I would like to measure the amount of power that is delivered by the Sun during the day. I have a nice housing (a waterproof glass hemisphere with aluminium base) from an outdoor IP camera and have been thinking about putting small solar cell in it.
I know I can calculate DC power in Watts as P = UI and knowing the area of the panel, calculate the amount of immediate power that is being delivered to a square meter. (And I would need to know the panel's efficiency.)
Sure enough there are devices to measure power yield of a solar panel, could anyone explain how these operate so that I can build myself one?