Small Scale Solar Energy

Renewable forms of energy fascinate me.  I suppose part of their appeal is that virtually all your cost is up front.  After you make your initial investment, it’s as if you had “free energy.”

Here in the Sunshine State it makes sense to tap into solar power.  I haven’t taken the plunge into a large solar system.  In fact, I’m at the opposite end of the spectrum.  I enjoy experimenting with small scale solar projects to get a feel for their capabilities.

Why do I bother with small scale solar systems?  First of all, they come in handy for any prolonged power outage.  Beyond that, the devices they can power are always useful around the house, on camping trips and even on picnics.

To start up a micro solar system you need just three things:   a solar battery charger, a few rechargeable batteries and devices that run on batteries.

Solar battery chargers:  My solar battery chargers are all the same model:  C. Crane Solar Battery Charger with meter.  It can handle pairs of AAA, AA, C or D rechargeable batteries.  The charger will also accept “Gum” (prismatic) batteries but these aren’t very common.

The meter measures the intensity of the sunlight and gives you an estimate of how long it will take to fully recharge the batteries.    For example, in bright sun it would take about three hours to charge up a pair of AA batteries. 

 I still need to add a solar battery charger that can recharge cell phones.  I want to be sure I can contact the outside world in an emergency.

Rechargeable batteries:  Most of the batteries we use at home are nickel –metal hydride (NiMH) rechargeable batteries.  They come in the same sizes as standard alkaline batteries.  They tend to be more expensive than the nickel-cadmium (NiCd) batteries you find in outdoor solar lights because they have two to three times more capacity.

Battery powered devices:  We use our solar recharged batteries in TV remotes, children’s toys, LED lamps, flashlights and radios.  We even use eight D cell rechargeable batteries to power a portable fan, the O2Cool.  It’s the only battery operated fan that I‘ve found that can effectively cool your whole body.

IKEA produces a useful solar powered LED table lamp called the Sunnan.  You simply snap out the battery pack and leave it in the sun all day.  In the evening you snap the battery pack back into the lamp base and it gives off a comfortable reading light for about two hours.  It was designed to provide enough light so that children could do their homework in parts of the world that don’t have electricity. 

For critical systems like smoke detectors and battery backukp it’s better to use alkaline batteries or lithium batteries.  They have a much slower self discharge rate than all but the most advanced nickel-metal hydride batteries.  That way you’ll have power when you really need it.