For years, I've had problems with my houseplants (mostly chiles, but also some citrus) perishing over winter indoors. I had chalked it up to just having a black thumb, but my roommate thought it was insufficient light. So we started just turning on a desk lamp at night to shine on the plants. Lo and behold, that seems to be it! The plants are now beginning to grow new baby leaves to replace all the ones they shed. So I began thinking about building some kind of grow light, probably using LED strips as the light source.
Anyway, I stopped at a local electronics shop to pick up a broken LCD monitor I had intended to salvage optical films from for
a different project. The 32 inch TV that was all they had in their junk bin ended up not having the optical films I needed. But its old-school CCFL backlight box is the perfect size and shape to make a light panel to illuminate the plants, and has a lovely thick, robust diffuser panel. Unfortunately, the power supply board in this TV appears to be shot (I suspect that's why it was thrown out to begin with), so I can't use its CCFL lighting to hold me over until the LED strips arrive.
So my plan at this point is to rip out the CCFL tubes and glue a bunch of LED strips inside. The Tim the Toolman Taylor in me of course wants to line the thing completely with LEDs, but a back of the envelope calculation said that'd be about 240 W, which would probably set the plants on fire. A more realistic plan is to line it with two different types of LED strips:
white LEDs for when humans are inhabiting the room, and red and blue ones as more energy-efficient grow light for when it's just the plants. (I actually found some neat LED strips on eBay that contain dual-color warm white/cool white LEDs so you can tweak the color temperature.) I was thinking that somewhere in the ballpark of 30 W each for white and red/blue would be more than enough.
I know that in theory I could use RGB LEDs to cover both use cases, but I really hate the sickly white of RGB, which is why I want to have the option of true white LEDs.
Other than making sure I have an adequately specced power supply, is there anything I'm missing? I haven't decided whether to use off-the-shelf remote control modules, a bank of manual power switches, or even an Arduino to control the brightness. I'm open for suggestions if anyone has experiences to share.
On the subject of power supplies: obviously you can get cheap Chinese made power supplies, but that's probably a bad idea. The
local electronics distributor sells both open-frame and laptop-style power supplies from both TDK-Lambda and Mean-Well. The cheapest models don't have great efficiency, and they don't specify there no-load power draw. Would I be correct to assume that it's higher than the <0.5 W no-load power draw specified in the better models? Are there any advantages or disadvantages of one brand over the other, or of open-frame versus laptop-style?
Edit: Added bolding to show people that I am very aware that white LEDs are inefficient for photosynthesis, since people keep reminding me of this despite me explaining repeatedly that a) I know this, and b) the reason.