5 Reasons NOT to use LED

Many manufacturers are using their LM90 data for chips on spec sheets, not actual fixture life so 50K hours may not actually be true. And when you drop below 90 percent output, there is no lamp to change, but the whole fixture.

Obsolescence -
Remember LEDs from 4 years ago? Blurple and SUPER Expensive. Think about what will be here in 4 years. Do you want to be left holding the bag?

No UV-
Light in the UV range is proving to be valuable in THC production. The best strains in the world evolved in geographies that have the highest amount of UV. UV LEDs are self destructive and will shorten the life of the fixture if used in an array.

Fixture Weight and Fans-
LED Fixtures can be heavy because of the the amount of Aluminum it takes to cool the chips. If fans are used to reduce weight, they become a common mode of failure.

The up front costs for fixtures are still 3 to 5x what a proven HPS is. Even with rebates, the expense is still very high to gamble on an investment.


What is your opinion of using LED’s from a sustainability point of view?


Do you have any data regarding reduction in light output with led?



This is total clickbait. I am an advocate of sustainable crop production. As long as we take into account the impact of manufacturing compared to older sources (Life Cycle Analysis), LED is 100 percent the future of horticultural lighting. There are many reasons but I am focusing mostly on the metrics of CO2 and Mercury reduction.


You got me, you dirty dawg ;). Keep up the good work :smiley:


@JoeGrow there are many resources on light output reduction. You can look at LM Data (Lumen Maintenance) on any chip spec sheet:

L70 is how they spec LED for visual because 70 percent is ok for humans. Plants need an LM90 of 50K or better to be commercially viable.

Another consideration is color shift since “white” LEDs are just Blue LED’s with a phosphor coating and have a tendency to revert, drifting back to the blue origin. Quality of light i.e. Red to Blue Ratios has a direct plant response.

Check out work by Ron Tuttle from CREE on the topic


My last post tanked so I went with “hot chicks and free herb” clickbait style. Holler with any LED needs :wink:



Thanks for your post! I just want to contribute my experience as well:


You are true about your claims about most of LED manufactures. A reasonable approach is to calculate with L90 @ 25,000h if the system has been designed properly! Unfortunatly, same is true regarding the claims about efficiency! :wink:

By the way your OSRAM spec sheet only says: “Lumen maintenance: Test results according to IESNA LM-80 available” That’s the problem with most of the LED manufacturers, a few years ago they used to publish graphs but nowadays they don’t…


The break even of LED tech has taken place in 2017/18! Everything before should not be taken into account… Again the system design will make the difference. LEDs are not the problem normally LED drivers and power supply units are the biggest issue…


UV is important but Blue light will do as well! see Valoya

Weight and Fans

You should have said “Weight vs. Fans” since only fans will allow a manufacturer to reduce weight significantly :wink:


Total cost of ownership is what matters most. Depending on your electricity rate the best LEDs are already outperforming HPS regarding TCO… For example if you calculate TCO for 25,000h in California (average electricity rate 0.14 USD/kWh) you will save about 400 USD with a FLUENCE SPYDR 2i compared to a GAVITA Pro 1000e DE…

But in the end the revenue per fixture has to be taken into account as well… And that’s the hard part of the game…

I don’t get your point here:

  1. L90 at the end of 50,000h (= 11.4 years of flowering) is impossible in a real world set-up! We have developed our first LED grow light in 2008 and also analysed most of the LEDs out there…

  2. In the end, plants do need energy: µmol/s or better mol/day, they don’t care about the efficiency of the light source… The quality of the light is also very important and will highly affect the effectivity of a light source… That’s much more important if cultivators focus on yields and quality… since electricity is quite cheap in the US :wink:




:joy: Great stuff here, just adding some additional thoughts on this issue;

Durability & Fans
Totally agree that most manufacturers of LED lights drastically misrepresent the working lifespan of their fixtures. While heat is the main culprit decreasing fixture lifespan, fans are a source of electrical failure and a bulky addition to the fixture weight. That’s why we don’t use them. Our fixtures are lightweight, but not flimsy, and the heat is dissipated by the aluminum heat sink in the housing.

Definitely avoid cheap LED lights, as they are designed to last only as long as the circuit boards or diodes. Our latest fixtures actually have a modular design so you can swap out the circuit board (to try different spectrums, for instance) without replacing the whole fixture – and in some cases, without even taking it down from the mounting.

Our 10 year warranty is our way of staving off that obsolescence. :slight_smile:



Thanks for the reply!

