In February 2020, ScotRail announced plans to convert the remaining class 314 unit, 314209, to be powered by on-board hydrogen fuel cells. The initiative is intended to study the feasibility of using hydrogen to fuel trains, as part of ScotRail's commitment to end its use of diesel fuel for traction by 2035.

In September 2020, it was announced that the demonstrator would appear at the COP26 Climate Change Summit, to be held in Glasgow during November 2021. The unit was to operate special services for the benefit of visiting delegates. In advance of the summit the unit was reclassified into the alternative-fuels class number range and renumbered 614209.

An acknowledged limitation of the Class 614 demonstrator is that it can only carry 80kg of hydrogen, pressurised at 350bar. This is sufficient for short-distance operation as a prototype, but storage capacity will need to be significantly increased for normal passenger service to be feasible. The project team claim that it will be possible to achieve this increase by installing additional storage tanks within the vehicles – a necessity as the UK's standard loading gauge does not allow enough space for roof-mounted tanks.