Research on Popularization and Application of LED Light Source in Energy Saving Reconstruction of Guangxi Municipal Street Lamps

Research on the Promotion and Application of Light Industry Technology bookmark0 Resources and Environment LED Light Sources in Energy Saving Reconstruction of Guangxi Municipal Street Lamps Lu Xien (Energy Conservation Supervision Center of Guangxi Zhuang Autonomous Region, Nanning 530023, China) The development of urban construction in Guangxi, the demand and quantity of road lighting and landscape lighting are increasing The energy consumption of municipal road lamps is increasing. At present, the management level and technical level of municipal road lamps are uneven. The high-pressure sodium lamps with high energy consumption are still used in large quantities, which has a large energy-saving space. In the municipal street lamps, by promoting the use of mature, energy-saving and economical LED light sources, large economic and social benefits can be obtained.

Table 1 2009-2011 Guangxi municipal street lamp energy consumption table year 2010, 2011 municipal street lamp power consumption (100 million kWh) 4. 535.054.89 full accounting power consumption (100 million kWh) 856. 4993.241112.32 municipal street lamp The proportion of electricity consumption to the total electricity consumption is 0.530.510.441.2. The number of energy-saving light sources in LEDs is very small in Guangxi municipal street lamps. Table 2 Types of municipal street lamps and power distribution in Guangxi cities. Number of street lamps. Ordinary light source sodium lamp 2223055248192093. 1 The structure and energy consumption status of Guangxi municipal street lamps 1.1 The basic situation of Guangxi municipal street lamps Through the questionnaire survey of the municipal street lamp management departments of 14 prefecture-level cities in Guangxi, combined with the 2011 prepared by the China Municipal Engineering Association Urban Road Lighting Professional Committee According to the data in the Yearbook of the Urban Road Lighting Professional Committee, there are about 760,000 municipal street lamps in Guangxi, with a total power of about 116,000 kilowatts. The power consumption of Guangxi municipal street lamps for the three years from 2009 to 2011 was 453 million kWh, 505 million kWh and 489 million kWh. They accounted for 0.53%, 0.51%, and 0.44% of the total electricity consumption of the whole society. Table 1 shows the energy consumption of Guangxi municipal street lamps in the past three years. It can be seen from the table that although the total energy consumption in 2011 is slightly lower than that in 2010, However, considering the tight power supply situation in Guangxi in 2011, the cities in the district have imposed power cuts on municipal street lights. Therefore, with the continuous increase of Guangxi municipal roads, the energy consumption of Guangxi municipal street lamps is increasing year by year. The trend.

At present, the light source of Guangxi municipal street lamps mainly includes high-pressure sodium lamps and energy-saving lamps (fluorescent lamps), and has a small amount of mercury lamps, metal halide lamps, electrodeless lamps and LED lamps. The main distribution is shown in Table 2.

It can be seen from Table 2 that in the current application of street lamps in Guangxi municipal roads, the new energy-saving light source LED lamps account for a small proportion both in quantity and power. At present, more than 93% of the light sources of Guangxi municipal street lamps are traditional high-pressure sodium light source street lamps, and the proportion of energy-saving LED light source street lamps is currently only about 2%, and the number is extremely small. Such a structure has led to a higher energy consumption of Guangxi municipal street lamps.

The technical and economic comparison analysis of 2 LED light source in the application of municipal street lamps is currently applied. The energy-saving transformation of municipal street light source is mainly to replace the original high-pressure sodium lamp with LED light source lamp. Installation tests have been carried out on some trunk roads in some urban areas of Fangchenggang City and Qinzhou City, and the energy saving effect is excellent. Based on the technical parameters and actual empirical data, the LED light source is used instead of the original high-pressure sodium lamp source to compare and analyze the technical and economic aspects.

2.1 Technical comparison Analysis of bulk light-emitting devices can directly convert electricity into light. It has neither a burning filament nor an ionized gas, so it works at very low temperatures. As an emerging light source, LED has obvious advantages over high-pressure sodium lamps in municipal road lighting applications, mainly in the following aspects: energy saving. In the application of municipal roads, the power saving rate can be as high as 50%-60% when the same illuminance requirement is met.

