the LPD standard as an evaluation index for road lighting power saving and is implemented as a mandatory standard. The LPD value ensures that the lighting requirements of the road lighting are met while meeting the energy saving requirements. The new road lighting is mandatory to meet the standard in order to achieve the power saving effect. The standard is also applicable to the energy-saving transformation of old road lighting. After the power-saving transformation of the excessive LPD road, the LPD value and illuminance should also meet the various indicators in Table 2.