Ever since they were first introduced, LEDs have been developed and improved upon over the years so that they are one of the best lighting solutions. Although they have numerous benefits, this does not mean that they should be considered as the best lighting solution for every situation and environment.
In order to determine if LED lighting is really the best choice for you and a specific application, you need to carefully weigh up both their advantages and disadvantages.
What Are The Benefits of LED Lighting?
Instant Switch On
Let’s start with a nice and simple benefit of LEDs – unlike energy-saving incandescent and halogen lighting fixtures, that can take a long time to light up fully – especially in colder temperatures; LEDs instantly switch on. This is particularly advantageous for lighting applications like car and other vehicle brake lights.
This is one of the most commonly understood benefits of switching to LEDs from more traditional halogen or incandescent lighting. Thanks to the fact they are free from mercury and other toxic materials, LEDs are lot kinder on the environment. There are even plans to switch the solders containing lead (that are used to install LEDs on circuit boards).
Many outdoor LEDs are also available in solar-powered versions, such as with solar path lights, which means they cost nothing to run once you’ve made the inital purchase.
Highly Energy-Efficient and Lower Energy Consumption
Another common benefit, one that follows on nicely from the above is the fact that LEDs are incredibly energy-efficient forms of lighting. Furthermore, they also consume less power than alternative forms of lighting, which means switching to LEDs could potentially save you hundreds, even thousands in electricity bills.
Lifespan of LEDs
This is yet another advantage that often drives people and organizations to invest in LED lighting. Generally speaking though, although solid state varieties of LEDs do last an incredibly long time and have a sturdy construction, the figures used to describe LED lifespan can be very misleading.
For instance, it is true that LEDs have a longer lifespan than say, incandescent bulbs that only last for 1,000 hours. Now on the surface of it, it would seem that with most LEDs being able to last for anything between 50,000 and 100,000 hours, that LEDs are definitely longer lasting.
However, as noted these numbers can be misleading as they do not take into consideration the fact that just like any other type of lighting, LED performance degrades in time. The causes of degradation includes the LED temperature and operating current.
At the moment, we do not have a standardized way of defining an LED’s lifespan. However, there are some experts who suggest it should be determined by the amount of time it takes for the output of an LED to fall below a certain percentage of its original output value.
Lower To No Maintenance
Following on from the above, thanks to LEDs increased lifespan, you do not to regularly replace bulbs and other lighting fixtures if you are using them, meaning that you can make considerable savings. A further advantage of the low to no maintenance involved in LEDs means that they are particularly practical when lighting is required in hard to reach areas and locations.
On the other hand though, it may be necessary to regularly carry out electrical checks and clean those areas. If that is the case, the lights could be replaced at the same time, meaning that low maintenance is not really a viable advantage.
Are LEDs Cost Effective?
Manufacturers of LEDs are constantly working on trying to reduce the cost of producing these lights, while trying to increase the output of LEDs.
On the plus side, when it comes to the cost of LEDs, it is worth taking on board the fact that although the upfront cost of LED lighting is rather expensive, it could save you money in the long run. Remember, LEDs are energy-efficient and do not require as much power to operate them as other light sources. They also do not require as much maintenance.
A major downside that many people point out about LEDs is the fact that while they don’t consume as much power and are highly-efficient; they are not nearly as bright as the alternatives.
When you consider, for example, that a 60 watt incandescent bulb that has an energy-efficiency rating of 20 lumens per watt can produce 1,200 lumens; a 1 watt LED with 30 lumens per watts efficiency can only produce 30 lumens. Therefore it would take 40 of these LEDs to provide the same level of brightness as that one incandescent bulb.
The Two Sides Of The Heat Story
It is a known fact that LEDs do not actually produce heat the same way as incandescent bulbs do, as infrared radiation. Therefore, LEDs do not have the same problem of being too hot to touch that the incandescent bulbs do. As there is no IR radiation generated by LEDs, they can be installed into locations and areas where conventional sources of lighting that emitted heat would cause problems such as illuminating textiles or food.
