Can LED's do a pound or better per harvest?

[Kill a Watt]

leds certainly can produce. the light penetration isn't as good as hps so the top i'd say 8" get the best light. however, where light penetration isn't as deep, it is made up with selected spectrum so light your not getting spectrum IE in the 500.

 

[Crooked8]

Ppl really get a gpw out of leds? With no heat? Why do most ppl use 1k hid then?

 

[DZLHIT]

Ppl really get a gpw out of leds? With no heat? Why do most ppl use 1k hid then?

Mostly because most people already have HID, and also because LED is more expensive upfront to cover the same area.

I have both, and the LED rocks.... still new to me though. My goal is to pull a pound from 300 watts of LED, in a 3x3

 

[Sativa Dragon]

Candlepowerforums has debunked the LED vs HPS efficiency long ago.
There's not much difference. Both come in around 25-30%. The rest is wasted heat.

If you think a a HID and an equivalent LED dont generate near the same amount of heat, your kidding yourself.

A 600w LED grow will produce about 450 watts of heat.

^^THIS IS WHAT I MEAN^^

See I am not a hater just trying to say exactly this ^^^ is what I experienced in my Test with LED's

Peace

 

[GP73LPC]

see my post in the retailer thread

 

[Phaeton]

Been gone awhile but the budroom never quit.

HIDs heat up the walls, tables, floors, and ceiling. Air has to pull the heat from the surfaces to get it out of the room.

A 600w LED produces 600w of heat, a 600 watt HID produces 600w of heat, that is what a watt measures.

An LED is cooled by a finned radiator heating up the air circulated around it. The 600w of heat goes directly into the air and merely needs to be routed out of the room.

An HID radiates heat into all those surfaces mentioned and they soak up the heat and hold it, requiring cool air to circulate throughout the entire room pulling heat from the surfaces before exiting.

Wow, that is an awful lot more air and the heat has to be handled more than once.
This is why they say LEDs run cooler, not because it is true but because the heat is so much easier to manage it just seems as if there is less of it.

2240 watts of HGL and 714 watts of Magnum, plus still have 2000 watts of CMH and 3100 watts fluorescent.
Did a few years testing stuff for fun. Kept the lights and still use them.

Now that the Poppy research is done I can talk on this forum again. Some plants are frowned upon.
At 6 KWH per mg of yield I can see why indoor poppy is not popular. LEDs make it possible if not practical.

The poppy was mentioned because it takes 2.5 times as much energy to grow as MJ, giving lots of experience in handling heat.

 

[GP73LPC]

thanks for your input phaeton.

very well put

 

[devilgoob]

Originally Posted by GP73LPC:
LED's give you much, much less heat (as compared to hps), much longer life, more energy efficient due to no wasted light spectrum, short tight nodes and according to some, frostier buds...

you have no worries about FLIR, you have no hps heat to dissipate, no bulbs to replace every 1-2 yrs and you have lower temps in your grow room.

i know start-up costs are prohibitive for a lot and that is really the biggest argument against LEDs.

With life expectancy at 10 yrs+, to me the cost of LEDs is worth it. When you consider the price of extra cooling for the grow room and hps light, energy used for additional fans because of the hps, bulb replacement costs, being visible to FLIR (only if running enough watts) and plenty of wasted light spectrum, those costs may in fact add up to or exceed the costs of the LEDs. i guess that really depends on each individual setup and grow room.

anyway, enough rambling from me...

keep the votes coming in.

Whoever said watts are heat, is right. Watts are also defined by V x A. Which is voltage and amperage's product.
Well, that would be the what is released convection-wise, and the light output flux. The LED to the heatsink...or HPS to air. So we get rid of the heat, almost all of it.

Although a lot of people mull around this question..I will just say it...once I say it..you will know I am the devilgoob.

The LED's put out usable light at two frequencies. The HID's put out light we can't see and also IR light, which heats up water.

