How Cold Weather Affects LED Lights

You may not believe it. You may not notice it. You may not even be aware of it.

But, in December and January, your LED lights will be performing marginally better. Winter months and cold weather improve the intensity and lifespan of LED lights. Actually, it’s more accurate to say that ambient temperature, and therefore the temperature at the source of the light, will improve LED light performance, not just cold weather. 

“In general, the cooler the environment, the higher an LED’s light output will be. Higher temperatures generally reduce light output,” according to the National Lighting Product Information Program in the Lighting Research Center at the Rensselaer Polytechnic Institute. 

“Prolonged heat can significantly shorten the useful life of many LED systems. Higher ambient temperature leads to higher junction temperatures, which can increase the degradation rate of the LED junction element, possibly causing the light output of an LED to irreversibly decrease over the long term at a faster rate than at lower temperatures. Controlling the temperature of an LED is, therefore, one of the most important aspects of optimum performance of LED systems.”

How Do Incandescent Bulbs Compare To LED Lights?

In contrast, incandescent bulbs do not function well in cold weather. 

Why?

It’s because of how they’re built. An incandescent light bulb takes energy and heats a tungsten filament until it glows. In a colder environment, it takes longer to heat up and once heated generates too much heat for the cold environment. 

An LED light in cold temperature will start instantly while other sources of light could take anywhere from a few seconds to up to 60 seconds. 

An LED light’s junction temperature at 25 degrees Celsius or 77 degrees Fahrenheit performs optimally at 100 percent relative light output, but increases to almost 120 percent relative light output, according to the National Lighting Product Information Program.

“Junction temperature is the LED’s active region; the point at which the diode connects to the base. This is where the electrons jump between the two semiconductors to produce [a] photon,” according to Philips. “A low junction temperature helps LEDs to produce more light [and] also reduces lumen depreciation. Junction temperature is affected by the driver current, the thermal path, and the ambient temperature.”

Lumen depreciation, by the way, is the reduction in light brightness over time, or how much the light dims. What is a lumen? In short, it is the relative brightness or output from the source of light. It’s not to be confused with watts, which is a measurement of the energy needed per second to power the light. Nor should it be misconstrued as lux, which is related to the amount of light on a subject from a source.

So, LED Lights Are Better For Colder Temperatures

The implications of LED performance in cold weather temperatures are important to consider in residential, business, and recreational environments. Given their extended lifespans and improved efficiencies in output, LED lighting systems are an effective use of time, energy, and resources. 

Less energy is being used than their counterparts and in cold-weather areas more output is generated by LED lights.

This is confirmed in scientific literature, of course.

“The study of temperature dependence of various parameters in light emitting diodes (LED) has importance from both the viewpoints of basic physics as well as different technological applications, particularly in low temperature regions. The performance of an LED is significantly dependent on temperature,” according to a study published in the Journal of Semiconductors. 

“The light intensity varies with the driving of the LED current as well as its environmental temperature and it is known that with the lowering of temperature, intensity increases and carrier lifetime decreases.”

Carrier lifetime does not refer to the durability or resilience of the housing of the LED light. Carrier lifetime, rather, refers to the energy transfer at the junction of an LED light. 

The bottom line is this:

In cold weather, LED lights are going to outperform many other types of lights when it comes to intensity, lifespan, and functionality.