A 100W equv CFL bulb uses about 23W, has 12K hours est life and costs about 6 bucks.
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Apart from the reality that CFLs blow up after 2 to 4 months. Once you are required to use them by "law" (as we are in Australia) then there is no need for the manufacturers or importers to sell you quality product as it becomes an "evil monopoly" and you don't have any choice. So quality drops through the floor. You guys will find out soon enough.
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incandescent bulb: 12000*100W= 1200KWHX.075= $90 + 12*.15= $91.80.
CFL bulb: 12000*23W= 276KWH*.075=$20.70+~$6~=20.70.
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That looks good on paper, until you factor in that 12000 hours of CFL will require 10 more more CFLs (based on my own findings anyway). Also, when they blow up it is usually the HV electrolytic capacitor, that spews really toxic fumes through the whole house.
Also factor in the time and hassle of replacing them and the trips to the store, and if you value environmental concerns then factor in the nasty manufacturing of PCBs, capacitors, mercury, fluorescent materials for 10 CFLs compared to the manufacturing of 1 or 2 glass and tungsten bulbs...
Also domestic electricity is maybe 8% of the national usage as 92% is used by commercial and industry, and out of that the lighting uses only a tiny percentage of your domestic power as 90% goes to heating, cooking, hotwater, and appliances. So it's a crock, pure and simple.
However there is SOME good news. Once they make the incandescents unsellable in the retail outlets you can pick up cases of them real cheap, maybe even free. They should store ok.