What I mean is, the HID radiates light, the plant gets hot and acts as a heatsink and that's why even with it hood-cooled it still is warm. The plants act as radiators that get rid of the excess heat created by far-red heating of the plant.

So it's radiative warming, then convection off the plants.

From Wiki:

-Rotational transitions, in which the molecule gains a quantum of rotational energy. Atmospheric water vapour at ambient temperature and pressure gives rise to absorption in the far-infrared region of the spectrum, from about 200 cm−1 (50 μm) to longer wavelengths towards the microwave region.

-Vibrational transitions in which a molecule gains a quantum of vibrational energy. The fundamental transitions give rise to absorption in the mid-infrared in the regions around 1650 cm−1 (μ band, 6 μm) and 3500 cm−1 (X-band, 2.9 μm)

-Electronic transitions in which a molecule is promoted to an excited electronic state. The lowest energy transition of this type is in the vacuum ultraviolet region.

Here is a link of the frequencies more absorbed
http://upload.wikimedia.org/wikipedia/commons/8/8d/Water_light_absorption_coefficient.gif

 

[Sativa Dragon]

If I put my hand infront of my 1k LED fixture I can feel radiant heat.

Why is that?

Peace

 

[Phychotron]

the light hits your hand then bounces off at a lower energy level, leaving heat behind...

 

[babelfish]

First Greetz. Luv the thread, love the goal, hope to join y'all soon in it. With this in mind my opinions of the subject and not any individual follow.

Been gone awhile but the budroom never quit.

HIDs heat up the walls, tables, floors, and ceiling. Air has to pull the heat from the surfaces to get it out of the room.

A 600w LED produces 600w of heat, a 600 watt HID produces 600w of heat, that is what a watt measures.

An LED is cooled by a finned radiator heating up the air circulated around it. The 600w of heat goes directly into the air and merely needs to be routed out of the room.

An HID radiates heat into all those surfaces mentioned and they soak up the heat and hold it, requiring cool air to circulate throughout the entire room pulling heat from the surfaces before exiting.

Wow, that is an awful lot more air and the heat has to be handled more than once.
This is why they say LEDs run cooler, not because it is true but because the heat is so much easier to manage it just seems as if there is less of it.

2240 watts of HGL and 714 watts of Magnum, plus still have 2000 watts of CMH and 3100 watts fluorescent.
Did a few years testing stuff for fun. Kept the lights and still use them.

Now that the Poppy research is done I can talk on this forum again. Some plants are frowned upon.
At 6 KWH per mg of yield I can see why indoor poppy is not popular. LEDs make it possible if not practical.

The poppy was mentioned because it takes 2.5 times as much energy to grow as MJ, giving lots of experience in handling heat.

Actually the difference is WASTED energy.

Whoever said watts are heat, is right. Watts are also defined by V x A. Which is voltage and amperage's product.
Well, that would be the what is released convection-wise, and the light output flux. The LED to the heatsink...or HPS to air. So we get rid of the heat, almost all of it.

Although a lot of people mull around this question..I will just say it...once I say it..you will know I am the devilgoob.

The LED's put out usable light at two frequencies. The HID's put out light we can't see and also IR light, which heats up water.

What I mean is, the HID radiates light, the plant gets hot and acts as a heatsink and that's why even with it hood-cooled it still is warm. The plants act as radiators that get rid of the excess heat created by far-red heating of the plant.

So it's radiative warming, then convection off the plants.

From Wiki:

-Rotational transitions, in which the molecule gains a quantum of rotational energy. Atmospheric water vapour at ambient temperature and pressure gives rise to absorption in the far-infrared region of the spectrum, from about 200 cm−1 (50 μm) to longer wavelengths towards the microwave region.

-Vibrational transitions in which a molecule gains a quantum of vibrational energy. The fundamental transitions give rise to absorption in the mid-infrared in the regions around 1650 cm−1 (μ band, 6 μm) and 3500 cm−1 (X-band, 2.9 μm)

-Electronic transitions in which a molecule is promoted to an excited electronic state. The lowest energy transition of this type is in the vacuum ultraviolet region.

