Fixed LEDs in lamps- how long do they last?

The service life of LEDs: comparison and progress

The service life is generally expressed in operating hours, which is a common method for determining the longevity of light sources. LEDs are known to last significantly longer than conventional incandescent or halogen lamps.

Manufacturers typically state a service life of around 20,000 to 50,000 hours. These impressive figures are the result of the technological advances that have been made in LED development. To understand the significance of these operating hours in an everyday context, a simple

example calculation: A LED lamp, that is used for an average of 3 hours per day would last for around 18 years with a service life of 20,000 hours. If the same lamp is operated for 50,000 hours, it could last up to 45 years. This is a huge advantage over conventional incandescent lamps which only last around 1,000 hours on average and halogen lamps, which last around 2,000 to 4,000 hours.

Comparison with conventional light sources

The long service life of LEDs is a major reason why they are increasingly replacing incandescent and halogen lamps. halogen lamps lamps. While a conventional light bulb burns out relatively quickly and has to be replaced frequently, the use of LEDs significantly reduces maintenance costs. This reduction in replacement frequency is not only practical, but also saves costs in the long term.

Technological advances and efficiency

The impressive lifespan of LEDs is the result of numerous technological advances. LEDs utilize semiconductor technology, which enables a more efficient conversion of electricity into light compared to traditional methods of light emission with incandescent bulbs. While an incandescent bulb produces light through the heating effect of a tungsten filament and loses a lot of energy as heat, LEDs work cooler and more efficiently.

Long-term reliability

In addition to their long service life, LEDs also offer consistent light quality over their entire operating time. With many conventional lamps, the luminous efficacy over time, whereas LEDs tend to maintain their brightness over a much longer period.

The failure rate is also lower with LEDs, making them a reliable choice for applications where continuous lighting is crucial, such as in industrial environments or public facilities.

Economic and environmental benefits

The long service life of permanently installed LEDs not only brings economic benefits through reduced maintenance and replacement costs, but also environmental benefits. Less frequent replacements mean less waste and lower resource consumption. This makes LEDs a more environmentally friendly option that can contribute to a sustainable lighting strategy.

"To extend the service life of permanently installed LEDs, make sure that they do not overheat. Permanently installed LEDs are sensitive to heat and high temperatures can drastically reduce their service life. It is therefore important that the LEDs are cooled properly, e.g. by using heat sinks or fans."

Degradation of LEDs: causes, effects and countermeasures

Degradation is a term used in many technical and scientific fields and generally describes the process of deterioration or gradual degradation of material properties, performance or efficiency. 

In relation to LED technology it refers to degradation refers to the reduction in light output and efficiency of LEDs over time. This process is unavoidable, but its speed and extent can be influenced by various factors.

Degradation of LEDs

In LEDs, degradation occurs mainly in the form of a decrease in luminous efficacy. This decrease is often referred to as luminous flux maintenance or lumen maintenance and is expressed as a percentage of the original luminous efficacy. For example, a typical degradation value could be 70% of the original brightness after 50,000 hours of operation, often expressed as L70. This means that the LED still delivers 70% of its original brightness after this operating time.

Causes of degradation

1. Thermal stress: Excessive heat is one of the main reasons for the degradation of LEDs. Although LEDs are more efficient than traditional light sources, they still generate heat that needs to be dissipated. Poor heat dissipation can lead to overheating, which damages the LED materials and reduces the light output.
2. Electrical load: Heavy or fluctuating current loads can affect the service life and efficiency of LEDs. A constant and stable power supply is crucial for minimizing degradation.
3. Environmental conditions: Humidity, extreme temperatures and chemical influences can attack the materials of the LED and the associated components and lead to faster degradation.
4. Material quality: The quality of the materials used has a significant influence on the degradation rate. High-quality LEDs with robust materials generally show slower degradation compared to inferior products.

Effects of degradation 

Degradation has a direct impact on their performance and efficiency. As degradation increases, not only does the brightness decrease, but color shifts can also occur, affecting the quality of light. This can be particularly critical in applications where constant lighting conditions are required, such as in industrial environments, medical facilities or art galleries.

Measures to reduce degradation

1. Good thermal management: The implementation of effective cooling systems or techniques can keep the temperature of the LEDs low and thus slow down degradation.
2. High-quality materials: The use of high-quality LEDs and components can significantly reduce the rate of degradation.
3. Stable power supply: A constant and clean power supply prevents electrical overloads and protects the LED components.
4. Protection against environmental influences: Suitable housings and protective coatings can protect LEDs from harmful environmental influences and extend their service life.

