LED vs HPS

PJ Diaz

Well-Known Member
LED dont put off much IR compared to 1000w HPS. With 1000w DE HPS if I put the back of my palm on my concrete floors in -10 °F winter outside in a basement the floor is warm. If I'm running LEDs the floor stays ice cold.. There is way less heat from LEDs to warm the room in the first place, then once the little heat provided by them fades the room drops in temps much more dramatically.

I don't care about the fancy numbers when I see plants do better under an LED I'll invest until then its all just gizmo gadget BRO ITS GOT 21000 UMOL PER SECOND BRAH 2.675 UMOL per second efficiency DUDE. Cool don't care. Prove its better and worth spending $1,400 on each fixture when you can spend $250 on a 1000w DE complete plug & play fixture that will easily yield 3 pounds per/light without question.
So I think you're saying that the radiant heat from your HPS lamp is absorbed by the concrete during the light hours, and then during the dark hours the heat is returned back the the plants and grow space by way of conduction and convection. That's reasonable enough, however the same thing could be accomplished with a low wattage heat mat. As far as total heat, assuming that the wattages are equal, LED and HPS fixtures should be the same temperature in an enclosed space. It's true that the area below an HID lamp will be proportionately much warmer than it would be below an LED fixture, but that's only because of how the heat is transferred differently between the two fixtures. Overall heat is the same, if wattage is equal.
 
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calvin.m16

Well-Known Member
So I think you're saying that the radiant heat from your HPS lamp is absorbed by the concrete during the light hours, and then during the dark hours the heat is returned back the the plants and grow space by way of conduction and convection. That's reasonable enough, however the same thing could be accomplished with a low wattage heat mat. As far as total heat, assuming that the wattages are equal, LED and HPS fixtures should be the same temperature in an enclosed space. It's true that the area below an HID lamp will be proportionately much warmer than it would be below an LED fixture, but that's only because of how the heat is transferred differently between the two fixtures. Overall heat is the same, if wattage is equal.
Radiant heat man..
 

calvin.m16

Well-Known Member
HPS produce more Radiant heat than a LED where LED have convection heat. This requires getting rooms hotter to achieve proper VPD and Leaf Surface Temps. LED are not worth the savings in power yet, if I switched all my 1000w DE HPS with LED I'd only be saving $1,000 on my power bill every year. Maybe if I was running 12+ lights I'd be more enticed.

Another silly thing is I see people running LEDs even without plants under them so they can keep their room temps up, where's the power savings in that?
Winter climate grows are going to need heat pumps or furnaces running to keep temps in acceptable range. With my HPS setup I can turn my 3 ton mini split off all winter and just use the lights to keep temps up.

Initial investment into LED is $12,000-15,000 for a 8-12 light grow.. HPS would be $2,500-3,500..
 
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Apalchen

Well-Known Member
I've experimented with LED supplementation it seems like the plants do best under consistent lighting spectrum and source. I've had some strains that take a lot of adjustment time between T5, LED, HPS etc. I feel like it would just stress them out or throw them off but you never know it could be killer if done right..
I know a guy with several large rooms (72 plants -plant per 4x4) and he runs the gavita 1700, hps, and cmh. He has rooms with all gavita 1700 as well. He still claiming the best bud is from mixed spectrum and it’s been several years since I’ve even been in one of his rooms but from his pictures I see he is stil running same set up.

I have a couple de hps in the front of my led room with no issue either.

Back when I ran tents I regularly ran hps and cmh together and that’s still one of the best combos for quality in my experience.

I do know what you mean about switching lights being stressful, but imo it’s more from par differences between the fixtures. After getting a par meter I realize my veg is under lit so the stress they show going into the other rooms is because the DLI changed so much. If I dim the flower rooms real low at first plants are fine. I need to get my veg up to 500-600 ppfd at 18 hours to be able to transition more smoothly into powerful light.
 

calvin.m16

Well-Known Member
I know a guy with several large rooms (72 plants -plant per 4x4) and he runs the gavita 1700, hps, and cmh. He has rooms with all gavita 1700 as well. He still claiming the best bud is from mixed spectrum and it’s been several years since I’ve even been in one of his rooms but from his pictures I see he is stil running same set up.

I have a couple de hps in the front of my led room with no issue either.

Back when I ran tents I regularly ran hps and cmh together and that’s still one of the best combos for quality in my experience.

I do know what you mean about switching lights being stressful, but imo it’s more from par differences between the fixtures. After getting a par meter I realize my veg is under lit so the stress they show going into the other rooms is because the DLI changed so much. If I dim the flower rooms real low at first plants are fine. I need to get my veg up to 500-600 ppfd at 18 hours to be able to transition more smoothly into powerful light.
I've done mixed spectrum even on clones I've had T5 center with LUXX Clone LEDs on each side, the plants didn't respond well. I'm a one or the other type individual I like to keep things as simple and predictable as possible. lol what do you plan to sell those 1930e for I might want 4 of them. :lol: :-D:bigjoint:
 

Kassiopeija

Well-Known Member
Somehow DLI is a flawed concept as it's based on PPFD - just a snapshot of the field-strength of light at a set point in your lamps light-cone.
But if your quantum-meter measures e.g. 1200ppfd at your canopy tops, how much would it measure 30cm below, or 60cm below (that point) if the plants were removed for that measurement.
--> that is going to give you different values depending on the inherent beam angle of the fixture, and mostly also be dependant on the actual power used in conjunction with the lamps distance.
A lamp cranks out a specific amount of light particles per second, and in a closed environment, most of these will hit the leaves and the total number of available photons is much more decisive than the light's field-strength at an arbitrary point taken.

