As you mentioned about Hampshire's dimmed Libras, I struggle to see why they don't take a leaf out of Surrey highways book (maintained by milestone inf) and retrofit their stock of Libras.
From discussion with Surrey CC, the retrofits cost less than £80 per unit, including a new node, and phillips electronic gear.
With Hampshire having 100,000 Libras in service, they would be able to achieve a good bulk deal even if they need both sizes.
DW Windsor I'm sure would be able to supply Hampshire over a period of 2-3 years.
The LED retrofits according to Surrey have had no failures and they have about 60,000 installed now.
Hampshire wouldn't even need to replace the node, just plug and play. They may need to re-calibrate the node that's all.
The retrofits use 15W of power versus the 55W PL lamps - I understand Hampshire don't operate their lights at full output.
It has to be said due to the nature of the Libra lantern installation would be less than a minute rather than perhaps 10 for a new lantern.
I've weighed up Pros & Cons for each.
Pros.
1. Would be much cheaper than installing even the cheapest purpose built LED
2. Much quicker to install
3. Less waste to dispose of
4. Better light control
5. Much less energy consumed
6. No need for re-lamps
7. Faster payback (within 2-3 years versus 5+ for other options)
8. Better dimming than with PL - no flickering
9. Equipment gets a 'second' life - resourceful as the lights are meant to last for 25 years.
Cons
1. Premature failure by heat issues
2. Water ingress from 12 year old fixtures is more likely
3. The hardware is obsolete so if a lantern had a smashed bowl this would likely cause the LEDs to fail.
4. Issues may surround around light spread and glare - a decrease in light quality
Overall I feel like the pros outweigh the cons by a long way.
In terms of the Arcs and Iridiums i'd replace them in 2025 time - time for one more re-lamp. The Arcs I'd replace for dw Windsors Kirium eco and the Irdiums the Kirium pros.
Here are 2 photos which show what Surrey have done.
https://drive.google.com/file/d/13dWrl3 ... share_linkhttps://drive.google.com/file/d/1PPfLtJ ... share_linkI await for your views
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