The illumination angle is controllable. The LED has a unidirectional radiation characteristic, and most of the light energy emitted by the LED can directly reach the object to be illuminated without being reflected, so that the light energy can be maximized, and the efficiency of the lamp is greatly improved.

long life. At present, a good LED brand, its life (ie, mean trouble-free working time) can reach 50,000h-100000h, which is more than 10 times that of sodium lamp. If it works for 11h every day, it can be used for more than 8-10 years.

LED light source can achieve no flicker, no ultraviolet light, very low heat radiation, no harm to the human eye, and can reduce the harm of light radiation compared with high pressure sodium lamp. The use of LEDs for indoor lighting or for lighting where people need to work and study for a long time can be truly eye-protecting.

LEDs have a high color rendering index of up to 80%, which is very close to natural light. Compared with the high-light sodium lamp, which is close to yellow light, under its illumination, people can better distinguish objects of different colors and recognize moving objects faster; therefore, it is especially suitable for indoor lighting and outdoor road lighting.

The color of the light is adjustable. The change of current can change color, and the light-emitting diode can conveniently adjust the energy band structure and band gap of the material through chemical modification method to realize multi-color luminescence of red, yellow, green, blue and orange. For example, a red LED with a small current can change to orange, yellow, and finally green as the current increases. The color of the high-pressure sodium lamp is fixed.

The driving power of LEDs is mostly a constant current driving power supply, and its power consumption hardly changes with the power supply voltage. This is different from the high pressure sodium lamp source. Because the grid voltage is higher at night, the high-pressure sodium lamp is more energy-consuming at night (the high-pressure sodium lamp power can be higher than the constant-current drive, and its power does not change with the power supply voltage.

The power of LED lamps can be set arbitrarily. LED lights are made up of several 1 ~ 3W LEDs in random combination. Determine the power of the luminaire according to different requirements. Each unit LED chip is a 3-5mm square, so it can be prepared into various shapes of devices, and suitable for a variable environment, it can make the illumination just meet the standard requirements, avoiding the high-pressure sodium lamp due to less power specifications, power is not Match the resulting over-illumination.

Green and environmental pollution: no harmful metal mercury, after the LED is discarded, almost all of its waste can be recycled, which not only saves resources, but also protects the environment. The high-pressure sodium lamp will pollute the environment after it is discarded.

LED lamps have the following disadvantages compared with high-pressure sodium lamps. LED street lamps themselves are too heavy, which is not conducive to installation and wind protection.

At present, the country does not have a unified and clear regulation on the technical parameters of all aspects of LED lamps, resulting in the current quality of LED lamps on the market. The quality of LED lamps with poor quality is far from the requirements for life and light decay.

Whether it is a single-point or multi-point light source LED streetlights have the problem of heat dissipation, because the manufacturers have different measures, the effect is not the same.

LED street light range can fully meet the requirements of municipal roads, but the range is limited, LED street lights need to further strengthen the study of how to work at higher altitudes.

Based on the above comparisons, LED lamps have obvious technical advantages and are more suitable for use in municipal roads than high-pressure sodium lamps.

2.2 Economic comparison analysis LED lamps and conventional street lamps are economically compared. The advantage lies in saving energy and reducing operating costs. The disadvantage is that one-time investment is high. The following is a comprehensive analysis.

From the technical characteristics of the LED light source and the practical application effect of the pilot road, on the municipal road, the 100W LED lamp can completely replace the 250W high-pressure sodium lamp. The following two models are widely used as typical representatives for comparative analysis.

From the application test to provide measured data, the average power per kilowatt in municipal roads is 250W. The high-pressure sodium lamp consumes 325W per hour, and the average LED power per 100W consumes 110W per hour. The time is calculated as the comparison period unit. The daily light-on time is 10 hours.

The unit price of street lamp electricity is taken from the average value of 0.85 yuan per degree in recent years. The installation cost of high-pressure sodium lamp is about 1800 yuan. The cost recovery period of LED lamp = purchase and installation cost difference + annual electricity saving fee for 5 years. It can be seen from the perspective of saving energy. The LED lamp replaces the high-pressure sodium lamp and can recover the cost in 5 years. The life of the LED lamp is about 8-10 years, so it can be seen that in the municipal road reconstruction, the profit obtained by replacing the high-pressure sodium lamp source with the LED light source is rich. From an economic perspective, LED lights are suitable for use in municipal roads.

