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Dave Plowman (News) Dave Plowman (News) is offline
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Default Dim fluorescent tube

In article ,
Johny B Good wrote:
They are 10 times as efficient as an incandescant.


That explains your misconception then.


Ballast fluorescents are 4 times as efficient, and
electronic fluorescents are 5 times as efficient.


That looks pretty close to the truth of the matter. However, The
reality is that inductively ballasted tubes are a quite few percent
more efficient than even the best CFLs (they don't need a mercury
amalgam to optimize for the higher running temperatures of CFLs at a
slight reduction of efficiency compared to the lower temperature
conditions that normally apply to linear tubes).


When you equalise the benefit of HF electronic ballasting in a linear
fitting to that of a modern CFL, the improvement in luminous efficacy
is even greater.


As things stand, there isn't anything more efficient than an
electronically ballasted linear tube for GLS.


The other thing is to compare like for like. LEDs tend to have a pretty
poor spectrum - and the better that is the lower the efficiency.

Of course if all you're doing is illuminating a corridor it probably
doesn't much matter. But to many it will for, say, lighting a living room.

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Dave Plowman London SW
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