How do underground cable options compare with overhead lines?
16.1 Stirling Before Pylons Briefing No. 10 gives Europacables answers to key “FAQ”, which can be seen at http://www.stirlingbeforepylons.org Europacables give examples, as at 2006, and cite recent independent academic studies, to show that continental cost ratios for 380/400 kV “can be as low as 2 to 5 times”. 16.2 Firm costs of underground cables (UGC) compared with overhead lines (OHL) depend not only on terrain and routes, but also on required capacity and associated works such as transformers and reactive compensation. The whole project cost is more than the cost of the line alone. 16.3 Recent communications with industry suggest a rough guide for 400 kV line capital costs of about 0.5 million per km double-circuit OHL with total capacity over 4,000 MVA (to take a maximum of around 4,000 MW). To match that capacity with UGC, 4 cables per phase would be required, with a cost in UK of about 10 million per km, a ratio of about 20. The 5.7 km of 4 cables/phase 400 kV line buried in Yo