3 Guangxi municipal street lamp energy-saving renovation promotion using LED light source path selection LED light source is currently the leading direction of municipal street lamp energy-saving light source selection for a period of time to the present, with significant energy-saving effect (power saving rate is about 50%-60%), wide application range High stability, good safety performance, long life, green and environmental protection and other traditional light sources can not match the advantages. In order to optimize the lighting system of street lighting and reduce the energy consumption of street lighting, in the future, new street lights in Guangxi should be mainly based on LED street lights, supplemented by other forms of energy-saving street lamps. The promotion of LED street lamps should be considered separately from the stock street lamps and incremental street lamps. Step-by-step update replacement.

3.1 Incremental street lights mainly use LED light source street lamps. Now the total number of street lamps in Guangxi is increasing at a rate of about 5-15% per year. If the average growth rate is 10%, the total number of street lamps in Guangxi is 760,000 baht. The total number of street lights at the end of the five-year road will reach 1,112,700, and the number of new street lamps will reach 352,700. In addition to about 30% of the newly added street lamps, the remaining 70% of the incremental street lamps (about 246,900 baht) should be LED street lights in principle. By then, the total proportion of LED street lamps will reach about 22%. By then, the energy saving of Guangxi municipal street lamps will achieve obvious results.

3.2 Gradually implement LED streetlights for stock street lamps. The construction of street lamps with relatively abundant funds for the construction of high-pressure sodium lamps of more than 250W should be replaced by LED street lamps instead, and strive to reach the end of the 12th Five-Year Plan and 250W and above. The transformation of the stock high-pressure sodium lamp is about 20%, about 66,000 盏 (according to the statistical yearbook data, the high-pressure sodium lamp above 250W in Guangxi area accounts for about 43% of the total number of street lamps, about 329,800 baht), that is, through 250W and above. The transformation of the stock of high-pressure sodium lamps will increase the proportion of LED street lamps by about 6%.

According to the above assumptions, the street lamp energy-saving renovation will be carried out. By the end of the “Twelfth Five-Year Plan” period, the number of LED light source street lamps in Guangxi municipal roads will reach about 30%, and the power ratio will reach about 16% (according to the average power of high-pressure sodium lamps, 250W, LED lights average). Power 100W meter).

4 Guangxi municipal street lamp energy-saving renovation promotion application LED light source benefit analysis 4.1 Energy-saving benefit analysis 4.1.1 Incremental street lamp using LED light source lamp energy-saving benefit analysis According to the third part analysis, to the end of the “Twelfth Five-Year Plan”, the total number of municipal street lamps in Guangxi will reach 111.27 Wan Hao, the new street lights reached 352,700. The newly added street lamps are mostly street lights installed in urban development and expansion, and the added roads are generally fast roads or main roads. According to 70% new street lamps (about 246,900 baht), an incremental promotion scheme for LED energy-saving light sources will be adopted. If the energy-saving transformation is not carried out, the installed street lamps are generally high-pressure sodium lamps with high power. According to the survey, basically, the high-pressure sodium lamps of 400W, 250W and 150W are mainly used, and the proportions corresponding to the number are 20%, 50% and 30% respectively. With 365 days of annual lighting, the daily driving time is 10 hours, and the actual power loss of the high-pressure sodium lamp is calculated as 1.3 times of its rated power. The annual power consumption is 10,000 kWh.

5271.932 million kWh.

The annual power consumption of the new high-pressure sodium lamp is: 937.324+14644.256+5271.932=29288.513 million. If 70% of the newly added street lamps are used for the promotion of municipal street lamps, the energy-saving transformation of LED energy-saving light sources is used. LED light source. Replace the sodium lamp with the LED light source lamp. Generally, replace the 400W high-pressure sodium lamp with a 160W LED lamp, replace the 250W high-pressure sodium lamp with a 100W LED lamp, and replace the 150W sodium lamp with a 60W LED lamp. The actual power loss used by the LED lamp is calculated as 1.1 times of its rated power, and the power consumed after the energy-saving transformation is: the annual power consumption of the newly added LED lamp is tens of millions of hours.

