Have any of you DIY COB Growers finished a crop under 1000W DE HPS? - POLL

[wietefras]

I prefer to keep it pure umol vs umol and not speculate about spectrums.

Don't forget the wall losses. With a HPS hanging 3' above the canopy, you lose a lot of light on the walls (or floor if there are aisles). So after initially already losing a minimum of 17% on the HPS reflector you will lose something like that again because of the wide angle beam and height.

You're lucky to get even 1.3 to 1.4umol/J from that HPS actually on your plants.

COBs can be much closer and even without optics their beam is much narrower. So much less wall losses there. and with COBs there is usually no need for reflector losses at all. So already there you will gain a lot on HPS. Even if the umol/J is the same.

Leds are also multi point lights giving much more diffuse light than HPS. Which means better penetration.

I have fixtures with old CXB COBs running at only 2umol/J and 800W of that already equals in harvest what I got from my Gavita DE boosted to 1150W (around 1200g). At 2.8umol/J really 550W to 600W should be enough to match that DE fixture.

 

[CannaBruh]

Don't forget the wall losses. With a HPS hanging 3' above the canopy, you lose a lot of light on the walls (or floor if there are aisles). So after initially already losing a minimum of 17% on the HPS reflector you will lose something like that again because of the wide angle beam and height.

You're lucky to get even 1.3 to 1.4umol/J from that HPS actually on your plants.

COBs can be much closer and even without optics their beam is much narrower. So much less wall losses there. and with COBs there is usually no need for reflector losses at all. So already there you will gain a lot on HPS. Even if the umol/J is the same.

Leds are also multi point lights giving much more diffuse light than HPS. Which means better penetration.

I have fixtures with old CXB COBs running at only 2umol/J and 800W of that already equals in harvest what I got from my Gavita DE boosted to 1150W (around 1200g). At 2.8umol/J really 550W to 600W should be enough to match that DE fixture.

good points

 

[ttystikk]

Upfront cost is more with LED
Upkeep cost is far greater with conventional HID

Currently, this is true. It won't be true for much longer.

That's no reason to wait to buy LED light fixtures because as soon as you do, they start saving you money. At the price and quality now available, you'll always save more buying them over traditional lighting.

 

[applepoop1984]

well remember that hps uses 1100+W and on a system efficiency is only pushing 1.7 umol/J gross with less than ideal coverage.

with a far better spectrum i think 550W at 2.8 umol/J might approach the results of 1100W 1.7 umol/J - spectrum could give a 10% or more edge to the QB fixture

a 600H instead of a 480H driver pushing it certainly would, but then we're talking 750W

Could you recommend a setup for me? It's a 2 foot by 2 foot by 4 foot high grow tent

 

[Evil-Mobo]

Could you recommend a setup for me? It's a 2 foot by 2 foot by 4 foot high grow tent

(2) of his single COB engines running 50-60 watts each.............I'd go with Citi 1212's unless the new CMX's offer any benefit.

I run (2) 1212's in my veg closet that's 2x4.............

 

[applepoop1984]

How much do you think that setup would cost

 

[Evil-Mobo]

How much do you think that setup would cost

I can't answer pricing for @CobKits send him a PM. Because he sells them with and without a driver and that changes the cost.

His website is here:
https://cobkits.com/product/clu048-1212-active-light-engine-single/