Design Details

The first design of the limited energy solar powered lighting system consisted of a solar photovoltaic panel, a battery to store the electrical energy, a charge controller to monitor and control the charging and discharging of the battery, an inverter to change the 12 volt direct current to 115 volt alternating current (standard house power), a shock hazard protection device (GFI), and 115 volt compact fluorescent lamps.

The system as listed above seemed too complex for the simple systems needed for just a few lights.  I was talking with a major lamp manufacturer when during the conversation he pointed me toward a major simplification.  The manufacturers of compact fluorescent lamps were producing lamps that operated on 12 volts DC.  This meant that the inverter was no longer needed which allowed the elimination of the GFI (ground fault interrupter) as there is no shock hazard from 12 volts DC. 

Not only did this simplify the system but it made a significant increase in the efficiency of the system.  The end result was that the lights could be operated for a longer time for a given battery size.