carbon trust green business fund 1 - How long do LED lights last?

The question “How long do LED lights last?” is one we are asked every day

LED lights can save you a considerable amount of money each year. But, how long do LED lights last?

There’s no point in investing in LED lights if they are likely to fail after a short time.

Fortunately, LED lighting is very robust and lasts for a long time.

LED Lights – Predicted Lifetime

All LED lights have a predicted life-time stated in hours on their data-sheet.

50,000 hours is quite typical for high quality, commercial and office LED lighting.

You may find individual LED bulbs with a lifetime as low as 6,000 hours.

LED lifespan
LED Warehouse

How long LED Lights last – An Example

To make these numbers meaningful, you need to work out how long your lights are on per year.

For example, let’s imagine a warehouse with racking which opens at 08:00 and closes at 17:00 each day. The warehouse is operational 5 days a week, and 50 weeks per year. That equates to 2,250 hours per year.

If you install LED lighting to illuminate the aisles between the racking and the LED lights have a life-time of 50,000 hours each, then each light is predicted to last 22.2 years. This number is reached by dividing 50,000 by 2,250.

If, on the other hand, the warehouse was operational 24 hours a day (instead of 8 hours), the LED lights would be on 6,000 hours a year. This would bring the predicted life-span of the LEDs down to 8.3 years (50,000 divided by 6,000).

Warehouse highbay LED lighting

LED Drivers and Chips

There are two main components to an LED light: the driver and the chips. The chips are what actually emit the light. They are responsible for how bright the light is (see our page on lumen output). The driver, on the other hand, provides the chips with power.

When asking the question “How long do LED lights last?”, you need to specify which part of the LED light.

For example, LED chips in well-manufactured lights are very unlikely to fail. When supplied with electricity, they give out light. It’s a simple process.

The driver that powers the LED chips is a more complex piece of equipment. It’s doing more work than the chips and is therefore more likely to fail.

If an LED light suddenly stops working, the problem is almost certainly with the driver, not the chips.

Fortunately, drivers are often separate to the main LED light. If a driver fails and is under warranty, the manufacturer will send a replacement driver for free.

LED Light Degradation

A high quality LED light will last a very long time. Up to 50,000 hours as we have seen above.

However, the amount of light emitted on the day of installation will be less than the amount of light emitted in the future.

This is due to degradation. Over time, the LED chip degrades and is no longer able to give out the same amount of lumens as when new.

You can find out how quickly an LED light will degrade from the data-sheet. You might see, for example, an ‘L70’ rating at 50,000 hours. This means that after 50,000 hours of use, the LED light will give out 70% of the original promised amount of light.

Let’s say a light’s output is 10,000 lumens when installed. If the light is L70 at 50,000 hours, then after 50,000 hours it will only give out 7,000 lumens (50,000 times 70%).