Colin Rosenstiel wrote:
Surely just for local heating in the depot? we tend to forget nowadays
just how much infrastructure there was for delivering coal to domestic
and business properties until about 40 years ago or less.

No. The Waterloo & City Line predates the national grid (it opened in
1898). Electricity to run the trains was generated by a small power
station in the depot, and coal was delivered there using wagons brought
along the Waterloo mainline and lowered by lift.

U