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Don Klipstein

In article .com,
wrote:
Don Klipstein wrote:

Don is a lighting expert with a very informative and detailed site
last time I looked. However readers should bear in mind that tube
types, starting types, costs, common practices and terminology are all
different here in UK to the US.

Also I think somehting was missed in your calculations of switch off
break even time. If keeping the tube on for 20 minutes gains you 20
minutes extra tube life, you have in fact gained absolutely nothing.
The only difference is that 20 minutes of electricity have been
wasted. You wont get a single extra day of service time out of the
tube this way. I dont know why but this is so often overlooked in
these calculations.

Oops, I was only calculating break-even points in whether cost of
operating the lamp is increased or decreased, without regard to
considering leaving-the-lamp-on causes some of the lamp's life to be
wasted in addition to the electricity being wasted.

I expect that adding consideration of wasting lamp operating life will
change break-even-time calculations and make break-even times shorter.

I expect this correction will only make break-even times slightly
shorter if electricity consumption during the life of the lamp (bulb)
costs a lot more than the lamp (bulb) does, which is often the case.
With lower wattage lamps, lamp cost becomes a more significant fraction
of the total cost, so this correction gets less minor.

- Don Klipstein )