At the time, BR had intended to enhance the power supply to cater for 12-car Networkers. Tenders were even issued for the necessary works & equipment (substations, cables, etc.) and as well as the platform extensions mentioned elsewhere in this thread, I believe some groundwork had been carried out and some supplies had already been delivered.
This all coincided with the economic downturn in 1992 and BR announced that the project had been cancelled, even though work had already started.