Introduction: An Even "cooler" LED Grow Light

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today we will be putting together yet another LED grow light. a much cooler one..

cooling down grow lights are still the biggest issue, whether HPS, CFL or LEDs. most of the space usually goes towards this problem with either of these system. most of the cost also is created towards the solution, fans. lots of them..


LED grow lights have already proven themselves easier to cool down compared to other methods. my previous design; had to use fans to cool itself, due to the lack of a proper heatsink.

This time however I decided to use proper heatsinks, making the project fanless - also freeing up an outlet.!! new design is also more powerful, 12W to 16W. capable upto 20W using the same amount of space.. a huge improvement.



- 3x heatsink;

- 4x 660nm 1W;

- 4x cool white 1W;

- 4x warm white leds 1W;

- 1x led driver;

- 1x metal sheet;

- 1x ac cable;

- 1x switch (optional);


this new design is 16W, ~34V @350mA. it is $10 to operate 18hrs/day x365 days. and even less since there are no fans used anymore.

let's build>

Step 1: Measure

i need to be able to hang the light, and adjust its height as needed.


for this we need to make a frame first. I cut a piece of thin metal sheet using a drill and rotary cutter.


you could "glue" the heatsinks side by side using metal epoxy for your specific design. I could use a little distance between each light source..


i designed the cuttings in such a way that we should be left with nice little holders in place.

Step 2: Cut

first i used the drill to make lots of tiny holes along the cut lines, in pursuit of less rotary cutter time.. you can go either way for a cleaner cut.


after you cut the lines, bend the little flaps upwards using plyers.


it is going to be a tight fit, slowly try to place the heatsinks into the holes. make sure to cut less at first if you arent sure about the dimensions, you can always go back and cut more. much easier to fix..


Step 3: First Trial

also drill 4 holes for the carrier wire.


attach some garden wire to each hole and hang where needed..

Step 4: Wiring

here is the wiring diagram of the LEDs, solder everything in series.


using very little thermal glue place each led on the heatsinks. these heatsinks are supposed to work with 5x 1W LEDs. 24/7 x365days ON.


however I chose to use 4W/heatsink to get better cooling, and left the middle of each heatsink empty as I may upgrade to 5W/heatsink in the future.


there are many heatsink options out there, you can get

single 1W heatsink;

or upto +20W heatsink;

using them side by side etc, one can design a very effective and sleek grow light.

Step 5: Conclusion

the heatsinks do get warm, as i leave them on for long periods of time.. i am yet to test the actual temperature with an IR thermometer. will update here once done.!


i am in the process of updating box1; - i need a simpler, a more sleek look. allowing more space left for what really matters, plant growth.


I will be making more prototypes using other styles of heatsinks available as well, subscribe to stay updated. I also am going to try to use peltier thermoelectric cooler/heaters.


love & peace