Three ways to reduce the cost of solar LED street lamps

Development status of solar LED street lamps in China

At present, one of the main problems of solar LED street lamps is the high cost. No matter which aspect, at least to ensure the correct requirements, one is to ensure eight hours, and then the normal work of rainy days, the quality is three years, and the light is 10% per year, according to the basic requirements is less than 30% of luminous flux To ensure the basic implementation of the configuration, based on a large amount of theoretical and practical data, the experience is that in the northern region is 4, in the Qinghai region of Tibet is 3, that is, power and battery. For batteries and controllers, there is a proportional relationship between them.

A contradiction is that the power of the light source determines the system architecture of the solar energy. For example, like a typical configuration, only this configuration can meet five rainy days and eight hours a day. All sun versions and this are basically 1:4, so the control on the battery is 10. The power supply cost of solar energy is 320-346 yuan per watt, because the price is 4800~5200 yuan per set (the price of Beijing basic bidding in 2007~08).

To reduce costs, there are only three ways. The first is to optimize the design to improve efficiency, the second is to change the configuration to reduce costs, and the third is to improve the light efficiency and reduce power.

First, the feasibility of reducing costs one by one

1. The first is to optimize the design. For solar cells, from 1980 to 2005, the efficiency has increased by 3 to 4%, so the room for improvement is very small. It is expected to be 1 to 2% within 3 years, and it is good to reach 15 to 16%. For the efficiency of the controller, the domestic excellent has reached 0.975, and the foreign one is 96%. In the past two years, the improvement space is only 2~3%, which is impossible to reach 99% and 100%. For the efficiency of the luminaire, the power used for solar energy is low power, below 50W. After the domestic 50W sodium lamp test is 60~70%, energy-saving lamps, high-pressure lamps and metal lamps, because there are energy consumption of electronic discriminators, most of them are electronic resolver damage in the bad time, and LED lamps are such light sources. Except for.

2. For several low-cost configurations, when the resource cost is low, the solar cell configuration is reasonable, but the experimental value is very small. When the person leaves the lighting, the part of the electricity storage is small, and the lighting is less than eight hours per day. The second is that the solar cells are small, and the controlled batteries are also small and cannot be guaranteed every day. The third aspect is that the solar cell is small and the battery is large. Although the first 10 days can guarantee that the day will not be able to generate electricity, it will be bright, but in fact it is the electricity of the battery. The fourth is that the power is high and the configuration is low. Although the light is on, it cannot be guaranteed for eight hours.

3. The space for system design is small, and the low-cost control affects the quality. The conventional light source will increase in the past two or three years, and the conclusion is that the cost of the solar system is greatly reduced by conventional technology. So what is the design idea? It is to improve the light efficiency, which is the third option just mentioned. Increasing the light efficiency is equivalent to reducing the power. Lowering the power is equivalent to reducing the cost. Therefore, improving the LED light efficiency is another way to reduce the cost. From the perspective of network engineering, on the basis of 70 lm/w, LED light efficiency is increased by 15%, and solar energy cost can be reduced by 10%. Increasing the light effect has little effect on the system, because the quality of the lighting will not be reduced, the total optical drive volume is almost the same, the cost of solar energy is significantly reduced, the battery is less, and the battery support, maintenance, and battery panels are all reduced. As long as the cost of high-efficiency LEDs is controlled, it accounts for 10% to 15% of the total cost. If you want to select the LED, the same light efficiency = the same lighting power, that is 1W = 320 yuan, you must reduce this power! According to the different LEDs tested at home and abroad, although the luminous efficiency is 100 lm/W, the strain illuminance is 30~40%, which is called the value.

Second, with efficient LEDs, can you make a good fixture?

The efficiency of the LED should be greater than 100 lm/W, and the efficiency of the constant current circuit should be greater than or equal to 90%. It is better to select the boost type because the efficiency of the step-down (DD311 DD322) chip is 80% or more. Several new boost models are available in the United States, with chip efficiency greater than 93%. In addition, it is necessary to reduce the backlight loss, because many lenses are poor now, and the light-transmitting materials are different. Some lenses have better light transmittance and some have poor light transmittance.

Now there are only three kinds of efficient LEDs, 6~8 hours, lithium battery batteries, the smallest one can also be made into an LED, which can be loaded in one minute. The specifications and prices commonly used in China in 2008 are 35W. For development opportunities, there are two. First, the price of solar panels has dropped sharply, from 30 yuan in 2007 to 10 yuan now, especially before October last year; the second development opportunity is The domestic LED light efficiency is close to 100 lm/w, so the price drop is around 25% every year.

Third, LED street light tenders should be quoted by power

Finally, a suggestion, the future street lamp tender should be quoted by power. There is also the development of products to find out its characteristics. These applications of the solar system mentioned above are encouraging and encouraged development effects. Then there is the need for technical support for solar LED street lights, respect for intellectual property, and the commercial value of products before they can achieve commercial results.