As LED lighting awareness grows and adoption of the technology in grow facilities continues to increase, the knowledge base and standards of LED grow lights remain a mystery. This is due to the fact that there are currently no standards set for horticultural lighting. This is something that is being addressed and will most definitely play a part in helping customers choose the right product in the future. Hopefully we can shed some light (pun intended) on the subject for you.
Most people when they think of LED’s think of long lifespan, efficiency and a technology that has the potential to change the future of lighting as we know it today. Many LED grow light companies promise a 2, 3 even 5 year warranty on parts such as fans or drivers. Depending on how the manufacturer built the light you may have other parts that need replacing which invariably will fail before your light output does. But what about the output of light and how it affects the plants? LED chips and designs require well thought out solutions to dissipate heat and a good fundamental structure. Overlook these important facts and the light output of an LED product diminishes quickly. High pressure sodium bulbs offer similar life expectancies on light output and also have different price points. For example, a low end high pressure sodium bulb (HPS) with 5,000 Hrs of life could cost R400 and a high end HPS with a 12,000 Hr life time could cost you anywhere from R1200 and up.
When LED lights were first introduced they quickly became popular and in some countries power companies even offered government grant monies to end users who reduced their carbon footprint and energy consumption by installing LEDs. Choosing a LED light can be confusing to the average customer and as the LED industry expanded, people quickly learned that not all products are made the same. This was due to the vast amount of “lower” end quality bulbs making it to the market while only few products maintained high quality standards. In order to keep tax payers' money from being rewarded toward lower end LED products that don’t provide the true benefits of the technology, the US Department of Energy set standards, that if passed, guarantee the true potential of LED technology. Those standards are called LM79 and LM80.
LM or Lumen Maintenance 79 is an approved method for taking Electrical and Photometric measurements of Solid-State Lighting products. It covers total flux (light output), electrical power, efficacy, chromaticity, and intensity distribution and includes parameters such as:
LM-80 refers to a method for measuring the lumen depreciation and junction temperatures of solid-state lighting sources, such as LED packages, modules and arrays. This is to establish a curve of the diminishing wear on the LED or an LED’s life time. LED chip manufacturers are required to delay product release to the market for a year. This is done to truly test the LED and make sure it does what the factories say it will. These tests must be done by third party labs that are certified by the US Department of Energy.
A batch of LEDs (usually 50+) is tested at the junction point of the LED at three different temperatures, usually 55, 85 and 105 Degrees Celsius. The lumen output is recorded every hour for 6,000 to 8,000 hours (almost a year) and a base line curve is made. With this data, a detailed performance chart can be produced showing actual LED lumens and usable light over time. You can now determine the degradation curve and know the lumens and lifespan of a specific lighting fixture. If this test data is available, one way to verify it is to compare the LM-80 data for an LED grow light fixture against the LED chip manufacturers data by matching the temperature of the LED inside the fixture to the manufacturer’s spec. This will tell you how much degradation your LED grow light has taken over time.
Spectrum King LED is proud to say that all their LED grow lights are certified and tested by multiple third party laboratories with a light diminishing factor of about 1.4% per year on normal use. Grow operations using 12-12 time cycles can expect 6.5 years before losing even 10% of light (90% original light remaining) and over 15 years to reach 70%. True quality.
SPECTRUM KING LED DATA: