The age old question HPS, MH vs LED

[TheSadVeryBadMadGrower]

1 watt is one watt. Theres no difference 600 watts of led will make the same heat as 600 watts of his or cmh

is it the draw at the wall watt that's being measured? just trying to learn....lets say a mars light draws 300 at the wall.....even though they call it mars 1000w led. that would be the same as a 1000hps ?

 

[Lordhooha]

is it the draw at the wall watt that's being measured? just trying to learn....lets say a mars light draws 300 at the wall.....even though they call it mars 1000w led. that would be the same as a 1000hps ?

That's l marketing junk and what gives led a bad name

 

[Lordhooha]

That simply means you have 300 watts of heat to deal with.

 

[LarsVegasNirvana]

is it the draw at the wall watt that's being measured? just trying to learn....lets say a mars light draws 300 at the wall.....even though they call it mars 1000w led. that would be the same as a 1000hps ?

It's watts at the wall. A mars light that draws 300w at the wall has the same heat output as a 300w HPS. Which is about a third as much heat as a 1000w, so no, not the same. The only difference is the light from the HPS heats up the first thing it touches, and the light from the LED bounces around for a little bit longer before it inevitably is absorbed instead of reflected.

 

[TheSadVeryBadMadGrower]

I was always under the assump

That simply means you have 300 watts of heat to deal with.

Yea I know its Marketing when its the actual draw from the wall being measured. I was just always under the impression that a HPS light will run much hotter then the LED unit. i have drivers outside of my 2x4 so the heat is easier to deal with then my 4x4 with the drivers inside.

 

[TheSadVeryBadMadGrower]

It's watts at the wall. A mars light that draws 300w at the wall has the same heat output as a 300w HPS. Which is about a third as much heat as a 1000w, so no, not the same. The only difference is the light from the HPS heats up the first thing it touches, and the light from the LED bounces around for a little bit longer before it inevitably is absorbed instead of reflected.

Thanks for breaking it down some. We learn something new every day.

 

[Lordhooha]

I was always under the assump

Yea I know its Marketing when its the actual draw from the wall being measured. I was just always under the impression that a HPS light will run much hotter then the LED unit. i have drivers outside of my 2x4 so the heat is easier to deal with then my 4x4 with the drivers inside.

Led runs no warmer nor cooler than if it's a watt for watt comparison.

 

[twalte]

Led runs no warmer nor cooler than if it's a watt for watt comparison.

I’m getting ready to convert from a 1000 watt HID to a 930 watt LED (at the wall). So this means that the LED will put off similar heat if run at full capacity?

 

[TheSadVeryBadMadGrower]

So my TSL-2000 has a draw I think of 300-315ish from the wall. Does a HPS of the same exact draw as the LED have a higher running cost? I should have paid attention a little in this department but I was too busy tryin to get laid and stoned lol.

 

[LarsVegasNirvana]

Thanks for breaking it down some. We learn something new every day.

The heat from an HPS comes mostly from the IR light it puts out, so you feel it's warm if you put your hand under it. An LED puts out most of it's heat through the heatsink on the back, so it feels cooler under it. But since both the front and back of the light are both in the tent, it heats it up the same, assuming it has the same watts at the wall.

Like I said before the important part to understand is that you have to run an HPS room cooler to maintain the same leaf surface temp. That means you have a lot more AC required to achieve an optimal environment than if you ran the same wattage of LED. So even if you run the same wattage you're still going to save money on your electric bill. You're also going to get TWICE as much light, so you're saving money and yielding more. And some people here are actually arguing that it's better not to do that. LOL!

 

[TheSadVeryBadMadGrower]

The heat from an HPS comes mostly from the IR light it puts out, so you feel it's warm if you put your hand under it. An LED puts out most of it's heat through the heatsink on the back, so it feels cooler under it. But since both the front and back of the light are both in the tent, it heats it up the same, assuming it has the same watts at the wall.

Like I said before the important part to understand is that you have to run an HPS room cooler to maintain the same leaf surface temp. That means you have a lot more AC required to achieve an optimal environment than if you ran the same wattage of LED. So even if you run the same wattage you're still going to save money on your electric bill. You're also going to get TWICE as much light, so you're saving money and yielding more. And some people here are actually arguing that it's better not to do that. LOL!

With my tents, I do an "iron lung" with my air going into my tents. I have air coming from outside into the room then into my tent. I think I'm going to have to give a small HPS light a try next go around. Like I said, Ive stayed away because I was always under the impression they give off massive amounts of heat.

 

[Lordhooha]

I’m getting ready to convert from a 1000 watt HID to a 930 watt LED (at the wall). So this means that the LED will put off similar heat if run at full capacity?

Pretty much the drivers just like the ballast run some heat. But if I put a 1000 or however many watts of led in my rooms itll heat up just as much as my cmh at the same wattage.

 

[xtsho]

You didn't answer my question. Why don't you downgrade to an even less efficient light? If it's such a good idea, why don't you do it? You're obviously just justifying what you're already doing.

Why do idiots with shitty lights have the most problems? Because idiots are the kind of people who buy shitty lights and idiots kill plants. You're really dumb.

I'm condescending towards people who CLAIM HPS IS BETTER, not people who just use it. Some people use it but understand that there is an upgrade available without having sour grapes about it.

Why make it? BECAUSE YOU HAVE NO FUCKING ANSWER FOR MY QUESTION AND THAT SHOWS HOW RETARDED YOU ARE TO EVERYONE READING THIS.

Yeah, I'm working for the LED mafia, and we're conspiring to point out to the world how retarded you are for using HPS. You caught me.

Calling other people dumb is a sign of your own insecurity. Using caps lock shows you to be a moron. Do you think the use of capitals validates the word salad you wrote? It's like you're having a bout of mental diarrhea.

If it wasn't for people like you I might go the entire day without having a good laugh. In a few years when and if you graduate from high school, grow up and mature some more maybe you'll realize just what a pathetic jerk you are. Or maybe not. I've found that people like you never change. You just double down and get stuck on being stupid. It's funny that you mention LED mafia because you sound just like another wannabe gang banger that was on here not too long ago talking shit just like you. You have become nothing but a source of amusement to me and I look forward to your next hilarious post. Please continue.

 

[Kassiopeija]

Light makes heat too. 100% of the electricity you put into a light will end up as heat. It doesn't matter how efficient the light is. A 1000w hps puts out the same heat as a 1000w LED.

The difference is you get twice as much weed per dollar of electric bill out of the LED.

It's watts at the wall. A mars light that draws 300w at the wall has the same heat output as a 300w HPS. Which is about a third as much heat as a 1000w, so no, not the same. The only difference is the light from the HPS heats up the first thing it touches, and the light from the LED bounces around for a little bit longer before it inevitably is absorbed instead of reflected.

yes, and because of the direction of LED light most of it is absorbed by the leaves. if the photon is absorbed by a chloroplast it'll trigger a chemical bonding, and only a small fraction - the rest of the energystate of what's left over, is subsequently converted to heat. Ofc there are other materials there which can absorb photons that range in the visible spectrum which then can cause higher excitation states of baryonic matter.

However, the energy (heat) is not gone just chemically conserved - it will be released again upon decomposing. That's the reason why stuff thats decomposing heats up and can be used to drive a power plant.

And because LED puts out more PAR than HPS the emitted photons will create relatively more biomatter than initial heat.

Also, one reason to go for LED is to draw less power from the wall, so it makes not much sense to even compare the same tent-power-intake....

 

[LarsVegasNirvana]

Calling other people dumb is a sign of your own insecurity. Using caps lock shows you to be a moron. Do you think the use of capitals validates the word salad you wrote? It's like you're having a bout of mental diarrhea.

If it wasn't for people like you I might go the entire day without having a good laugh. In a few years when and if you graduate from high school, grow up and mature some more maybe you'll realize just what a pathetic jerk you are. Or maybe not. I've found that people like you never change. You just double down and get stuck on being stupid. It's funny that you mention LED mafia because you sound just like another wannabe gang banger that was on here not too long ago talking shit just like you. You have become nothing but a source of amusement to me and I look forward to your next hilarious post. Please continue.

Calling me insecure doesn't change the fact that you're retarded. I could be Satan himself and you would still be an idiot. And idiot who can't answer my question. Do you have any idea how good the CRI is on incandescent bulbs? It's like, the best light you can get. So why don't you use it?

 

[LarsVegasNirvana]

yes, and because of the direction of LED light most of it is absorbed by the leaves. if the photon is absorbed by a chloroplast it'll trigger a chemical bonding, and only a small fraction - the rest of the energystate of what's left over, is subsequently converted to heat. Ofc there are other materials there which can absorb photons that range in the visible spectrum which then can cause higher excitation states of baryonic matter.

However, the energy (heat) is not gone just chemically conserved - it will be released again upon decomposing. That's the reason why stuff thats decomposing heats up and can be used to drive a power plant.

And because LED puts out more PAR than HPS the emitted photons will create relatively more biomatter than initial heat.

Also, one reason to go for LED is to draw less power from the wall, so it makes not much sense to even compare the same tent-power-intake....

Yeah I didn't mention that, or the latent heat of evaporation.

 

[LarsVegasNirvana]

With my tents, I do an "iron lung" with my air going into my tents. I have air coming from outside into the room then into my tent. I think I'm going to have to give a small HPS light a try next go around. Like I said, Ive stayed away because I was always under the impression they give off massive amounts of heat.

You have to run the room cooler though, so it's the same heat but it's harder to deal with because you need to cool the room more. Basically if your tent runs at 82F with an LED you're set because that's the optimal air temp for LED. But if you have the same wattage of HPS in there and you're at the same 82F you're like 5-7F too high so you need to vent a lot more or run AC more or whatever. If you have that kind of heat budget available already then it won't matter, but if you're paying for air conditioning and you have to crank it down to make that happen then it's definitely going to feel as if it's making more heat.

