I've yet to read ask the links in this thread, but have just reviewed the Food Computer main board BoM, (11 months old, V1 ?).
I wanted to see (i) What is monitored, (ii) What is potentially controlled, (iii) Rough idea of energy consumption.
I've only guessed at what items would be the largest power consumers. Assuming only the three items below, let's say 350W max.
Energy consumption? I've no idea of the duty cycle of the heater and LEDs but made a wild guess at 40% ON time.
350 x 40% => 0.14KWh / Hr.
=> 3.36KWh / day.
=> 100KWh / month.
=> £15 / month (£0.15 / KWh).
Circulation / Vent Fans: 8W
Water Temperature + Conductance Sensor
Light Intensity Sensor
Air Temperature and Humidity Sensor
I looked for cheaper alternatives to some of the most expensive items, but couldn't find much improvement on what was already chosen. As others have predicted, the CO2 sensor is the most expensive item, at $109.
Eagerly awaiting any news of the V2 Food Computer BoM