It was already last year that I started planning a simple solar power system for the greenhouse, since the next power outlet is a tad bit away. After much back and forth, I finally dug up enough time and nerves to complete it by the end of may.

The plan was to create enough electricity and storage capacity to power a computer fan (for at least basic air and humidity exchange) and a small LED-Light. In the long run, I hope I can set up one of those timer-controlled solar irrigation systems (which will have to wait until I have installed a proper water reservoir close to the greenhouse). I even added an empty 220V socket should I ever run a decent cable back there.

It works very well so far, though I doubt the repurposed motorcycle battery I used will be powerful enough to power all three appliances when there’s no sun for a few days. We’ll see. Now that the days get hotter I have the impression that at least the fan is doing a good and reasonable job. See the details below.

Wiring Diagram:







Solar Panel   Charger Module
Rated Power 30Wp   Rated Voltage 12V/24V
Max. Power Voltage 18,0V   Rated Current 30A
Max.  Power Current 1,67A   Max. PV Voltage 50A
Open Circuit Voltage 21V   Max. PV Input Power 390W(12V) / 780W(24V)
Short Curcuit Current 2,0A      
Max. System Voltage 600V      
Battery 12V/10Ah