You have to start digging with a rep to get to see the real LM Data! I just google a random Osram Oslon sheet but you are right, they no longer publish graphs, especially for Life Time Analysis.

I agree that 17/18 has been the tipping point. 5 years at this pursuit and I am just now confident in the performance of LED. My concern now is diverting the waste stream of each innovation cycle. I am confident that the current form factors will hold for a while and repurposing or recycling the waste from each generation is our new “bulb in the trash”.

It seems to me that the chipset technology is the slower of the two. Drivers (meanwell 96%) have been at 90 percent plus efficient. Size is the biggest issue for drivers imo.

Man, I have hemmed and hawwed about Fans. I know there are some out there that work for the duration, but I have not spec’d them in a build or commercial application. I have some friends over at FOHSE who want to make a believer out of me.

Total cost of ownership and Life Cycle Analysis (sustainability point of view) have to be considered. I’m looking at the long haul.

“Plants need LM90”- poor wording there. 50K hours for 90 percent output is just not true in my experience either with mid-power plastic based chips especially. Ceramic chips and good junction temps MAYBE, but there is a lot of active marketing going on in this space.

As we approach 3.0 mmol/J, the cost to produce a pound will start the decline of HID. If you need UV on your strains to peak out numbers, use a greenhouse or grow in a hybrid lighting setup.


@SpecGradeLED I am all about Modular Design, some manufacturer’s are making the “bars” inter-changeable so you can just swap them and leave the driver/chassis in place.

I sell the industry leaders because of lead times, volumes, warranty etc. 10 year warranty is bold friend. Send along some info about your fixtures. My job is to constantly evaluate the latest and greatest, and our product card is ever changing.


Thanks @BG_SAGE, I’ll DM you some info!


Agreed I’ve heard opposite story from many LED converts, higher yield and THC!


@nateboucher1980 the best runs I’ve ever done are under LED! It takes a little getting used to. Definitely the first time I’ve ever had to run a heater in a garden.

What is your experience?


Your Verta-8 is the nicest light I have ever owned, the quality of it is incredible; the first time I unpacked it I thought; “Wow, this must be what a light would look like if AMG designed it.”

As for HID over LED? I literally gave away all of my old HID lamps and I will never go back to using those dinosaurs. I have a 7000 square-foot facility, and watched my power bill drop from $6,800.- a month, to about $2,200.- a month. I was finally able to humidify appropriately to achieve constant VPD and my plants love the reduction in overall heat. Since getting rid of HID lamps, I have eliminated powdery mildew in my entire facility.

I’ve also seen higher terpene expressions, and overall happier plants.



Sounds great Todd!

From a TCO perspective, can you tell us the break-even point considering the initial cost of the LED vs HID as well as the cost of any heating equipment and related power costs?

Also, at what temperature are you running? NoCal or Socal?



That is awesome to hear. I just had and excellent call with Rick @SpecGradeLED and I am impressed with the intention that have put in to heat management and build quality. We will be evaluating some of their lights in our Denver facility soon.

HID and the Infrared light cause humidity spikes even if you have your environment pretty dialed. Leading to PM and other problems being tough to manage.

If you know anyone else converting to LED, I facilitate proper disposal of HID lamps to keep the Mercury out of the landfill.



Infrared is important for plant development, no? Dealing with humidity is easily handled with quick drain rockwool cubes watered once a day when the lights come on. While I don’t have data on the issue with led I would expect that micro-dosing, which is gaining popularity, would still have issues with humidity.

Is anybody seeing a reduction in dehumidifcation requirements with led and multiple feeding cycles per day?


I’ve had the same facility for over nine years and I do not bother to do cost analysis. It would be impossible to do considering I have been raided by the DEA and had them pretty much rob me of over 40 HID lights, and destroy a couple years worth of work back in 2012, and then, because I would not cooperate, they prosecuted me from 2013 till 2017.

I also don’t sell cannabis flowers, so it’s really hard to put a price projection on the genetics I am collecting and the value of the seeds I am making.

I keep my flower rooms at about 72°, and I keep my mother rooms slightly warmer at about 74 - 76°.


Thanks Todd, appreciate where you are coming from. Surely somebody has an answer. Every cultivation investor I’ve ever met requires such info before writing a check. Besides, at a spot wholesale price of only $1,100/lb, that has got to matter to them!

Do you have to heat your facility? If so, what does that cost in equipment and utilities, if I may ask?