How to Make a Solar Power Generator for Less Than
$300
Solar Power
The principle of photovoltaic power (converting light into electricity was
discovered in 1836
when it was found that sunlight striking a surface emits electrons ? With
positive and negative poles a DC current could be obtained ? With the
development of solar cells and solid state electronics, solar power generators
have become reliable alternatives to the power grid ? These can be stand-alone
systems, such as are currently in use to power entire hospitals in Zaire and
remote archeological digs, or they can be portable such as the one illustrated
here
Using parts easily available from your local stores, you can make a small solar
power generator for $250 to $300
Great for power failures and life outside the power grid.
Power your computer, modem, vcr, tv, cameras, lights, or DC appliances
anywhere you go
Use in cabins, boats, tents, archaeological digs, or while travelling
throughout the third world
Have one in the office store room in case of power failures in your highrise ?
I keep mine in my bedroom where it powers my cd player, turntable, lights,
modem, laptop, and (ahem) a back massager ? I run a line out the window to an
8" x 24" panel on the roof
1) Buy yourself a small solar panel
For about
$100
you should be able to get one rated at 12 volts or better (look for 16 volts)
at an RV or marine supplies store
2) Buy yourself a marine (12V) battery (lead/acid ~ holds deep cycle 95 to 102
Amps for long periods of use ? Two ports for cigarette lighter inverters,
analog window shows charge level, AC plug out to charge battery when AC is
available ? Push-button fuse) You need the deep cycle battery for continuous
use ? The kind in your car is a cranking battery--just for starting an engine
Look for bargains, it should cost about
$50-60
3.
Get a battery box to put it in for
$10
(This is good for covering up the exposed terminals in case there are children
about If you going to install the system in a pump shed, cabin, or boat, skip
this)
3) Buy a 12 volt DC meter
Radio Shack has them for about
$25
4) Buy a DC input
I like the triple inlet model which you can find at a car parts store in the
cigarette lighter parts section for about
$10
This is enough to power DC appliances, and there are many commercially
available, like fans, one-pint water boilers, lights, hair dryers, baby bottle
warmers, and vacuum cleaners ? Many cassette players, answering machines, and
other electrical appliances are DC already and with the right cable will run
straight off the box
5) But if you want to run AC appliances, you will have to invest in an inverter
? This will convert the stored DC power in the battery into AC power for most
of your household appliances
I bought a 115 volt 140 watt inverter made by Power-to-Go at Pep Boys for
$50
More powerful inverters are available by mail ? Count up the number of watts
you'll be using (eg, a small color television(=60 watts) with a VCR(=22 watts),
you'll need 82 watts)
6) Use a drill to attach the meter and DC input to the top of the box
7) Use insulated wire to attach the meter to the wingnut terminals on the
battery ? Connect the negative (-) pole first ? Only handle one wire at a time
? Connect the DC inlet to the battery in the same way ? Connect the solar panel
to the battery in the same way
8) Close the lid (I use a bungee cord to keep it tight) Put the solar panel in the sun ? It takes 5-8 hours to charge a dead battery; 1-3 hours to top off a weak one ? It will run radios, fans, and small wattage lights all night, or give you about 5 hours of continuous use at 115 volt AC, or about an hour boiling water ? This system may be added on to with larger panels, inverters, and batteries
Options: A pop-up circuit breaker may be added between the positive treminal and the volt meter ? Some of you will want an ampmeter as well ? The panels I recommend have built-in bypass diodes, but I recommend charge controllers for people who have panels without diodes ? Another option is a voltage regulator, which is not necessary for a system this small, but a larger system would require one