Thoughts on use of hydrogen to power railway trains

Nearly all energy generated eventually ends as a thermal release to atmosphere. The combination of all these sources of heat is warming the planet amid concerns over the consequences of this global warming. Most fuels are hydrocarbons and on combustion release carbon dioxide. This is a greenhouse gas and amplifies the effects of this warming, as does methane, a major constituent of natural gas, the prime gas fuel. The combustion of hydrocarbons can produce other pollutants such as CO, particulates and NOx which are injurious to health. One option for gas fuel users is to replace natural gas with hydrogen as hydrogen does not contain carbon thus eliminating many undesirable emissions. Here, the use of hydrogen at pressure, as a fuel for railway trains is examined and the consequences of its use presented. In the UK, a large amount of hydrogen will be needed if this is to be the sole gas fuel, but this is yet to be determined. However, there is a special application to which hydrogen can contribute – “hybrid” trains. These are essentially electricity-powered trains which use hydrogen as a fuel for low-speed application such as in marshalling yards or under cover in terminus stations where exhaust pollutants can accumulate. In addition, local low-speed trains, where traffic density is insufficient to justify electrification, can use fuel hydrogen. A statement of fixed plant costs to satisfy this potential hydrogen market as well as fuel running costs are included.