Easy DIY Solar Lighting
(Page 5 of 5)
April/May 2007
By Charles Higginson
Two sources for used equipment are Home Power magazine (under “magazine,” click “marketplace”) and Oasis Montana. The latter also posts worksheets to calculate electrical loads, power requirements and more.
RELATED CONTENT
Want to know how to build your own photovoltaic system, how to construct a solar water pump, or eve...
It’s not every day that you get a chance to tour a green home. Well, here’s your opportunity! Every...
A string of new solar manufacturing plants are scheduled to open within the next few years....
Build a bicycle generator with a bicycle, a battery, and an automobile alternator, and you can prod...
Learn how to generate power with a bicycle, just like actor and environmentalist Ed Begley, Jr. doe...
You also could save about $20 by building your own panel mounts from scratch. And you could replace the safety disconnect unit with fuses in a simple in-line fuse block, saving perhaps $25. Don’t be tempted to omit this protective component altogether.
How Solar Power Works
Photovoltaic (PV) panels convert light energy to electrical energy. In a nutshell — keeping in mind there’s a lot more to modern PV than this — here’s what happens: PV takes advantage of the different characteristics of silicon crystals with different impurities. Pure silicon is not electrically active, because its atoms are locked into a solid crystal structure. There are no “spare” electrons running around, and no spots “seeking” electrons. But certain impurities added to silicon create crystal with a slight tendency to lose electrons, and other impurities create crystal with a slight tendency to attract electrons. When the two kinds of silicon are placed close together and exposed to sunlight, photons (particles of light) knock electrons loose on the “losing” side. These electrons travel across the junction to the “attracting” side. That’s an electrical current.
Light-emitting diodes (LEDs) are made of similar materials and take advantage of the same physical principles, but in reverse. Powering LEDs with a PV panel is satisfyingly symmetrical: photons in, electrons out; electrons in, photons out.
Associate Editor Charles Higginson has not had this much fun since he rebuilt the manual transmission of an old Volvo station wagon.
Page:
<< Previous 1 |
2 |
3 |
4 | 5 |