Hello I have seen pics on this site of UK rural distribution lines. I think the rural distribution network first started in the 1940s did the poles and pole mounted transformers always take the same apperence since then? Have the voltages always been 11kV and 33kV since then? What was the position with distribution before the nationalisation of the electricity industry (i think in 1948) where the many different voltages and designs of poles/transformers in use? If so are any of these lines still in use? Also an intresting question for you-does anyone know where and when the first HV power line in the UK was built? Luke
Hi Luke, Welcome to ECN, mate!. I take it that you are referring to the pics posted by Pauluk. I really can't comment either being in New Zealand, but no doubt Paul will add to this thread sooner or later. Good topic though.
Re: UK rural distribution#144711 01/10/0610:01 AM01/10/0610:01 AM
Rural distribution goes back to before the 1940s, although I have to confess that I couldn't tell you the first HV line installed.
In the earliest days of mains electricity DC generators were used, which of necessity had to be located very close to the areas they served due to power being generated at the same voltage at which it was utilized. That's why the old districts of some cities still had DC power as late as the 1950s, as they were the earliest areas to be wired for mains.
HV transmission lines only became practical with AC generation. I would think that the earliest HV lines were what would today be regarded as short haul -- Just distributing AC at "low" HV voltages (3.3kV etc.) around a city. The more extensive network which eventually became the National Grid grew up gradually from that.
I don't doubt that the very early poles and xfmrs looked somewhat different, although the U.K. seems to have settled on common designs from a relatively early time: Horizontally aligned cables on cross arms for 11kV etc. Some of the early equipment would have been different by necessity though. Back in the 1920s and before, some areas were running on 25Hz AC instead of 50, which would mean much larger transformers for a given power.
Re: UK rural distribution#144712 01/10/0610:03 AM01/10/0610:03 AM
Intresting. I see paul you mentioned 6.6kV distribution. Talking of this does anyone know what 6.6kV overhead distribution looks like-does it use the same poles/crossarms as 11kV or can you tell a 6.6kV line apart from an 11KV?
Re: UK rural distribution#144714 01/12/0606:05 AM01/12/0606:05 AM
Thanks to Alan Belson for the following scans of 1920s lines and equipment.
Attached pic of 1926 UK 11kv terminal transformer pole. This is the dawn of the 'grid' - before this, individual power stations operated close to consumers, so transmission over long distances was unnecessary.