Here is a link of the frequencies more absorbed
http://upload.wikimedia.org/wikipedia/commons/8/8d/Water_light_absorption_coefficient.gif

You did good son.

https://en.wikipedia.org/wiki/Watt
One watt is the rate at which work is done when an object's velocity is held constant at one meter per second against constant opposing force of one newton.

In terms of electromagnetism, one watt is the rate at which work is done when one ampere (A) of current flows through an electrical potential difference of one volt (V).

Two additional unit conversions for watt can be found using the above equation and Ohm's Law.

Where ohm () is the SI derived unit of electrical resistance.
Examples[edit]

A person having a mass of 100 kilograms who climbs a 3-meter-high ladder in 5 seconds is doing work at a rate of about 600 watts. Mass times acceleration due to gravity times height divided by the time it takes to lift the object to the given height gives the rate of doing work or power.[notes 1]
A laborer over the course of an 8-hour day can sustain an average output of about 75 watts; higher power levels can be achieved for short intervals and by athletes.[1]
A medium-sized passenger automobile engine is rated at 50 to 150 kilowatts[2] – while cruising it will typically yield half that amount.
A typical household incandescent light bulb has a power rating of 25 to 100 watts; a similar amount of light would be produced by fluorescent lamps at 5 to 30 watts, or LED lamps at 5 to 20 watts.
A typical coal power station produces around 600–700 megawatts. A typical unit in a nuclear power plant has an electrical power output of 900–1300 megawatts.

the light hits your hand then bounces off at a lower energy level, leaving heat behind...

better - yes better.

We are talking in terms of work. The work the ballast on the led/hid does. when it does conversions of energy inefficiently, we feel it get hot.
When our LED's run and they get hot they push heat to the top and fans blow it away.
When our HID's get hot they radiate a lot of heat.

The point is WHAT that energy goes into. Atoms can absorb photons. Sometimes they give off a photon as well. sometimes no chemical work can be done by the incoming photon and its energy gets wasted in normal kinetics.

It all goes to heat eventually, but the point is that not all of it has to.

If led's push 90% of their energy directly into the area the plants can use, and have a dense canopy to radiate at, it makes complete sense that this TARGETED radiation would be more effective per watt than HPS. good ballasts with good led's SHOULD have less waste heat based on an equal pull @ the wall.

But as other systems bleed - some of this heat gets released back.

Its called entropy.

namaste~

 

[Sativa Dragon]

Got to love science... When I am outside on a sunny summer afternoon I can literally feel the sun on my skin this is radiant heat that heats everything up around me as well, would it not be safe to say that the plants that are outside all day everyday enjoy this radiant form of heat? Perhaps they have evolved some ways to deal with the heat, or even more interesting would be if they actually did better in some cases because of the full spectrum sunlight with the heat.

Peace

 

[DZLHIT]

Got to love science... When I am outside on a sunny summer afternoon I can literally feel the sun on my skin this is radiant heat that heats everything up around me as well, would it not be safe to say that the plants that are outside all day everyday enjoy this radiant form of heat? Perhaps they have evolved some ways to deal with the heat, or even more interesting would be if they actually did better in some cases because of the full spectrum sunlight with the heat.

Peace

They do need heat to perform their activities, but it is the EXCESS heat which people are speaking of. Heat people pay $ to remove from their space.

In the winter I have to run a heater with my LED tent, the plants don't like 58 degrees. A lot of other people do the same.

 

[Avinash.miles]

some good info floating around this thread...
thanks yall

im barking up the leg of an LED company for a tester model.... hoping to do a lil trial with an LED.

 

[Sativa Dragon]

I do not want people to think of my questions as facetious, it is a better way for me and hopefully others to understand the pro's and con's of LED's I admit to being a flip flopper on this subject.

I find myself being seduced by the abilities of HID's and forgetting there was a learning curve to start with initially when starting to use them, mainly being dealing with heat.

