In the 1930s, the English Electric Co. were busy designing and building diesel engines for railways – mostly around the former British colonies, but the impact of the economic depression had Britain’s railways looking for efficiency – especially for use on shunting operations. But English Electric had for some years been at the heart of technology innovation and development and had been trying to persuade the more conservative railway operators to look to the future.
The company developed a diesel-electric version of the classic 0-6-0 steam shunting locomotive, powered by a 6-cylinder diesel – or as the press referred to it an ‘oil-engine’ – to sell the idea to either the LMS, GWR, LNER or Southern railways. The LMS was first out of the blocks and with English Electric as the engine supplier, with Derby constructing the mechanical parts, they embarked on an ambitious project to tap into the benefits of diesel power for shunting work. They were followed by the GWR and Southern Railway, and the latter followed the English Electric power plant path, whilst the GWR had opted for a variety, including Davey Paxman engines.
20 years after the first LMS shunters began to appear in the early 1930s, in 1953, British Railways placed orders for what became the standard shunting locomotive – the 350hp, or Class 08 type. Hundreds of these were built, mainly at Derby, Crewe, Darlington, Doncaster and Horwich Works with a pair of d.c. traction motors driving the wheels, which were linked by coupling rods, exactly as a steam loco would have been. Ultimately, 996 of these 0-6-0 shunters were constructed at the railway works – some were built at English Electric’s works in Preston, and Vulcan Foundry at Newton-Le-Willows (mainly for Netherlands Railways).
At nationalisation in 1948, British Railways inherited a motley collection of 60 of the 0-6-0 diesel shunters – 46 from the LMS, 7 from the GWR, 4 from the LNER and 3 from the Southern. Of these all, bar one had an English Electric 6KT diesel engine and traction motors, and that exception was the 1934 Armstrong Whitworth built loco, with a Paxman engine and a mechanical drive through jackshafts from its single traction motor.
The Harrier HydroShunter project to convert locomotive from diesel to hydrogen traction will take ex BR Class 08 shunter No. 08635 and remove the English Electric engine and generators, to be replaced by a hydrogen fuel cell stack and battery, as a hybrid installation. The project is unique and involves the University of Birmingham, Vanguard Sustainable Transport Solutions, and the Severn Valley Railway.
It’s a brilliant idea, and if successful could pave the way for similar replacements at home and abroad, and whilst passenger trains for commuter services have seen similar projects highlighted, such as the conversion of Class 314 for the “Hydroflex” train, this has perhaps just as wide ranging potential. Following the earlier projects, the traction system being designed by Vanguard at the University of Birmingham, this hybrid system will consist of a hydrogen cylinders, a fuel stack where the electricity is generated and a battery.
The loco was formerly D3802, built at Derby in December 1959, and renumbered in January 1974 and withdrawn from BR service in December 1981. It is currently at the SVR’s Kidderminster diesel depot, and the team of volunteers have removed the diesel engine and generator, and have been busy renovating and overhauling other key components. The SVR had to hire a 100-tonne crane to lift the diesel engine out of the shunter, and the work is now well underway to achieve trials later in 2021.
The new power unit includes pressurised hydrogen stored in cylinders for supplying to the fuel cell stack via a regulating device, oxygen from the atmosphere will then be mixed, and electricity generated and delivered to the loco’s traction motors. The battery will also be charged by the fuel cell stack, to provide energy reserves as and when needed. The existing traction motors, controls and final drive is being retained, with the new equipment fitted to a new sub-frame, which in turn is mounted to the existing engine-generator mounting points.
Of course, with the hydrogen fuel-cell power, emissions are zero compared to the old diesel engine, and it has been suggested that there will be a reduction in maintenance costs of possibly 50%, which if it is successful could see many more similar retrofit projects. Although, whilst we may be at the start of a new era in terms of non-electrified traction, as the fuel cell technology evolves, it may be that larger locomotives could see similar replacements. This might not see huge numbers in countries where expenditure on electrification has been significant, but in other countries, where funds are lower, it could provide opportunities – providing the capital costs are also low.
There are of course some disadvantages to hydrogen as a fuel, mostly in terms of the way it is produced, and its storage – according to one source (https://www.theengineer.co.uk/comment-hydrogen-trains-uk/ ). “Firstly, hydrogen storage is bulky. Even at 350bar, the volume of fuel needed is eight times that of Diesel.” The author goes on to state that that could be a problem for long haul freight services, and would be unsuitable for high-speed rail, on account of the amount of electrical energy required, and the losses developed in the power unit. But, it is being considered for some types of rail passenger service, in order to remove the dependence in rural area on diesel multiple units.
It will be fascinating to see this project completed, and what might develop over the next few years, and whether the technology does play a part in maintaining the railway’s place as a sustainable mode of transport.