A solar circuit is presented here is… a device for collecting sunlight. To keep things simple, we’re using a single nicely made small solar panel for all of these circuits. The panel that we’re using for these circuits can be procured from Dx.com for as low as Rs325/- . Shop URL http://www.dx.com/p/1-8w-polysilicon-solar-panel-black-394260 Why this panel ? its a Polysilicon Solar Panel. Easy to connect This epoxy coated for toughness. On the back of the panel are two (thin) solderable terminals, with marked polarity. (While you can solder directly to the terminals, be sure to stress-relieve the connections, e.g., with a blob of epoxy over your wires.) .This guy throw a nice little 90 mA, to 120mA . That is tiny power to be harvested with a super cap . Where to Use 'The circuit ' well there are couple of use cases viz smaller controllers that need 'small power'...