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LED Grow Results: Grams per Watt

M

Milhouse

Hey GP, just want to say that you are doing a great job compiling this info in a centralized thread. I am sure this thread will become reference to many a future growers. Keep up the good work.
 

GP73LPC

Strain Collector/Seed Junkie/Landrace Accumulator/
Veteran
thanks Milhouse,

my reasoning on this thread is two fold...

1. provide documentation to non-believers that LED's do have what it takes to grow killer weed.

2. a collection of links to LED grows


to me, LED's are the way to go
- no heat
- longer life
- very efficient (no unused spectrums)
- about half the wattage needed per sq ft (as compared to HID)

startup costs is the con. but prices should come down over time...
 

GP73LPC

Strain Collector/Seed Junkie/Landrace Accumulator/
Veteran
Those lights draw an actual wattage of 55 watts, and the strain he was growing was described as a medium yield one. With descent lights and a very skilled grower, over 1 gram a watt is achievable.

Good lights are expensive but the results are good right now.

well then a 1.07 gpw rating is in order for that grow...

:thank you:
 

flat3ric

Member
Re: LED Grow Results: Grams per Watt

Gpw is really quite a useless parameter. Grams per Watt hour tells you a lot more

Sent from my ADR6300 using Tapatalk
 

GP73LPC

Strain Collector/Seed Junkie/Landrace Accumulator/
Veteran
Gpw is really quite a useless parameter. Grams per Watt hour tells you a lot more

Sent from my ADR6300 using Tapatalk

please explain...

i did find this information which basically adds time to the equation

GARDEN EFFICIENCY RATING - Online Calculator

How much juice you burn to grow a gram..

Standard methods of reporting garden yields are imprecise and don't take the factor of time into account. This is a summary after discussion on a new standard formula for reporting yields and efficiency.

The GE Rating is based on the amount of kilowatt hours used to produce one gram. This factors in how long your strains flower and the resulting number makes it simple to compare 4000 watt gardens with 400 watt gardens. The calculations are easy, here is an example:

2000 watt flowering area
60 days of flowering
12 hours on light cycle
total yield: 49.5 ounces

1) Divide the total wattage of your lamps by 1000 to determine the kilowatts per hour:

2000 / 1000 = 2 kw/h

2) Multiply the previous result by the hours of the light cycle (usually 12):

2 x 12 = 24

3) Multiply the previous result by total days in flowering to determine how many kilowatt hours you used:

24 x 60 = 1440

4) Make sure your yield is in grams, so:

28.4 x 49.5 ounces = 1405.8 grams

5) Now simply divide grams by kilowatts:

1405.8 / 1440 =

0.97 grams per kilowatt hour, or a GE Rating of 0.97! Good job to the hypothetical grower, approaching a GE of 1 is the first plateau to be reached and is a sign of an experienced grower.

Is this what you are referring to?

I don't have flowering times on these grows so I can't figure that out. Since the standard for an experienced grower seems to be 1 gpw using HID lighting, I am going to use that same standard for LED lighting.

With that said, the GE Rating method definitely factors in energy usage so I can see that it is more accurate than just GPW...
 

FreedomGrower

Active member
Veteran
Hope you don't mind me adding some theoretical limits / cost break downs of the tech so far ...

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GP73LPC

Strain Collector/Seed Junkie/Landrace Accumulator/
Veteran
where did you get the chart?

i trying to take it all in and understand it all...

does the line for the chinese 3w led mean it is 1000 watts like the HPS?
 

FreedomGrower

Active member
Veteran
I made the chart .. I'm a math minor ... looked up the specs of common led brands and cranked out the theoretical ...

Light type is the brand of the L.E.D being compared

And yes 1000watts of Chinese 3 watt led's put out almost the same amount of usable lumen s as a 1000watt hps.

This does not take into account; penetration; optics; spacing; design; or growing style; Just usable lums output of the led brand

Also some more info on some others; These work well because they use lenses

357 magnum and the Penetrator Led S use (40lum a watt (old design bridgelux)

all specs are based off of one watt
Also some info for DIY
http://www.philipslumileds.com/products/luxeon-rebel/luxeon-rebel-color#red

http://ledsupply.com/led-catalog.php
http://www.ledsupply.com/docs/reef-tank_diy-instructions.pdf


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GP73LPC

Strain Collector/Seed Junkie/Landrace Accumulator/
Veteran
well i like it... ;)

very, that's what the math says will happen :good:
 

#1cheesebuds

Well-known member
Veteran
I have a quick question for yall.

If I bought a 90watt ufo light would it be the better choice than my now 221 watts of cfl lights. and I cant get the temps blow 93. even with three fans in there. ):

so what would u go with. space size is 3wx3dx4h.
 

FreedomGrower

Active member
Veteran
Well your cfls are putting out about 3500 usable lums

So it depends on the led brand the ufo is using (Chinese ufo no; blackstar about equal )
this should be comparable or better (note I hv never used one based off specs alone)
http://cgi.ebay.com/120W-Dual-Band-...332?pt=LH_DefaultDomain_0&hash=item20b62d8294

Also if anyone is wondering; I plan on adding these around my hps lights pointed at colas .... 60lm a watt red
http://www.ledwholesalers.com/store/index.php?act=viewProd&productId=710

Only decent commercial LED on the market ... using the new Philips luxon rebels

http://www.globaltechled.com/led-grow-light.php

http://cgi.ebay.com/NEW-270W-LED-SO...674?pt=LH_DefaultDomain_0&hash=item1e6085c26a
 

GP73LPC

Strain Collector/Seed Junkie/Landrace Accumulator/
Veteran
I have a quick question for yall.

If I bought a 90watt ufo light would it be the better choice than my now 221 watts of cfl lights. and I cant get the temps blow 93. even with three fans in there. ):

so what would u go with. space size is 3wx3dx4h.

I think the UFO could come close in optimal conditions.

I also think it should produce less heat, but I will let a UFO owner provide you more info as I have not used one...
 

asde²

Member
freedom grower:
what is lum efficiency (my guess: watts in light output% / electrical watts input%)?
what is wav efficiency (my guess: the 15% value led panel sellers used already 5 years ago..! but they never learned statistics - their 15% statement is 100% false)?

basic 600w hps efficiency is ~0.35W/1W, hps spd efficiency is above 60% when growin plants in general
no matter what i try, i cant get close to any of your numbers..
 

FreedomGrower

Active member
Veteran
Luminous efficacy is a measure of how well a light source produces visible light
http://en.wikipedia.org/wiki/Luminous_efficacy

Wav effectiveness is the lums the plants can actually absorb ... aka 440-490nm blue and 600-690nm red

To a gram a watt with hps your room has to be dialed; AC; C02 or good air; Nutes; Genetics; etc

Those are the gpw theoretical highs we have with the high yielding strains; Not all genetics can yield this much; og's avg around .5 gpw and chems around .75-.9.

Same with LED

Mr-x is already getting 2gpw with cree leds
with Chronic

https://www.icmag.com/ic/showpost.php?p=4530221&postcount=85

https://www.icmag.com/ic/showthread.php?t=215147&page=4


below is a pic of one of my 1kw hps grows that got a gpw xxxl hood (It's allot of herb); If you don't have a good hood it's guna be like running Chinese leds :) but with a hps
 

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