Factors and methods for calculating LED service life

The LED service life is usually specified in operating hours and describes the period during which the LED can maintain a certain output or brightness. This calculation is based on several factors and tests to ensure that the LEDs function reliably under real conditions. Here are the most important steps and factors that are taken into account when calculating the LED service life:

1. lumen maintenance (luminous flux maintenance): The lifetime of an LED is often defined as the time until the luminous efficacy has fallen to a certain percentage of the original value. Typical measured values are

1. L70: The time until the LED reaches 70% of its original luminous efficacy.
2. L80: The time until the LED reaches 80% of its original luminous efficacy.

For example, L70=50,000 hours means that the LED still provides 70% of its original brightness after 50,000 operating hours.

2. test conditions: LEDs are tested under standardized conditions to obtain consistent and comparable results. These tests include:

1. Temperature: LEDs are tested at different temperatures to measure their performance under realistic operating conditions.
2. Operating current: The current at which the LEDs are operated is kept constant during the tests.
3. Ambient conditions: Tests take into account environmental conditions such as humidity and air pressure.

3. accelerated service life tests: Since it is impractical to test LEDs over their entire lifetime, accelerated tests are used. These tests increase the operating temperature and current to accelerate the ageing process. The results of these tests are then extrapolated to estimate the lifetime under normal conditions.

4. failure rate and reliability: In addition to luminous efficacy, the failure rate of the LEDs is also considered. This refers to the probability that an LED will fail completely due to a technical defect. Statistical methods such as the Weibull distribution are used to model the failure rate over time.

5. manufacturer specifications and certifications: Manufacturers often state guaranteed lifetimes based on their internal tests and models. Certifications from independent testing organizations can provide additional assurance that the stated lifetimes are reliable.

Example of a calculation 

A manufacturer could operate an LED at 25°C room temperature with an operating current of 350 mA and find that the LED retains 95% of its original brightness after 10,000 hours. 

Using mathematical models and accelerated tests at higher temperatures, it could be extrapolated that the LED still has 70% of its brightness after 50,000 hours under normal conditions (L70).

Factors influencing the actual service life of LEDs

The actual service life can be influenced by a variety of factors that go beyond the simple specification of operating hours. Switching cycles, the number of operating hours and the ambient temperature play a significant role here. These factors can significantly influence the performance and longevity of LEDs and should be taken into account when selecting and installing LED lighting.

1. switching cycles

Definition and influenceSwitching cycles refer to the number of times an LED is switched on and off. Each LED has a limited number of switching cycles it can handle before its performance is affected.

Influence on service lifeFrequent switching on and off can lead to thermal stresses in the LED as it heats up and cools down each time. These thermal cycles can stress the internal components and lead to premature failure. LEDs are generally more resistant to switching cycles than conventional light bulbs. Nevertheless, extremely frequent switching on and off, for example in applications such as motion detectors or flashing lights, can shorten the service life.

Manufacturer informationMany manufacturers state that their LEDs are designed for a certain number of switching cycles. This can range from a few thousand to several million cycles, depending on the quality and design of the LED.

2. number of operating hours

Definition and influenceThe number of operating hours refers to the total time an LED spends switched on. This is the primary factor that determines the lifetime of LEDs and is typically specified by manufacturers.

Influence on service lifeThe service life of an LED is often described in terms of lumen -maintenance, e.g. L70 (the time until the LED reaches 70% of its original luminous efficacy). A longer operating time means a higher cumulative load on the LED components. LEDs that are operated constantly for longer periods generally have a longer service life compared to those that are switched on and off frequently.

Practical exampleAn LED that is operated for an average of 3 hours per day has a much longer expected life than one that is operated 24 hours per day. This means that the same LED will last longer in a household than in an industrial application where it may light up around the clock.

3. ambient temperature

Definition and influenceAmbient temperature is the temperature of the air around the LED during operation. LEDs are sensitive to high temperatures as they can directly affect performance and lifetime.

Influence on service life:

High temperaturesIf LEDs are operated at high ambient temperatures, this can lead to overheating. Overheating accelerates the degradation of the LED materials and reduces the luminous efficacy more quickly.

Low temperatures: Low temperatures are generally less harmful to LEDs and can even extend their lifespan. LEDs work more efficiently and with less heat generation at cooler temperatures.

Thermal managementEffective heat dissipation is crucial to maximize the lifetime of LEDs. This can be achieved through the design of the LED luminaire, heat sinks and other passive or active cooling methods.

Manufacturer specificationsMost manufacturers test their LEDs at standardized temperatures, typically 25°C. These tests provide baseline data, but the actual lifetime may vary if the LEDs are operated in warmer or colder environments.

