LEDgardener

Do you think that a 180 mm heatsink can cool 150w of vero29
I can not find thermal information for this heatsink

i did try those heatsink on cree cob cxb 3590 at 100w and they were at 58 degres celsuis with no fan.
i dont think they will handle safely 150w without fan.
cheers

If you are running a COB at 150 W you should really have a copper heatpipe system with a copper base for the COB to be mounted on. My other recommendation is to either use screws or a bender&wirth COB holder. A good heatpipe COB heatsink is expensive and it's better to use 3 standard heatsinks and 3 COBs running at 50W each, not only will this perform better it will also provide a much larger spread of light across the canopy

I was looking at active cooling options at digikey, and many of them seemed pretty solid with 100000h min. lifespans... I was wondering if the DIY crowd didn't ditch active cooling because of the bad rep cheap chinese lights created?

Passive heatsinks are pretty cheap @50W and bullet proof. Things change really fast when powering a COB over 50W, it really isn't necessary to go beyond 50W per COB in a grow room in a small area. The problem is to do with spread. A COB just doesn't have enough of it without running special optics. So you have no choice but to raise a light higher to get the spread you need when running 100W of COB. If you run 2 50W COB lights you double the spread. It's more economical overall to run more COBs than a few big ones simply due to the fact you can sit them closer to the canopy to get higher par values.

I saw there were a lot of models that would remove at least up to 35 heat watts.. I don't know much about cobs, and was actually looking for solutions for cobs that would have run at around 20w each, total power...