In a small photovoltaic system is absolute necessarily to use 12 V DC bulbs (CFL or LED), due to unjustified losses of energy in the case of using a power inverter 12V DC to AC 110V or 220V.
If you want to use your PV system for anything other than lighting, e.g.. phone charger, cd player, LCD TV, etc you will need a power inverter (true-sine wave or modified-sine wave).
Also these bulbs are ideal if you are working away from a mains electricity supply, they can be connected to any suitable 12 volt battery even your car battery.
I bought this CFL lamp at 11 USD on ebay, it was specified as having 18 watts, but after measurements proved that has only 8-9 watts.
12v DC CFL bulb
|Voltage||12 V (Volts)|
|Current||DC (direct current)|
|Color temperature||6400K (cool white)|
|Life span||8000 hours|
|Measured current||660 mAh (0.66A)|