That being said, LEDs still produce a lot of heat internally at the junction of the semiconductor. As a result, LEDs tend to have a wall-plug efficiency level (calculated by taking the optical power out and dividing it by the amount of electrical power going in) that is anything between 5 and 40%. As a result, that means that around 60 to 95% of the power going in is lost when it is converted into heat energy.
The temperature at the junction in an LED unit will rise, causing changes to the characteristics of the LED, if there is no suitable and efficient heat sinking and thermal management. As LEDs are driven way beyond the current they are rated for, it could mean that this temperature rises to the point where irreversible damage is done to the unit and anything it may be connected up to.
Various Benefits and Drawbacks with Regards To Color
One of the biggest areas where there are many benefits and drawbacks to using LEDs is color. On the one hand, LEDs are available in a wide range of vibrant and bright colors and there are now even white LEDs (more on that a little later) out there.
Further to this, units that use LEDs of various colors, such as RGB for example, it is easy to create a vast array of colors and these can all be dimmed with little to no hassle. When RGB LED units are used, they make it possible for a greater number of different colors to be used than traditional white light sources. This is an especially big advantage when it comes to applications like LCD back lighting.
Inconsistency of White LEDs
However, as good as the above is, it is important to highlight the fact that when it comes to white LEDs there is a lot of inconsistency. Though, manufacturers are working hard to narrow their binning ranges. One of the main issues is the fact that often white LEDs that have the same color temperature or equivalent have noticeably different tints.
Color Mixing and RGB LEDs
A further drawback of LEDs related to color is the fact that the characteristics of LEDs can change from device to device and depending on the current, temperature and how long into their lifespan they are. As a result, in RGB LEDs, the individual LEDs often change at very different rates, meaning that there can be a variation in lighting intensity and color – making it harder to reproduce multiple products.
Inconsistencies In Semiconductor Processing
It is a complicated and high-temperature process fabricating LEDs and involves growing layers of crystalline across a semiconductor wafer’s surface. The properties of a particular LED is determined by the quality of a layer. It is very hard to reproduce not just across one wafer, but to keep the same standard from wafer to wafer and even from day to day.
This means that while some LEDs that have been processed from a particular wafer will be usable in higher quality devices and applications than other LEDs taken from the same wafer. The lower quality ones are usually put to use in lower-end applications and products such as toys.
Lack of Standardization
One major downside of LEDs that still needs to be addressed is the distinct lack of standardization overall. There are a wide array of different standards that exist concerning LEDs in specific applications such as traffic signals and automotive lighting; but nothing that is set for LEDs across all industries and applications.
High Level Of Designability
However, with the constant improvements made to LED technology, a wide range of new design options have been made possible, that in the past were inconceivable.
Small LEDs – Huge Benefits
As LEDs can be incredibly small – for example, the average LED chip capable of a high level of brightness measures just 0.3 by 0.3 mm, while actual devices are only 1 by 1 mm; it has meant that they are flexible and versatile. There are various examples of market advancements being made thanks to the availability of LED devices that are ultra small and ultra bright.
One of the most common examples of this is with smartphone, that feature white, green and blue LEDs to backlight the LCD screens and keypads.
Low Voltage Lighting, But Needs Drivers
LEDs are sources of light that require very low voltages, but need a constant DC current or voltage to keep them running to an optimal level, which often requires drivers to be fitted. Because of this, an effective and efficient driver needs to designed and properly implemented to really benefit from all of the above advantages that LEDS have to offer.
Gap In Understanding Between the Lighting Community and LED Manufacturers
Of all the drawbacks mentioned above though, the most pertinent that really needs to be discussed and resolved is the gap in the understanding between the lighting community and the manufacturers who produce LEDs. Manufacturers are still not including the lighting community in their activities involving product developments and also do not provide the relevant information that can be used as a direct comparison to the information available from other light sources in competition.
On the other hand, the lighting community does not properly understand and appreciate as much as they should about LEDs and are not knowledgeable enough about thermal management and other vital issues. They also do not really understand why, as we noted earlier in this post, white LEDs do not perform is not very consistent at all.
Hopefully, we have helped to shed some light on some of the many benefits and drawbacks of LEDs, to better aid you in choosing whether they are the best lighting solution for your requirements.