Mini Green House

Green house is misleading, it's a seed starter pod for the basement. I have the light, I just need an insulated box.

Ok, so I did that and I don't like it. I want to do this with LEDs.

Build

1. Get measurements 50"x18"x32"
2. Layout design, get cut list
3. Find spare timer
4. Buy insulation
5. Cut insulation
6. Assemble
7. Add blower
8. Gather temp data

Heater Circuit

Only if necessary. Or if I really want to. But don't let it be an impediment to something good-enough

Use an RTC module and an Arduino. The RTC module will wake the Arduino every 10 minutes. If the temp is too low, it will turn on a small heater. It will also check the time and turn the light on or off as needed.

The heater can be pretty simple, just run a few volts through a power resistor and blow a small fan over it. At 5v and 0.75A I can use 8x 50 Ohm 1/2W in parallel That will handle 4 watts.

The light is a bit more of a challenge because I need a latching power relay. I also need a way to check the state of the light, not hard, but there's a few ways to do it. It might actually be easier to hook a servo up to a light switch.

Components

• Blower to circulate air
• Heater
• Light control

Build

• Start by just building the box - the light might be enough to keep the plants warm
• Add a fan - the air movement helps build stronger stems
• If the temperature is getting too low, add a circuit.

V2

• Power
• LEDS
• Fan
• Power resistor
• Power supply
• RTC
• Arduino

All electronics go inside the box. I don't need to worry too much about efficiency because heat is an issue.

LEDs

I can get an LED panel for about $25, but I'm not sure I trust those.

Plants have A and B chlorophyll see here

• A: 430nm and 662nm
• B: 453nm and 642

https://www2.mcdaniel.edu/Biology/botf99/photo/p3igments.html

So I want LEDs with peaks around those values. They should use about 50-80 watt/sqft