This instructable will explain how to create a solar powered calculator , experimenting with LED's to produce voltage , build a solar cell using LED's and how to power devices with it.
Step 1: How Does It Work?
The LEDs will be sensitive to the light which has the wavelength equal to it or lesser than it.
When a LED detects light it produces a voltage and this voltage we are going to use to power our clock.
I started experimenting with LED's of different colours and here are my results:
BRIGHT LIGHT AMBIENT
Red LED - 1.3v Red LED - 0.007v
Green LED - 1.4v Green LED - 0.001v
Blue LED - 0.2v Blue LED - 0v
IR LED - 0.1v IR LED - 0.01v
Yellow LED - 1.2v Yellow LED - 0.001v
White LED - 0.003v Whit LED - 0v
From the experiments it is clear that Red ,Green and yellow LED's produce the most voltage so we are going to use one of these three colors.
Step 2: Parts & Tools
~ 10 x LED's (Red , Green , Yellow) - Sparkfun.com
~ A Clock - General Store
~ Some Wires - Local Electronic Store
~ Soldering Iron - Sparkfun .com
~ Solder Wire - Sparkfun.com
~ Screwdriver (Optional) - Sparkfun.com