LED lifespan and degradation

With any new technology, there exists a learning curve and a series of stepwise improvements through the hard lessons learned. One of these hard lessons in LED lighting, which is not frequently discussed and has yet to be discovered by many growers, is LED degradation. Due to a competitive market, it’s not a topic most manufacturers like to touch as it may raise complex questions from prospective customers. This article will outline all the essential details you should know to make an educated choice on your next light purchase.

LED degradation is a term used to describe the gradual reduction in a fixture’s output over time due to wear and tear. When you purchase a product, the output specifications are listed, but these values are for when the product is new. It’s important to understand that this value may decrease slowly or rapidly depending on the quality of the product.

Causes of degradation
There are three main factors that determine the level of degradation in a fixture: the quality of the LEDs used, the thermal management of the chips, and the quality of the drivers. Additionally, how hard the LEDs are driven can also impact degradation. Understanding these factors can help you make more informed decisions when purchasing LED fixtures.

The design of a fixture always compromises between the above aspects and the price. Compared to older technologies such as HPS, more variables are at play in developing LED fixtures. This has led to a market with large price and quality differences. Where the price difference is obvious, the difference in quality is more difficult to spot and often obscured by marketing.

It is possible to produce cheap LED fixtures using inexpensive LEDs and simple mechanical design. By ‘overdriving’ LEDs, which means pushing them beyond their recommended operating conditions, the output can be decent. However, overdriving LEDs combined with poor thermal management can increase the wear and tear on the chips. This can lead to a faster degradation rate, especially when starting with inferior parts. We have seen poorly designed and manufactured fixtures in the market that degrade output by more than 10-15% annually.

Business and profit impact of light degradation
A 15% reduction in output directly translates into an equally smaller potential harvest. This decrease in productivity can significantly impact a facility’s turnover and profit, potentially leading to a rapid decline in profit. While cheap lighting may seem like a cost-effective solution initially, the decrease in production and turnover over time, coupled with unchanged energy consumption and expenses, can quickly erode any perceived savings from cheaper lighting.

The most important to grasp is that degradation is a snowball effect. When high-quality components are combined with good thermal management, degradation will be minimal. On the other hand, lower-quality LEDs degrade faster by themselves. When combined with poor thermal management and overdriving the chips for more attractive leaflet values, these design choices compound into massive output losses. This underscores the importance of investing in quality LED fixtures with good thermal management, providing a sense of reassurance.

How to judge a fixture on expected degradation
At DLI, we understand that LED degradation can be challenging to judge from a leaflet, which is all the more concerning. That’s why we provide a comprehensive warranty not only on the product itself but also on the output over time. This means that if your fixture’s output drops below a certain level within a specified period, we will replace or repair it. This warranty ensures that you, as a grower, can focus on your plants’ growth and not worry about the potential impact of LED degradation on your profitability. Essentially, you purchase light on your crop instead of just a product.

One aspect that may not be obvious but can significantly influence the lifespan of LED fixtures is cleaning. Over time, surfaces can build up dust and debris, which can reduce thermal transfer. This can cause fixtures to run at higher temperatures, increasing the degradation rate. Therefore, periodically cleaning your fixtures is vital to ensure good thermal management and maintain the clarity of lenses or coatings, which can help reduce degradation and extend the life of your fixtures.

Having outlined the essentials, it’s clear that considering the products’ entire life cycle and the impact of degradation is one of the most important factors when purchasing a lighting system for your facility. It’s also clear that the initial purchase price of a product doesn’t guarantee success in the end. An output guarantee will ensure happy plants, stable turnover, and increased profits over the lighting system’s entire lifespan.

Please get in touch with us for more information on the warranties and peace of mind we can offer to you and your facility.