Electric trains (ET) and hydrogen trains (HT) are considered zero emission at the point of use. True emissions are dependent upon non-tailpipe sources, primarily in energy production. We present UK carbon dioxide (CO₂) operating emission model outputs for conventionally fuelled trains (CFT), ETs and HTs between 2017 and 2050 under four National Grid electricity generation scenarios.

Comparing four service categories (urban, regional, intercity and high speed) to private conventionally fuelled vehicles (CFV) and electric vehicles considering average distance travelled per trip under different passenger capacity levels (125%, 100%, 75%, 50% and 25%).

Results indicate by 2050 at 100% capacity CFTs produce a fifth of the emissions of CFVs per kilometre per person. Under two degree generation scenario, by 2050 ETs produced 14 times and HTs produced five times less emissions than CFTs. Policymakers should encourage shifts away from private vehicles to public transport powered by low carbon electricity.

电动火车（ET）和氢火车（HT）在使用时被视为零排放。真正的排放取决于非尾气排放源，主要是在能源生产中。我们介绍了在四种国家电网发电情景下，2017年至2050年之间常规燃料火车（CFT），ET和HT的英国二氧化碳（CO ₂）运行排放模型输出。

将四种服务类别（城市，区域，城市间和高速）与私人常规燃料汽车（CFV）和电动汽车进行比较，并考虑不同载客量水平（125％，100％，75％，50％和25）下每次旅行的平均距离％）。

结果表明，到2050年，容量为100％的CFT将产生每人每公里CFV排放量的五分之一。在两度发电的情景下，到2050年，ET的排放量是CFT的14倍，而HT的排放量是CFT的五倍。政策制定者应鼓励从由低碳电力驱动的私人车辆向公共交通的转变。