I am convinced now that technique is a major player when switching from HID's to LED's.

From the reading and research of available technology recently I have seen a lot of new stuff I haven't seen before like 100watt LED's, I ignorantly argued HID's are king.

Granted the Technology I speak of is still expensive it will only be a matter of time before manufacturing costs come down to make said technology readily available to the middle class.

I have had success blending some 430nm LED's with 3000k CFL's

Thanks for promptly providing solid answers.

Peace

 

[jcmjrt]

In the winter I have to run a heater with my LED tent, the plants don't like 58 degrees. A lot of other people do the same.

Yep, something I had to learn on my first winter grow too. I was a little suprised at ending up with too-cool heat issues.

I've thought about adding back in a T5 or CFL or something else next winter grow so that I'm getting some light for my watts as well as the heat. Mine were having some growth issues at 65 degrees -- 70 - 80F seems to be a great zone.

 

[Phychotron]

I am convinced now that technique is a major player when switching from HID's to LED's.

I believe this is the number one cause of discontent with LED's. It seems to be the experienced HID people that dislike LED's because they're methods are all geared toward that HID--variables change and their methods don't--but they expect the same results.

 

[devilgoob]

If I put my hand infront of my 1k LED fixture I can feel radiant heat.

Why is that?

Peace

http://upload.wikimedia.org/wikipedia/commons/8/8d/Water_light_absorption_coefficient.gif

Cause, the chart man.

LED's using primarily 660nm red still heats up stuff @ .5. Which is just a coefficient of absorb of water to that wavelength of light. That is the water in the plant, I mean.

HPS's put out "above red"...infrared or IR, which heats water at a coefficient of @ 1.4. Which is about three times the heating power, and considering HPS's have even more of this light in this region, and it heats water, then the plant will be a higher temperature. This eventually convects off the leaf, some of it is radiated, but I would like to think it increases transpiration of the plant, making it breath more.

Yes, warm whites and HPS I ponder, increasing the stoma opening and closing and by creating less water in that area, that more water (down there) is drawn into the roots. It drinks faster, and that could be a good thing HPS has over LED.

Only some warm white's push their spectrum past 660nm sufficiently, but I would say efficiently cooling your lights and not lighting or heating a plant will leave you with a cold plant. Usually people are battling temperatures, but temperature increases movement, increases processes speed. LED's sometimes don't heat.

I would get some heat pipes and use cut up cans, drilling holes in the discs and slipping them on with silver thermal epoxy and then run it under a seed tray. You could cool your LED's and heat the tray underneath. Maybe just a seed starter.

LED's put out radiant heat to 660nm and maybe a few 730nm for far-red, the plant gets all heated and releases it convection-wise or through stomata. They are all also directly-sinked.

But the HPS/MH's spectrum does not drop off there, and starts to become much more a heater of a plant.

LED's have a directional problem!

I say take bendy-tubes and route wires to diodes attached to heatsinks and draw the air from the tube which holds the power wires for the diodes that attach and bend the where you want.

You could create movable diodes in a computer with just simple magnets on each ones, creating customisable bud spot lights that you can move as the plant grows.

No, wait!

You take the CXA 3xxx series at 30 watts, reclaim most of the 30 which was released as heat, instead of light,and use that to generate wattage with 4 peliter units and add your new 10 watt LED unit!

OR YOU COULD.

Take a few plants and suspend them with a magnetic bearing. Yea, you could have one giant magnet opposing another one, holding that one up, and then a few donut magnets stabilizing it.

So it's magnetically up there. Now you attach a bunch of solar panels or reflectors and put computer fans around the pots.

Depending on how fast these computer fans powered by the solar panels on the pots spins your entire grow, it will train inward toward your light just like a stadium grow.

It's because you're training it with the g-force of gravity, which all stadium grows ignore.

 

[GP73LPC]

thanks for all the input on heat LED vs HID everyone, good stuff

 

[babelfish]

hm lumi swears the 325 pro is the same as a 1k, i might just test em on that.