Several members have made comments recently about the long term future of SON.
I think SON is gradually on the way out.I think the second generation of the Iridium should have been lamped as a MH or Cosmo only lantern, where as the original version would have still been SON, but should be pulled from the catalogue to encourage councils to use the Iridum2.However, this fact obtained from the ILP meeting earlier this year should be taken into account.
Well I have just got back from the ILP Midland Meeting held at SAPA Pole Products.
In the end apart from Simon C, I was the only other "enthusiast" there, all the other attendees were from the trade.
Overall it was a fascinating day with lots of technical snippets gleaned.
This next statement will come as a surprise. Both Philips and Zodion state that 48% of all installed luminaries by number (not wattage) are SOX! SON is 43% by number and the rest are "white light". It seems SOX is not quite as dead as we all thought, I would have thought the number would be half of that. It just goes to show how widespread SOX still is in residential installations.
That means only 9% of the lighting stock is white light - mercury, MH, fluorescent and LED. Now whilst this proportion is bound to rise as CFL and LED become more popular especially due to the PFIs, main road stock is still likely to be predominately SON. For instance whilst some MH is being installed for main roads as part of the Surrey and South Coast PFIs, SON is still also being used especially for the latter.
Whilst the efficiencies of SON and CosmoPolis are broadly similar, the former has cheaper lamps and control gear. Therefore SON lanterns are cheaper. In the present economic situation, price still rules, and for main road lanterns the differential is significant.
Whilst CFL (and the popularity of this is due to low running costs and cheaper lamps/lanterns than SON - dimming of CFL overcomes the theoretical shorter lamp lifetime) and LED (and to a lesser extent CosmoPolis) are likely to oust SON in wattages below 70W and perhaps up to 100W, for the larger wattages, SON is likely to remain supreme - until LED raises its efficiency and its reliability is proven - perhaps 5 years away. It could be a decade after that before LED really gets a market hold. It has taken SON more than 20 years to get where it is now.
Given all of this, manufacturers are not going to phase out SON lamps or SON lanterns while they form such a significant part of their business.