Hi Paul,

> And only recently have we the switching technology (to convert to
> higher frequency AC and back) to manage HV DC distribution to some
> advantage (less radiation losses - depends also on what your religious
> beliefs are about the danger of fields).
>
>   I think they're using DC SWER distribution somewhere are they not?

Here are a few links to the Cahora Bassa project and other HVDC transmission.

   http://www.mg.co.za/mg/news/96dec1/20dec-bizcahora.html

   http://www.ev.siemens.de/uk/html/b1232.htm

I think it is the longest DC transmission line in the world at 875 miles
(1400 km)

I think it has just recently come back on line after lying idle
for the duration of the Mozambiquan civil war (10+ years)  There
is some acrimony about exactly how much Escom (south african electricity
supply commission) should be paying for the electricity as they still
have a surplus and have also put up money to get the system back on line.

Cheers
--
Kalle Pihlajasaari   kalle@ip.co.za   http://www.ip.co.za/ip
Interface Products   P O Box 15775, DOORNFONTEIN, 2028, South Africa
+ 27 (11) 402-7750   Fax: 402-7751    http://www.ip.co.za/people/kalle

DonTronics, Silicon Studio and Wirz Electronics uP Product Dealer