@Areba, energy saving bulbs are great, esp the new generation ones. I stick to philips. I'll give an example. In the last power rationing, my 2kva ( 24 volts ) design invertor would run ES 10pcs 10 watt and 3 pcs 22watt bulbs at 4 hour tests, all at one go. the small apt looked lit like a stadium and the neighbors would " borrow " a connection for one ES bulb. When testing completed, I'd run my 21inc Sony TV and DSTV decoder for 4 hrs with 3 bulbs. The system was risky as I did not have time to design an overload trip. Times have changed, even a basic ups has builtin checks. Here's the interesting part that got me started then : light and DC oscillation. my first test was using a 6volt bike battery powering 2 mosfets and a 21watt ES bulb. Blindingly bright....  Now it is so much easier. (  "electricity is dangeriuos disclaimer" )