Derby's Street Lighting PFI Contract - Alfreton Road, City Centre

Although the majority of Alfreton Road was relit in September 2009, the section within the 60 mph limit (but before the railway bridge) did not undergo relighting until November 2011. The following photographs detail this later replacement work, and were taken on Sunday, 27th November 2011.

All but one of the outgoing installations along this section of the road supported 135 Watt SOX lanterns. This integrally-geared Thorn Alpha 4 was attached to a Stewart & Lloyd tubular steel column that was located just within the 60 mph limit. The illuminated speed limit signs were also undergoing replacement as part of this scheme, with the outgoing signpost supporting twin Signature Exlite LA signlight units. Its replacement supported twin Simmonsigns LUA signlights.

This Alpha 4 sported a somewhat grubby bowl.

The replacement lanterns are the 'large' (SGS 254) version of the Iridium, and each runs a single 150 Watt SON-T lamp.

Am I seeing double for the next installation? No, both the old and new columns here supported Iridiums, although the outgoing column (a replacement during the PFI era) supports a 'medium' (SGS 253) version, and was slightly shorter at 10 m, in comparison to the non-standard 11 m columns used as replacements.

We return to 135 Watt SOX for the rest of the redundant columns. A remotely-geared Alpha 4 was installed here.

This example's bowl looked a lot cleaner than the previous Alpha 4's bowl did.

Both the optic and the inside of the Iridium is sealed to IP66; therefore, no noticeable signs of ingress should ever be present in the bowls of the new lanterns - that's the theory, anyway!

An integrally-geared Philips MA 50 was next.

The lantern's GRP canopy was beginning to show its age.

Although the Iridium canopies are also constructed of GRP, they are supposedly more resistant to degradation thanks to being treated with a special substance that maintains the smooth appearance of the material; again, time will be the decider here.

Another MA 50 followed; viewing the installations from the opposite side of the road clearly demonstrates the difference in size between both lanterns.

Another remotely-geared Alpha 4 was fitted to the final outgoing column on this scheme.

The overall structure of this version of the Alpha 4 is identical to the 90 Watt SOX version - the additional space within the lamp area, when the shorter lamp is fitted, allows the control gear to be accommodated.

The new lighting was not yet operational at the time of photographing.

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