Do LEDs age and get dimmer over time?

[hypnogogia]

As the title says, do LEDs age and lose intensity over time? If so, at what point should they be replaced?

 

[Jorge O'Reilly]

I think they do. It would depend on the specific LED. I have really crappy LED strips that cost about 2$ a strip and I change them every year or so. I suppose a good quality light with Cree LEDs or similar would last for years, given adequate cooling

 

[zozo]

As long as the current doesn't change the LED will stay burning at its initial intensity... But connections can corrode and this can cause resistance that alters the current flow, less current flow through and or lower voltage can cause an LED to dim. For the rest LED burns or it doesn't, in general, is 50.000 hours advertised, but depending on the quality this can vary significantly. In most cases, it's the required constant current driver or sensing resistor the first one to burn out before the LED is at its end of life. That's the downside, the LED might do the 50.000 but the other components' lifespan is not mentioned in the sales pitch.

It's tough to say when what is... I have an LED strip above the kitchen counter that still burns 24/7 already for years and each single LED is still burning ok. I had some strips ordered from the same batch burning out years ago...

Above an aquarium with relatively high air humidity corrosion can kick in rather quickly... Even IP68 still can have minor cracks and start to corrode...

 

[oreo57]

As the title says, do LEDs age and lose intensity over time? If so, at what point should they be replaced?

The simple answer ..yes
As to replacement you get into the not so simple area.

What do L/B values L90/B10, L80/B10, L70/B50 actually stand for? – Caribou

caribou.com.au

The L80/B10 specification with 60,000 hours means the luminous flux of no more than 10% of all LEDs reduces to less than 80% of the initial lumens within these 60,000 hours. L70/B50 90,000 hours means 50% of the LEDs have at least 70% lumen maintenance for the projected 90,000 operating hours.

There is more likely other parts that will fail long before the LEDs are useless.
Just a matter of keeping them cool-ish.
Like with household bulbs and all the circuitry near the major heat source.

Sooo say you run at 80% giving you room to " make up" for the led losses over say 5 years you could potentially use them for say another 5 years.
After those 10 years if the circuitry is still good ( you will probably had replaced the power supply at least once) they may still be functional for more years at a reduced ( below your 80% which is now 100%) output.
At which point you no longer have an aquarium anyways. 😁.
Soo you have a lamp life vs an led life

 

[simon_the_plant_nerd]

As LED luminaires rarely have user replaceable components, the lifespan of the entire luminaire is considered rather than the lifespan of the individual components. Modern LEDs will typically outlast the drivers by some margin.

If you construct your own unit you may over specify the driver which could then outlast the diodes. However, in a commercial product, this is incredibly rare.

 

[The grumpy one]

Yes they do. The standard term lifetime refers to how many hours they will last until the light output drops by 30%.
One of the leading factors is the temp that the unit operates at. The hotter the LED the shorter the life.

So the cooler you can keep them the longer they will last. Well ventilated is the way to go. Do not seal them in a box. Ahh that is exactly what we do for aquarium lighting as we don't want the moisture to get in. Hence the heat fins you see on the aquarium ones. Bit of a compromise between failure due to moisture and failure due to heat.

 

[oreo57]

Well this has very little to do with this topic except for how he judges longevity.
More just for interest and the fact he tested waveform bulbs.

 

[jaisol]

Yes they do dim over time, more annoying some start to flicker, either individual LEDs or more commonly the whole light (usually the power supply). I see a lot of various LED lights and life spans vary from 18 months upwards for the same identical lights. The theory behind them is good, however build quality and heat dissipation tend not to be so good, ... profit margin V quality.