It can be seen from the above results that the promotion of 70% of new municipal street lamps in Guangxi will be improved by using LED energy-saving light sources, which will save electricity compared with ordinary sodium lamps. This will reduce the total electricity consumption of municipal street lamps in Guangxi by 39% in 2011. 4.1 .2 The inventory of high-pressure sodium lamps is transformed into LED light source street lamps. Energy-saving benefit analysis According to the promotion and transformation plan of Part 3, to the end of the “Twelfth Five-Year Plan”, the high-pressure sodium lamps for the 250W and above of the municipal street lamps in Guangxi (a total of about 327,000 盏, 400W The transformation rate of sodium lamp is about 100,000 baht and 250W high-pressure sodium lamp is about 227,000 盏. The transformation rate is about 20%, and the number is about 65,400 盏 (including 400 watts of high-pressure sodium lamps, about 20,000 watts, and 250 watts of high-pressure sodium lamps).

Similarly, the lighting is turned on for 365 days per year, the driving time is 10 hours per day, the actual power loss of the high-pressure sodium lamp is 1.3 times of the rated power, and the actual power loss of the LED lamp is calculated as 1.1 times the rated power.

37.96 million kWh.

It can be seen from the above results that after the energy-saving renovation of the stock street lamp, the LED light source lamp saves electricity by 9181.575-3107.61=6073.965 million times than the high-pressure sodium lamp. 0.61 billion kWh. It is equivalent to reducing the total electricity consumption of municipal street lamps in Guangxi in 2011 by 12%. In summary, by the end of the “Twelfth Five-Year Plan” period, 70% of the newly added street lamps use LED light source street lamps, and 20% of the 250W or more stocks of high-pressure sodium lamps are implemented. LED light source transformation, annual energy saving 1.94 + 0.61 = 255 million kWh, equivalent to reducing the total electricity consumption of municipal street lamps in Guangxi in 2011 by 52%. After conversion, equivalent to saving 85,400 tons of standard coal.

4.2 Analysis of investment payback period 4.2.1 Analysis of investment and payback period of incremental street lamps According to the route selection plan for energy-saving transformation of Guangxi municipal street lamps, to the “Twelfth Five-Year Plan”

At the end, 70% of the new part of Guangxi's municipal streetlights are in principle using LED street lights, totaling about 246,900 baht, which will save about 194 million kWh of electricity annually. Calculated according to the electricity fee of 0.85 yuan / kWh, the annual electricity cost can be saved by 164.9 million yuan. The calculation formula is: For incremental street lamps, the construction investment difference between each LED lamp and high-pressure sodium lamp is about 3,200 yuan. The calculation formula is: increase investment = LED lamp investment price - high pressure sodium lamp investment price = 5000-1800 = 70% of the new part of the total 246,900 lamps use LED lights to increase investment = increase investment part, can save through annual The electricity bill is constantly offset.

Then, the increased investment can be recovered within 4.8 years. The calculation formula is: It can be seen that for incremental street lamps, although the initial installation cost of LED energy-saving street lamps is much higher than that of conventional street lamps, the investment can be recovered within 4.8 years through high-efficiency power saving. The service life of LED energy-saving street lamps is generally about 8-10 years. Therefore, in the application of new municipal roads, the profits from the promotion of LED light sources are abundant.

4.2.2 Analysis of the investment and recovery period of the stock street lamp renovation According to the route selection plan for the energy-saving transformation of Guangxi municipal street lamps, to the “Twelfth Five-Year Plan”

At the end, the transformation of the stock of Guangxi municipal street lamps reached 65,400, and the investment for each renovation was about 5,000 yuan. The total investment required was about 327 million yuan. The calculation formula is: According to the energy-saving analysis data of the LED high-pressure sodium lamp, it can be seen that the annual energy saving of the stock street lamp can be 0.61 billion kWh, equivalent to 51.85 million yuan of electricity. From this, it can be calculated that the investment recovery period for the stock street lamp transformation is 6.3 years, and the calculation formula is: (year) due to the different power of LED lamps, different manufacturers, different power supply methods, etc., the installation and installation prices of LEDs will be slightly different. But the difference is not big. Generally speaking, for the stock street lamps, the energy-saving street lamps such as LEDs are used to renovate the conventional street lamps, and it is generally necessary to recover the conversion cost through the power saving revenue in 5-10 years.

