LONDON UNDERGROUND intends to procure a new fleet of battery locomotives for its engineering trains, with a view to replacing the current fleet in the 2020s.
The 29-strong fleet is undergoing life extension works, with 22 locos treated by the end of March; all will be completed by August 2019.
The life extension work will extend their lives until 2026 and make them compatible with the 750V power supply that will be used on the sub-surface lines following the Four Lines Modernisation programme; the locos were not designed to operate at this voltage.
However, LU says a further limit is that the battery locos can only accommodate two types of modern signalling system. Following the upgrade of the Piccadilly Line, due for completion in 2026, the LU network will include four modern and two legacy types of signalling system, creating difficulties in delivering elements of LU’s track renewal programme.