People have done side-by-side grows in the same tent with LED and HPS and they usualy run it at the ideal LED temp to show you how shitty HPS is. So if you do this, whatever plant is getting all the IR light from the HPS is going to have up to 10F higher leaf surface temp than the plants that aren't lit by the HPS even though they're all in the same air temp. That plant with higher-than-optimal LST is going to suck compared to the ones next to it.

I like running lights that put out IR on an inkbird temp controller so that they warm up the room a little but don't overheat the leaves all the time. Any time my tent gets too cold my magnetic induction lamp kicks on until it comes back up to temp. I could just use a heating pad or space heater instead, but at least this way I'm also producing some extra light at the same time.

 

[TheSadVeryBadMadGrower]

You have to run the room cooler though, so it's the same heat but it's harder to deal with because you need to cool the room more. Basically if your tent runs at 82F with an LED you're set because that's the optimal air temp for LED. But if you have the same wattage of HPS in there and you're at the same 82F you're like 5-7F too high so you need to vent a lot more or run AC more or whatever. If you have that kind of heat budget available already then it won't matter, but if you're paying for air conditioning and you have to crank it down to make that happen then it's definitely going to feel as if it's making more heat.

People have done side-by-side grows in the same tent with LED and HPS and they usualy run it at the ideal LED temp to show you how shitty HPS is. So if you do this, whatever plant is getting all the IR light from the HPS is going to have up to 10F higher leaf surface temp than the plants that aren't lit by the HPS even though they're all in the same air temp. That plant with higher-than-optimal LST is going to suck compared to the ones next to it.

I like running lights that put out IR on an inkbird temp controller so that they warm up the room a little but don't overheat the leaves all the time. Any time my tent gets too cold my magnetic induction lamp kicks on until it comes back up to temp. I could just use a heating pad or space heater instead, but at least this way I'm also producing some extra light at the same time.

I have a total of 7 lights being used at the moment. In winter, they warm it up for me. Obviously this changes in summer. We have 2 seasons here even though they say 4. We get super hot and humid or super cold with ice. No in-betweens. I think I may try throwing a HPS system in one of my areas and see how it goes. Thanks for the info.

 

[hillbill]

CRI is based on incandescent light. Not the best light.

 

[Grow Lights Australia]

yes, and because of the direction of LED light most of it is absorbed by the leaves. if the photon is absorbed by a chloroplast it'll trigger a chemical bonding, and only a small fraction - the rest of the energystate of what's left over, is subsequently converted to heat. Ofc there are other materials there which can absorb photons that range in the visible spectrum which then can cause higher excitation states of baryonic matter.

However, the energy (heat) is not gone just chemically conserved - it will be released again upon decomposing. That's the reason why stuff thats decomposing heats up and can be used to drive a power plant.

And because LED puts out more PAR than HPS the emitted photons will create relatively more biomatter than initial heat.

Also, one reason to go for LED is to draw less power from the wall, so it makes not much sense to even compare the same tent-power-intake....

This is the best explanation I have seen in this thread.

Photosynthesis is an endothermic reaction and will absorb photon energy which is combined with carbon and water to form carbohydrates (sugars and starches) that are stored and used as energy inside the plant. So photosynthesis converts light energy into stored energy before the light energy has a chance to convert to heat energy.

One thing that perhaps hasn't been explained is the difference between infra-red and visible light. Both are forms of electromagnetic radiation. But visible light and infrared transfer their energy to mass differently depending on how the mass absorbs that energy.

This is especially true of water, which is what most living things including ourselves and plants are made up of.

Water absorbs infrared light at a faster rate than PAR (photosynthetically active radiation, which is mostly visible light from 400-700nm). That means the water heats up quicker. A similar principle applies to microwaves.

Here is the water absorption rate spectra. See how low it is in the visible light (and PAR) spectra compared to others?



This explains why infrared is "hotter" than visible spectra – even though visible light actually carries more energy. It has to do with the way that energy is imparted on different molecules.

And so HIDs convert more of their electrical energy into infrared than LED, which is why – watt for watt – they increase leaf temperatures at a higher rate. Leaves are mostly made of water.

However, one joule of energy per second – whatever that energy is (visible light or infrared) – is still a Watt. And so watt for watt, that energy is eventually converted to the same amount of heat. It's just a matter of time.

LED converts more of its energy to PAR – which the plant can absorb and store – and HPS converts more of its energy (compared to LED) to infrared – which is absorbed by the water in the leaf and converted to heat, which increases its temperature.

And that is why watts are not always watts.

I’m getting ready to convert from a 1000 watt HID to a 930 watt LED (at the wall). So this means that the LED will put off similar heat if run at full capacity?

No-one answered this, so yes – 930W of LED will put out a similar amount of heat as 1000W of HID. However, the heat will be absorbed at different rates.

More of the LED watts will be in the form of PAR, which the plant can use, and less will be in the form of infrared, which will increase leaf temperatures.

An even simpler way to put it is, if 700W of LED produces the same number of PAR photons as 1000W of HID, then you only need to put 700W of energy into the system for the same results (yields) – which means 300W less heat.