COMPACT fluorescent light bulbs (CFL) used at least 60% less energy than old-fashioned incandescent light bulbs and lasted 10,000 hours. The newer Light Emitting Diode lights (LED) use up to 90% less energy than CFLs and are expected to last up to 25,000 hrs. Should you make the change?
For certain, any new bulbs you buy should be LEDs rather than CFLs and, if you have any old-style incandescent bulbs still in the house, swap them for LEDs. They come in various shades from bright white to soft pink, and some are compatible with dimmer switches (check the packaging). They don’t take time to reach maximum light intensity, can work in colder rooms or outside, and are all far more cost-effective. They’ll be with you for a long time, so check the shape and size of bulb you want for each fitting before going out to buy, and remember they come in many more shapes and sizes than the CFLs, so you now have more choice.
Should you replace working CFL bulbs? LED bulbs are relatively expensive to purchase and energy-consuming to make, so probably the answer is to wait until a CFL bulb gives out in your house. If it is in a main room with frequent use, replace it directly with LED; if in a room used less often, then see whether you can shuffle things around and put the new LED into a light fitting which is used more frequently.
Colour rendering index (CRI) varies between brands. Check that it is in the high 80s, and not less than 80. Hopefully the packaging will give the equivalent to old incandescent bulbs but, if not, then an old 100W incandescent is an 18W LED giving 1300+ lumens.
If you just want a replacement bulb that works with a light switch, then keep away from ‘SMART’ LEDs: these are internet connected bulbs. Finally, keep the receipt and the packaging somewhere safe, as these are guaranteed for several years.