I bought some 1.75W/0.5V cells from ebay. Aim is to make small (proto) off-grid system for next summer. Total power would be around 100-150 W. I am also designing mppt charge controller for this, but as it happens I dont have any earlier experience with PV systems.
For this reason I need to know some basics from PV. How much voltage fluctuates as weather changes. What should be the oc voltage be in 12V system? I understood that PV acts like current source where amperage stays the same while voltage travels. Is this so?