How to evaluate whether an LED lamp is energy-savi

  • Detail

How to evaluate whether an LED lamp is energy-saving

if you are not professional, how can you gain respect and status? But everyone is used to this. As Chen Danqing said: the most terrible thing is not like this. The most terrible thing is that everyone recognizes it. We felt that we couldn't recognize it, so we began the endless road of science popularization, and we came to the present as soon as we left

nowadays, the industry, including more and more official account and marketing of many enterprises, are popularizing Lighting Science. The downstream industries we cooperate with gradually feel that lighting is very important. We are not ashamed to say that we are very proud to have such a positive impact on and promote the industry in a new and mobile Internet way

the lighting industry has never been so prosperous before. Needless to say, under the general environment and trend of energy conservation, emission reduction and green environmental protection, it is the industry consensus and general trend for led to become the mainstream light source of lighting. As for the street talk in the consumer market, when it comes to lighting, although most of them know a little, everyone is already familiar with LED. This half is naturally due to the strong support and promotion of the government, and the other half is also due to the advantages and charm of LED technology itself

in the eyes of the general public, as a new lighting technology, LED has basically been equated with energy saving. However, are led lamps really energy-saving? How to evaluate whether an LED lamp is energy-saving

luminous efficiency of light source

led (LightEmittingDiode) is a light-emitting diode, which is a solid-state semiconductor component that can convert electrical energy into visible light. Just like the principle of thermal radiation behind traditional incandescent lamps and halogen lamps, fluorescent lamps, mercury lamps, sodium lamps and metal halide lamps adopt the principle of gas discharge, led itself represents a technology, a principle of light emission

luminous efficiency of light source (often referred to as luminous efficiency): the ability of the illuminant to convert electric energy into visible light, measured by the ratio of luminous flux to power, and the unit is lm/w

the efficiency comparison of common light source products in the market corresponding to various light-emitting principles is shown in the following table:

from the above table, it can be seen that led technology, as a new lighting source, has a certain progressiveness over traditional light source technology. But even so, the light efficiency range of LED technology itself is very wide. It is inaccurate to say that led light sources are more energy-saving than other light sources in general. It is just as unscientific to say that Chinese people are romantic, Chinese people are hardworking, and Japanese people obey rules. When we get along, we have to see how each other is. French, Chinese and Japanese use LED products as well

in fact, it is far more than what technology and light source are used to judge whether a lamp is energy-saving

electrical energy efficiency

in addition to incandescent lamps and line voltage halogen lamps, the lighting of other light sources need to be equipped with lighting appliances. Lighting appliances also have the problem of electric energy utilization, that is, the ratio of electric energy used by appliances to drive the light source to emit light. Without considering harmonics, the power factor λ COS is usually used φ To express. It doesn't matter if you don't understand these. In short, the efficiency of lighting appliances usually depends on the power factor index

most brand manufacturers will also provide the system efficiency parameters of electrical appliances on the product sample book or single page, as shown in the following figure. Our designers can ask the manufacturers to provide relevant parameters

lamp efficiency

lamp efficiency is easy to understand. In short, it is the ratio of the light coming out of the lamp to the light emitted by the light source in the soil hardened by the lamp under standard conditions, which is usually expressed in lor

lor = luminous flux emitted by the lamp/luminous flux of all light sources in the lamp

for example, for an ordinary 3*18w lamp panel, the total luminous flux of the light source is 3600lm. If the measured luminous flux of the lamp is 1800lm, we say that the efficiency of the lamp is 50%

lamp efficiency

regardless of the light distribution and light utilization of the lamp, and whether the designer uses the lamp reasonably in the space (if the lighting design process is divided into three parts: light selection, light distribution and light consumption, our discussion today is limited to the "light selection" part), evaluate whether a lamp is energy-saving, It is necessary to combine the above three aspects to get the lamp efficiency:

lamp efficiency = luminous flux emitted by the lamp/(light source power + electrical loss) = luminous flux emitted by the light source *lor/(light source power + electrical loss)

is the LED lamp energy-saving

after clarifying the standards for evaluating whether a lamp is energy-saving or not, we can judge the advantages and disadvantages of these two lamps

take a brand of 3*14w grille lamps as an example. When it uses three 14w/1200lm lamps and is equipped with one single tube 14W ballast and one double tube 2*14w ballast, the system power is 18 + 32.5 = 50.5w. The efficiency of grille lamp lor = 70%, then the efficiency of lamp is 3600 * 70%/50.5w = 49.9lm/w

at this time, as long as the lamp efficiency of the corresponding 3*14w replacement LED lamp is higher than 49.9lm/w, we can say that it is energy-saving compared with the original grille lamp

examples are as follows:

when we design the "light selection" link, we mainly choose the appropriate light source, supporting the appropriate electrical appliances, and the appropriate lamps. Energy efficiency is one of the important aspects

when considering energy conservation in the design scheme, we can't just look at what technology and light source are used, that is to say, don't think that led is bound to save energy, but rather look at the actual parameters of light sources, electrical appliances and lamps. The best way is to review and measure physical samples, which can best see the problem

from this, we can also see that how much is a watt of LED, which is very popular now, is actually unreasonable, because owners buy Lamps and lanterns with "light", not "power". In yuan/watt, but compared with other lightweight materials, it is still more advantageous to measure led. It is likely to buy LED products with light efficiency, but there seems to be signs of warming up, which are very low and not energy-saving. If we only consider the light output of lamps, perhaps the indicator to measure the economy is yuan/kilolumen, that is, how much money to buy preventive measures has the following two points: 1. How much light is produced. Whether these lights are used or not is another matter

Copyright © 2011 JIN SHI