Closer proximity calls mostly for wattage reduction which will also reduce the lights deep effect.
However, DLI doesnt take that into account.

PPFD is not PPF.
It's most obvious when, using HID, various forms/types if reflectors will change the PPFD measurements although the raw light-output is exactly the same. Because the reflector may change the ratio of direct light vs ambient/diffuse light... more so even the angle-of-incident changes how strong a light-sensor does detect.

These are, apart from spectrum & leaf temps, other factors at large to consider that even the LED direct-HPS replacement fixtures throw light somewhat differently
 
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PJ Diaz

Well-Known Member
Radiant heat man..
Isn't that what I just pointed out? The thing is, the overall heat is still the same, it's only directed differently. You can't get more or less than 3.41 btu's out of 1watt of energy, that is a fact of physics.
HPS produce more Radiant heat than a LED where LED have convection heat. This requires getting rooms hotter to achieve proper VPD and Leaf Surface Temps. LED are not worth the savings in power yet, if I switched all my 1000w DE HPS with LED I'd only be saving $1,000 on my power bill every year. Maybe if I was running 12+ lights I'd be more enticed.

Another silly thing is I see people running LEDs even without plants under them so they can keep their room temps up, where's the power savings in that?
Winter climate grows are going to need heat pumps or furnaces running to keep temps in acceptable range. With my HPS setup I can turn my 3 ton mini split off all winter and just use the lights to keep temps up.

Initial investment into LED is $12,000-15,000 for a 8-12 light grow.. HPS would be $2,500-3,500..
I'm not opposed to HID for additional radiant heat to increase leaf surface temp if needed, in fact I do that myself during the cold months. I add a 315 CMH between my LEDs, and frankly the plants turn out really great under that mixed spectrum. In the warmer months I'm fighting heat the other direction, so the lack of radiant heat from the LEDs works in my favor. I think most people prefer LED for the 25% power reduction to get the same amount of light, and/or for heat management. Plus LED boards last a lot longer than HPS lamps, so you forgot to figure lamp costs over time, and power difference costs in your calculations.
 

calvin.m16

Well-Known Member
Isn't that what I just pointed out? The thing is, the overall heat is still the same, it's only directed differently. You can't get more or less than 3.41 btu's out of 1watt of energy, that is a fact of physics.

I'm not opposed to HID for additional radiant heat to increase leaf surface temp if needed, in fact I do that myself during the cold months. I add a 315 CMH between my LEDs, and frankly the plants turn out really great under that mixed spectrum. In the warmer months I'm fighting heat the other direction, so the lack of radiant heat from the LEDs works in my favor. I think most people prefer LED for the 25% power reduction to get the same amount of light, and/or for heat management. Plus LED boards last a lot longer than HPS lamps, so you forgot to figure lamp costs over time, and power difference costs in your calculations.

HID are definitely more maintenance in the long run as well. I understand with many of the LEDs you're also buying into a 5 year warranty which isn't going to be cheap

I want the Gavita 1930e fixtures I can get them for $1,000 out the door at a nearby shop.. I just don't want to drop $4,000 right now on a row to "try". After looking up pics though I think the 1930e would actually compare to the 1000w DE HPS..
 

PJ Diaz

Well-Known Member
HID are definitely more maintenance in the long run as well. I understand with many of the LEDs you're also buying into a 5 year warranty which isn't going to be cheap

I want the Gavita 1930e fixtures I can get them for $1,000 out the door at a nearby shop.. I just don't want to drop $4,000 right now on a row to "try". After looking up pics though I think the 1930e would actually compare to the 1000w DE HPS..
I wouldn't buy anything Gavita, for multiple reasons. Number one, fuck that company who's in bed with Scotts and Monsanto. Number two, their fixtures are overpriced. Fuck Gavita.

A big part of the warranty is the driver warranty (7-years on the Meanwell drivers I have), which is covered by the driver manufacturer. It's not a big cost increase.
 

calvin.m16

Well-Known Member
@PJ Diaz Where I live we also have to account Distribution charges, basically per/kwh you use they charge you $0.045/kwh so that adds up too..

In reality bulbs cost me $800 every 14 months for 8 fixtures, distribution charges are higher due to higher watt consumption overall.

If I were to switch to the 1930e from the 1000 DE HPS I'd be saving around $2,000 per/year and removing lamp swaps from my to do list..

