The Class 614 (not my picture) It is a 3 car HMU (Hydrogen Multiple Unit) Converted from a class 314 (314209) for display at COP26 I have seen it with my own eyes before back in June (my picture below) at the Bo’ness and kinneil railway where it was being worked on at Bo’ness TMD
There's a few old EMUs being converted into Hydrogen Mules at the moment - no plans for them to carry passengers, purely for R&D