I have started gathering materials for the project. I am contacting various manufacturers to get different lights ranging from fluorescent 12 volt lamps to LED replacement bulbs for normal lamps to CFL energy efficient replacement bulbs.

I have a few 12 volt 6Ah batteries that will be used in this project. That should be 72 Watt hours. So, theoretically, based on the battery rating, I should be able to run a 12 Watt lamp for 6 hours or two lamps for three hours on a full charge. Now, again a theory here, if I use an 18 Watt solar panel, running all day in the winter, I should get about ten hours of sunlight. This should be sufficient to keep the battery charged. Cloudy days will change the amount of energy available.

Let's assume 50% sunlight for those ten hours then we have about 90 Watt hours to use up at night.

An average energy efficient CFL replacement bulb is rated for about 13 Watts usage and gives out light equivalent to a 60 Watt incandescent lamp. Add loss for an inverter and that brings us up to about 15 Watts per hour. This should still give us about 6 hours of light on a single battery, solar panel, inverter and lamp. Again, all in theory. The tests results will show how close I am.