If I do make the change I will try to do a true side by side and I'll do 4 lights then if it works out good I'll switch all 8..
 

calvin.m16

Well-Known Member
I wouldn't buy anything Gavita, for multiple reasons. Number one, fuck that company who's in bed with Scotts and Monsanto. Number two, their fixtures are overpriced. Fuck Gavita.

A big part of the warranty is the driver warranty (7-years on the Meanwell drivers I have), which is covered by the driver manufacturer. It's not a big cost increase.
What would be a good alternative to the 1930e for bloom only? I've ran and own the Growers Choice 720e fixtures and they did not perform well in bloom.. I went from 2.5-3 #s a light to 1.5-1.8 #s a light about.. I ran higher temps to account for VPD and Leaf temps etc.. Didn't matter.
 

PJ Diaz

Well-Known Member
What would be a good alternative to the 1930e for bloom only? I've ran and own the Growers Choice 720e fixtures and they did not perform well in bloom.. I went from 2.5-3 #s a light to 1.5-1.8 #s a light about.. I ran higher temps to account for VPD and Leaf temps etc.. Didn't matter.
The only advantage to the Gavita 1930e is that it uses high-power diodes (as opposed to the mid-powered lm301 diodes which are standard in most fixtures), and you can hang them higher, so I guess it really depends on what your needs are. The only other fixtures that I know of (I'm sure there are others I don't know of) are the HLG QB96 Elite V2 boards. I one 6 of them myself, but I run them way underpowered for better efficiency. Four QB96's will run you just shy of $300, and two 480w meanwell drivers (dim them down to 400w each) to power them are around $300, so for $600 plus the cost of wire to connect them you can have something equal to the light output of a Gavita 1930e. 7-year warranty on those drivers too.

 

xtsho

Well-Known Member
The LED argument vs HID is a pretty pointless argument. Both can be used to grow good weed. I can guarantee that I can grow better weed with a $150 HID than many using some $700 LED. Lighting is just one aspect to growing. I've seen dozens of grows online where someone spent thousands and ends up with crap. I've seen and experienced spending a few hundred on a light and a tent and growing fire.

I could care less about PAR and PPFD numbers. I just put my plants under an HID and grow. I still use a T5 and will continue to do so. I also just bought another 2 pack of Vivosun 600 watt bulbs so I'll be sticking with the HPS in flower for more grows.

I urge any HID users catching flack from the LED users attempting to ridicule them for using HID to tell them to kiss



:mrgreen:
 

Apalchen

Well-Known Member
@PJ Diaz Where I live we also have to account Distribution charges, basically per/kwh you use they charge you $0.045/kwh so that adds up too..

In reality bulbs cost me $800 every 14 months for 8 fixtures, distribution charges are higher due to higher watt consumption overall.

If I were to switch to the 1930e from the 1000 DE HPS I'd be saving around $2,000 per/year and removing lamp swaps from my to do list..

If I do make the change I will try to do a true side by side and I'll do 4 lights then if it works out good I'll switch all 8..
They are a bad ass fixture, as far as the coverage and overall power of the light. I was super worried about hot spots vs bar fixture lights. But let me say they spread light the most even I’ve seen on par meter.
I don’t know how that lens does it but it’s very even coverage.

That being said someone could GIVE me enough fixtures for my other room and I wouldn’t hang them right now. Hopefully in a few months I’m back in here claiming I was wrong. I have been dealing with other issues.

I got a veg filled up now, just waiting to get the last of plants trimmed and out of the room now. All new healthy genetics but a very mixed run so we shall see how it goes.

I do have room to add another light, I’m thinking of adding another de to the one front corner of room and move my co2 tank over. Thing is will be yet another spectrum cause they have the ceramic hps bulbs in them atm.

I’m pretty sure the only thing I have to do to add one is move some stuff over. And at least I’ll have 3 lights in there I know will perform, and I can spread out plants a little more.
 

PJ Diaz

Well-Known Member
The LED argument vs HID is a pretty pointless argument. Both can be used to grow good weed. I can guarantee that I can grow better weed with a $150 HID than many using some $700 LED. Lighting is just one aspect to growing. I've seen dozens of grows online where someone spent thousands and ends up with crap. I've seen and experienced spending a few hundred on a light and a tent and growing fire.

I could care less about PAR and PPFD numbers. I just put my plants under an HID and grow. I still use a T5 and will continue to do so. I also just bought another 2 pack of Vivosun 600 watt bulbs so I'll be sticking with the HPS in flower for more grows.

I urge any HID users catching flack from the LED users attempting to ridicule them for using HID to tell them to kiss



:mrgreen:
I don't disagree with any of that, but of course the sword swings both ways.
An interesting twist, what if instead of investing into LED fixtures you were to invest in grid-tie solar panels? lmao for 10 grand I can setup a pretty beefy solar panel system to offset expense of higher wattage.. lol
$10K? You sure? I think it's usually around double that, but maybe depends on where you're at. I have an off-grid solar panel I use for ventilation of my lung room, and clone lights. Cost around $500 the the 200w panel, charge controller, and two 12v marine batteries. I know I'm not making my money back on the investment, but I like to tinker, and like the fact that I have a bit of backup power when the apocalypses come.
 
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