The following news report about dual powered engines (i.e. electric/diesel) for the South Wales Main Line may be of interest:
http://www.walesonline.co.uk/news/wales ... n-10287160
Is this seriously being proposed?
South Wales Electrification
Re: South Wales Electrification
Don't forget that a good proportion of IEPs would have diesel engines anyway (known as 'bi-mode'). Modifying the 'all electric' order to be bi-mode is under serious consideration.
http://www.railwaycodes.org.uk; railway photos https://www.flickr.com/photos/pdeaves/