Martin Evans wrote:

"A 230V lamp operated at 240V will only achieve 55% of its life"

Precisely. A large proportion of lamps now come from overseas, both
within Europe and the far east but simply marked "240v" - the
filament in a number of cases is absolutely identical to those
utilised on mainland Europe and the UK consumer is non the wiser

And your evidence for that statement is what, given that just about
every other country uses only ES bases...? I.e. a lamp marked 240 V
with a B22 base must be made for the UK market (and Eire, perhaps).

I'm sure that there must be a market for a cheap scr device, maybe
situated in the consumer unit to limit the volts on the lighting
circuits.

An auto-transformer, or a 12V halogen lighting transformer wired as an
auto-tranny is the obvious solution.

What is this obsession with lamp life anyway? GLS lamps are cheap; it's
the electricity that costs. View over-running as a benefit - more
lumens per watt :-)

I know it wasn't your post Andy but "bulbs" are things that sometimes
sprout flowers and nothing to do with electrickery.

Quite right too.

--
Andy