Open Source Indoor Greenhouse

[vmproperly]

In the style of Garduino, I have started a project to help automate gardening. There are controllers on the market for doing this, but they are currently very expensive:

XGC-1e - Xtreme Greenhouse Controller
Price: $563.19
The Complete Greenhouse Controller and the Xtreme Greenhouse Controller handle every aspect of an indoor garden, from the lighting and exhaust, to the supplemental CO2. The Complete Greenhouse Controller features a 24 hour time clock, 2 outlets for lights, 2 outlets for exhaust fans, thermostat and humistat for temperature and humidity control, 2 pump outlets controlled by a cycle timer, and 2 outlets for supplemental CO2 controlled by a cycle timer. It ensures that CO2 production turns off while the exhaust is on and at night.

I would like to design a product which can provide these features, AND control lighting, AND have a bluetooth / remote interface… AND be half the cost.

This will be a system to control fan-speed control, ventilation, LED lights, temperature, humidity and CO2. The brains of this unit is the Bluetooth Bee Standalone.

AC Fan-Speed Control:

Ventilation:
This system should be able to control cooling for the lighting system and ventilation for the main greenhouse space; this can be accomplished using just 1 fan, a y-duct adapter and an electronic duct damper. This will require a small mechanical relay. The fan speed itself will need to change depending on the temperature, humidity and CO2 levels. I was thinking of using a Triac or a Variac for this. A triac controller is cheaper, but variacs are able to slow a fan without causing it to hum. Advice needed on this point. Controlling DC fans is a lot easier – but I am not familiar with DC fans for inline ducts.

CO2 Control, Water pump control
Simple mechanical relays can be used to control the CO2 generator and hydroponic water pumps.

Lighting:
Ideally, this system will be able to control 300W of LEDs. 2 x 100W RGB LED and 100W of 120/m RGB strip lighting. The 100W LED diodes are composed of 440:430:630:660:535 crystals in a ratio of 2:1:5:1:1 – currently sourcing these from JXGLED in Shenzhen for $98 each (if you can help me negotiate a better price for sample LED diodes, let me know!). The LED strip lights are for under or side canopy lighting, and for germination / seedling lighting.

The 440 and 430nm crystals are for the growth of seedlings and vegetative growth - while the 630 and 660nm lights are for when the plant is in bloom or fruiting. The 535nm light is for the convenience of the gardener; green combines with red and blue to create a more natural white-ish light - which is important for ascertaining the health of one’s plants. In addition, green light does not affect a plant’s “sleep” during the dark photoperiod.

I am hoping that I can control at least 5 discrete lights using just one LED driver. The specifications for the 100W LED are Blue: 30-36V/1400mA Green:30-36V/350mA Red:20-26V/1750mA

Environmental Sensors
Air Temperature + Humidity sensing is provided by the standard Grove T&H sensor. Water temperature (for hydroponic reservoirs) can be sensed using a cheap temperature chip and some silicon sealant. It looks like I will be doing the CO2 sensing using a MG811. I am hoping the price for this component will drop.

Interface
This system should be fully controllable both remotely over bluetooth, and locally using a dial/buttons and a green LCD.

Fuzzy Logic
All of these components will be tied together by the Bluetooth Bee Standalone + an RTC chip.

[vmproperly]

I just put in my order for T&H sensors and the Bees Shield. Does Seeed have any plans to offer CO2 sensors?

[vmproperly]

Furthermore - I want to keep this project as modular as possible. The idea is that the user will be able to buy a standard kit for controlling temperature and lights (simple mechanical relay, not LED lighting control) and expand or repair it herself using “Grove” style modular components.