Therefore, in the municipal road reconstruction, the profit obtained by replacing the high-pressure sodium lamp source with the LED light source is rich. From an economic perspective, LED lights are suitable for use in Guangxi municipal roads.

4.3 Other Benefit Analysis 4.3.1 Protecting the environment, reducing pollutant emissions Saving electricity and reducing power generation indirectly reduces the use of coal and reduces the emission of various harmful gases to protect the environment. It can be equivalent to reduce the use of standard coal by 0.330 kg, reduce the use of purified water by 4.000 kg, reduce the emission of C2 (carbon dioxide) by 0.780 kg, reduce the emission of SO2 (sulphur dioxide) by 0.009 kg, and reduce the emission of NOx (nitrogen). Oxide) 0.002 kg, TSP (total suspended solids) 0.00335 kg. The street lamp energy-saving transformation saves a total of 255 million kWh, which is equivalent to reducing the use of standard coal by 84,000 tons, reducing the use of purified water by 1.02 million tons, reducing emissions of C2 (carbon dioxide) by 199,000 tons, and reducing emissions of S2 (sulphur dioxide) by 2,295 tons. To reduce emissions of 510 tons of NOX (nitrogen oxides) and 854 tons of TSP (total suspended solids). It can be seen that energy-saving renovation of street lamps can reduce the burning of large amounts of coal and oil for the country every year, rational use of national limited energy resources and reduction of atmospheric environmental pollution, and will play an active role in benefiting mankind, contributing to society, benefiting the country and benefiting the people, and is immeasurable. value.

The nuclear method is more appropriate. The theoretical examination can be carried out by means of unwinding, and more than half of the assessment content is based on the specific design in the project, or the application problem model based on the specific design examples. In addition to the basic experimental dimension measurement, shape and position error measurement, surface roughness measurement, thread measurement, and geometric accuracy comprehensive testing of this course, the practice will introduce the content of the innovation competition into the practice link, requiring students to The subjects involved in the mechanical innovation competition give their own ideas and give the tolerance and precision design parts.

3 Play the leading role of the students in the classroom The students of the independent colleges are less solid in the use of theoretical knowledge than the students of the two or more institutions. At the same time, the students of independent colleges are more active. According to this reality, it is especially important for students to play their own subjective initiative in the classroom. In the process of teaching, teachers should make detailed, slightly, fast and slow adjustments of knowledge points according to the students' reflections. A particularly good method is to use the heuristic teaching when teaching in the classroom, and to introduce the knowledge points to some reasonable engineering cases, so that students can analyze and associate with the course to understand and get through the knowledge to be learned. From the beginning to the end, students are allowed to play a leading role in the master. Discussion teaching is also a good method. Because the theory and practice of this course are particularly strong, it is more difficult for students to learn. Therefore, the teacher guides the students to fully discuss after the case is taught, especially the precision design part. For example, when teaching the tolerance level table, the teacher should guide the students to compare the vertical and horizontal values ​​of the value table, and draw relevant conclusions and combine the engineering examples to let the students discuss the selection principle of the tolerance level in the actual production. And the reason. If necessary, the students can visit the processing workshop in real time. Through discussions with the workers' masters, it is understood that the selection of the tolerance level is not as high as possible, and the lower the better, but the economic and technical.

The leadership of the students in the learning process is also reflected in this aspect. In the experimental class of this course and each chapter, the process of the teacher's reasonable knowledge through the well-designed homework and the students' reasonable answering process is completed. For the basic experiments in the experimental course, such as the measurement of the hole axis, the students are required to perform a group of 5-8 people and fill in the experimental report. On the basis of the teacher's key demonstrations, such as the three-coordinate measuring instrument, which needs to be measured by precision instruments, students can fully utilize the subjective initiative to consult relevant technical fields and understand the current advanced measuring instruments and technologies to achieve their vision.

4 Conclusion is strong. In particular, there are many abstract terms and definitions involved in the course of the course, students should not understand, teachers are not easy to teach. Therefore, it is very necessary to discuss the teaching methods of this course. This paper expounds the two practicalities of students and teachers, and it has certain practical value and feasibility to use guided, heuristic and discussion-based teaching as a breakthrough and practical teaching methods.