Reasons for LED failures and ways to replace LED lamps

LEDs can break down, although they have a much longer lifespan compared to conventional incandescent and halogen lamps. Various factors can cause an LED to fail:

OverheatingOne of the most common causes of LED failure is overheating. If the heat is not dissipated effectively, the internal components of the LED can be damaged. This can be caused by inadequate thermal management, lack of ventilation or high ambient temperatures.

Electrical overloadVoltage spikes or current fluctuations can damage the electronic components of the LED. This can be caused by faulty power supply units, improper wiring or electrical faults in the mains supply.

Quality problemsInferior LEDs or poor workmanship can also lead to premature failure. High-quality LEDs from reputable manufacturers generally have a longer service life and are less susceptible to defects.

Mechanical damagePhysical impacts such as shocks, vibrations or improper handling can damage LEDs. The connections and solder joints within the LED are particularly susceptible.

DegradationEven if LEDs work reliably over long periods of time, they are still subject to a natural ageing process. The light output gradually decreases and color changes may occur. Over time, this can lead to the LED being considered "broken", even if it is still working.

Can LED lamps be replaced? 

Whether and how LED lamps can be replaced depends on the design of the luminaire and the type of LED. There are basically two main types of LED lamps: replaceable LED lamps and permanently installed LED lamps.

Replaceable LED light sources

1. Easy replacement: Many LED lamps are designed so that they can directly replace conventional incandescent or halogen lamps. These LEDs have standardized bases (e.g. E27, GU10) and can be easily replaced by screwing or plugging them into the existing socket.
2. Advantages: Replacement is simple and requires no special tools or specialist knowledge. In addition, defective or obsolete LEDs can be replaced quickly and inexpensively.

Permanently installed LED lights

1. Complexity: Replacing permanently installed LEDs is usually more difficult as the LEDs are integrated into the luminaire. This often means that the entire luminaire has to be replaced if the LEDs fail.
2. Advantages: Permanently installed LEDs enable more compact and efficient designs. They often offer better heat dissipation and a longer service life as they are specially optimized for the respective luminaire.

Five tips for extending the service life of your LED light sources

1. ensure good heat dissipation

Why important: Overheating is one of the main causes of premature LED failure. Effective heat dissipation can keep the temperature of LED light sources low and extend their service life.

How to implement: Use luminaires that have been specially developed for LEDs and have good heat sinks or ventilation systems. Make sure that the LED lamps are installed in well-ventilated areas to facilitate heat dissipation. Regularly clean dust and dirt from the heat sinks and ventilation slots to maintain the efficiency of heat dissipation.

2. ensure a stable power supply

Why important: Voltage fluctuations and electrical overloads can damage the internal components of the LEDs and shorten their service life.

How to implement: Use LED-compatible dimmers that ensure an even power supply and do not affect the service life of the LEDs. Install surge protection devices to protect the LEDs from sudden voltage spikes. Make sure that the electrical installations in your home or business are proper and safe.

3. avoid frequent switching on and off

Why important: Every time an LED is switched on or off, it is exposed to thermal stresses that can affect its lifespan.

How to implement: Avoid switching LEDs on and off unnecessarily often. Leave them on if you only leave the room for a short time. Use motion detectors and timers to optimize the switching on and off of LEDs and reduce the number of switching cycles. For areas where frequent switching on and off is unavoidable, choose LEDs that are designed for many switching cycles.

4. consider environmental conditions

Why important: Extreme temperatures, high humidity and aggressive environmental conditions can affect the performance and service life of LEDs.

How to implement: Install LEDs in environments that are within the manufacturer's recommended temperature range. Avoid using LEDs in humid or corrosive environments unless they are specifically designed for this (e.g. IP-protected LEDs for outdoor areas ). Protect LEDs from direct sunlight and other extreme weather conditions.

5. select high-quality LEDs and accessories

Why important: High-quality LEDs and components generally offer better performance and a longer service life.

How to implement: Invest in LEDs from reputable manufacturers that are known for their quality and reliability. Look for certifications and seals of approval that confirm the quality and service life of the LEDs. Only use compatible power supply units and drivers that are specially designed for the respective LEDs.

Conclusion - How to do everything right!

The service life of LED light sources can be extended considerably by taking simple measures. Good heat dissipation, a stable power supply, avoiding frequent switching cycles, suitable ambient conditions and the selection of high-quality products are crucial. By following these tips, you will benefit from long-lasting, efficient and reliable LED lighting that saves costs and protects the environment in the long term

If you are still undecided about how you want to implement the lighting, please arrange an appointment with the lighting designers from skapetze®, for a personal consultation and the development of a individual lighting concept and the development of an individual lighting concept.

You are also welcome to visit us on site in Simbach am Inn at our light studio come and visit us.

If you already have a concrete idea of how the lights should look in your home, we can help you turn this idea into reality - our in-house workshop makes it possible.