More or Less on Radio 4.
There is only a 3:1 ratio in brightness: you need a 33W new bulb to replace a 100W old bulb. That's not what the boxes say.
The life of 10 years assumes the bulb is off for over 85% of the time, and is an average: 50% will have failed after 10,000 hours (416 days if always on) of use.
The 80% energy saving is a falsehood: it includes heat generation that is compensated for by heating reductions.
There is only a 3:1 ratio in brightness: you need a 33W new bulb to replace a 100W old bulb. That's not what the boxes say.
The life of 10 years assumes the bulb is off for over 85% of the time, and is an average: 50% will have failed after 10,000 hours (416 days if always on) of use.
The 80% energy saving is a falsehood: it includes heat generation that is compensated for by heating reductions.
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