Well, you have been continously hearing about energy saving through CFLs and I am sure you must have tried many typs already, and may have your own views and judgement about the way the CFL performed for you.
I have been closely observing and experimenting with CFL since past 2-3 years. This is what I found:
1) Havell CFL bulbs are the best. They give good colour temperature l aight that is also termed as "cool daylight" in lay man's language.
2) Philips comes next best. The performance of the Tornado series is very good.
3) All other brands are a waste of money. Wipro is the worst, it did not even last for a year and its light quality was lost withon 3-4 months.
Why CFL?
CFL stands for Compact Flourosent Light. Making it clear that you can use it as an equivalent to your large flourescent tube light.
CFLs use very less energy and give higher light output. But this light does not spread to larger areas as in case of a tubelight. Therefore to light a big room, instead of one tubelight you may need two or more CFLs.
CFLs have a light output that is very near to daylight, so it is good in rendering the original colours in room as they appeared in daylight.
CFLs save 70% to 80% in your electricity bill.
How to choose a CFL bulb?
1) Light sources are measured in lumens. CFLs work more efficiently than incandescent bulbs and therefore use less wattage to deliver an equivalent amount of lumens. Therefore it is better to compare lumens rather than wattage.
2) A 100-watt incandescent bulb produces 1700-1800 lumens (a measure of total light output), so just look for CFLs with a similar lumen output. Being more efficient than incandescent lights, these will consume much less than 100 watts.
3) You will also want to pay attention to the colour of the CFLs that you buy. It will usually be printed on the packaging as a colour temperature, a number with a K (for kelvin) after it. If you want it to look like an incandescent light, then somewhere around 2700-3000K should be about right. This is quite "red" or "warm" in colour. Higher numbers are more "blue" or "cold" looking and many people don't like that.
4) Stay away from Wipro and other unlnown brands.
5) Only buy Hawells or Philips.
6) Replace the incandescent bulb with a higher rating CFL bulb. For example if you want to replace the 60 watt incandescent bulb (which is equivalent to 15 w CFL), replace it with 18 w or 20 w CFL that is equivalent of 75w or 100 w incandescent bulb.
7) If you will replace 60w incandescent bulb with 15w CFL bulb, it will have wattage same as 60w incandescent bulb but will appear to have weak light. Therefore always use higher equivalents. People make this mistake often, they do not replace with higher rating.
To help you, here is a general guideline to chosse a CFL bulb:
5w CFL can be used for 25w incandescent bulb
9w CFL can be used for 40w incandescent bulb
18w CFL can be used for 60w incndescent bulb
23 w CFL can be used for 100w incandescent bulb
Hope, this helps you in buying the right CFL.
If your room is large, you will need more than one bulb. But remember that CFL bullbs require warm up time of 2 to 4 minutes to reach to their correct output.