See https://bathtrams.uk/dft-calls-for-light-rail-proposals-across-the-uk-here-is-the-lrta-light-rail-transit-association-response/ for full article for above image
See also for detailed calculation: https://bathtrams.uk/the-most-energy-efficient-mode-of-public-transport/
See also: https://bathtrams.uk/oslo-effect-comparative-non-tailpipe-emissions-from-various-forms-of-transport/