Some of the ones in Birmingham are... But only usually replaced when the old
ones burn out or get broken (which I fully agree with, no point emitting CO2
driving round and replacing every single one when they still work perfectly
- the don't-replace-old-cars-with-new-cars argument).
Which is a poor argument, as the LCD replacements would start saving
money/power/CO2 straight away and would be fitted to the existing hardware.
Their longer life would reduce the number of "driving arounds" by a factor
of tens within the lifetime of the LED panel. Granted someone will have
to change the coloured filters with transparent ones.
But how long does it take for the improved efficiency of the newer LED
clusters to offset the diesel emissions of the vans, emissions of the
workers who travel to the depot every morning and go home every evening
(probably stuck in traffic jams), plus any other power tools used when
changing the lights..
And add into the mix the fact that they always work on traffic lights in the
daytime (for safety reasons I think) - when driving through Selly Oak, I've
driven past a man up a ladder precariously close to the road edge who's
fixing the lights several times :) So, if you have a man up a ladder doing
the fixing, you have to have someone else watching his back, then you
potentially need temporary traffic control (either with a man with a
lollipop or temporary lights), and the list goes on.
The bulbs in the traffic lights themselves are smaller than you'd think
considering the diameter of the 'light', the front lens does a really good
job of refracting and magnifying the bulb's light. I still think it'd take
months and months and months to recover the CO2 emitted while replacing
every bulb, if not at least a year - when by that time, the bulb may have
quite possibly burnt itself out anyway requiring a simple one- or two-man
swapout instead of a massive operation.
Part of me has just remarked that it can't believe I'm having a discussion
about traffic lights :D
