On 30 October, over 150 delegates from the industry and research institutions attended RSSB’s “Intelligent Power Networks to Decarbonise Rail” conference, held at the University of Warwick. This event considered how more energy-efficient, zero-carbon technologies could be developed in response to the former Transport Minister’s challenge to see all diesel only trains off the tracks by 2040.
The conference was a platform to launch two research competitions that offered significant funding for projects to decarbonise the rail industry.
It opened with an overview of the industry’s sustainability initiatives and the background to the competition. This was followed by presentations on innovative traction power projects and industry stakeholders describing their main priorities, to which sixteen companies gave one-minute pitches in response. Information was then provided about the competitions and other funding opportunities.
No diesels after 2040?
Transport accounts for 24 per cent of the UK’s total greenhouse gas emissions. Although UK Rail only accounts for two per cent, and is already a low carbon form of transport, there is significant scope for improvement, particularly in respect of local emissions. Traction alone consumes over 700 million litres of diesel and 3,500 GWh of electricity each year, at a cost of over £500 million. In addition, Network Rail spends £60 million each year on utilities for its non-operational estate.
In February, the then Transport Minister, Jo Johnson, called for diesel-only trains to be off the tracks by 2040. However, his reference to diesel-only trains shows that it is considered acceptable for diesel bi-mode trains to continue operating beyond this date.
Andrew Kluth, RSSB’s lead carbon specialist, explained that, in response to this call, an industry task force had been set up which will soon publish the industry’s response. He explained that the task force aimed to move UK rail to the lowest practicable carbon energy base by 2040, enabling the industry to be world leaders in developing and delivering low-carbon transport solutions for rail.
As part of its work, the task force considered journey types and performance requirements against various traction options as shown in the table.
It concluded that a whole system balance will be required between electrification, where it is cost effective, and new traction technologies such as hydrogen and batteries. Transitional arrangements for these new technologies have to be considered and, where no other options exist, significantly more efficient and cleaner diesel will be needed.
Low carbon trains
Mike Muldoon of Alstom, which already has the world’s first hydrogen train, the iLint, in passenger service, gave the first of three presentations on projects to modify existing rolling stock. The iLint is a hydrogen-hybrid train with a traction battery. As Mike described, “the clever bit was the energy power management system for which the development effort should not be underrated”.
To bring this technology to the UK, Alstom is planning to convert a Class 321 EMU to create a UK-gauge hydrogen train in a partnership with Eversholt Rail.
Mike emphasised that hydrogen trains are “no silver bullet”, but have a potentially useful role on lines for which electrification cannot be justified where they can exceed the performance, but not the range, of a DMU. Although hydrogen trains can easily be refuelled, to make the best use of the required hydrogen supply and production facilities, it is best to operate them as a small fleet.
A significant advantage of hydrogen trains is that they have no harmful emissions, as their only exhaust is water. However, their carbon credentials depended on how hydrogen is produced. Almost all hydrogen is produced by steam reforming, which offers a 45 percent reduction in CO2 compared with diesel. Hydrogen can only be a truly zero-carbon fuel if it is produced by the more expensive electrolysis process using ‘green electricity’, such as wind power.
Kevin Blacktop from the University of Birmingham described the Hydroflex train, which is another UK hydrogen train proposition currently under development. He explained that the University had undertaken much research into hydrogen propulsion and, in 2012, produced the UK’s first hydrogen train. This was a 10¼ inch gauge locomotive powered by a one-kilowatt fuel cell as the University’s entry in the IMechE’s Railway Challenge.
Hydroflex is the subject of an agreement, signed in September at Innotrans, between the University and Porterbrook which will supply a Class 319 for conversion. This will operate on 25kV overhead and 750V DC third-rail and, in self-powered mode, will use a hydrogen fuel cell. Demonstration runs are expected to commence in summer 2019.
Angel Trains is developing the Hydrive. This will be a new hybrid train that will have a diesel engine, traction battery and power management control system and which, as David Bridges explained, will offer significant environmental advantages. These include constantly running the engine at its “sweet spot” to maximise efficiency and reduce emissions, regenerative braking, and the elimination of diesel engine emissions at stations.
The first Hydrive unit will be a converted Chiltern Railways Class 165 unit that is expected to enter service in October 2019.
Challenges and opportunities
To set the scene, representatives from different parts of the industry outlined the challenges that needed to be addressed.
From Freightliner, Paul Smart stressed that rail freight faced keen competition from road haulage and so required any diesel-replacement technology to match diesel’s operational characteristics with no increase in size or weight or reduction in payload.
Network Rail’s Wendi Wheeler noted that there were limited decarbonisation options, as there is currently no viable alternative fuel source to diesel. She also highlighted the need for traction and non-traction energy storage, for which Network Rail could provide land. In addition, she mentioned the scope for savings at major stations, which are massive energy users, including the deployment of modern metering.
Graeme Clark from Siemens Mobility was concerned that rolling stock companies had to invest in the future of a frequently changing, delayed and unstable rail franchising system with no fixed, long term view of rail electrification.
Presentations from Porterbrook, First Group and Virgin Trains all stressed the need to reduce traction fuel consumption. Virgin’s Russell Preece noted how driving style affected fuel consumption, whilst Porterbrook’s Chandra Morbey emphasised the need to reduce embedded carbon by minimising the use of spare parts and materials. From First Group, Martin Ward highlighted the need for energy efficiency at depots and noted that the franchise business-case timeframe – seven years or less – made it difficult to justify the cost of decarbonisation measures.
Herb Castillo explained how HS2’s electricity consumption would eventually be 60 per cent of that required for all current UK rail traction. Hence the company’s aspiration is to have directly connected, renewable, low-carbon traction supplies and technologies to reduce non-traction energy consumption. HS2 is already in discussion with potential electricity suppliers so as to have time to invest in the required facilities before the high-speed line starts operation.
Cases and pitches
In four case studies and sixteen elevator pitches, solutions and expertise were promoted to respond to these challenges.
Riding sunbeams to power the 750V DC rail network was the first case study. Leo Murray of Climate Action, an organisation promoting community-level practical projects to tackle climate change, explained how this initiative builds on the success of the Blackfriars solar bridge and Antwerp’s solar rail tunnel.
He explained how local solar farms, such as a 4MW installation at Cuckmere, could be connected directly to DC rail network sub-stations via DC to DC converters. This was one of seven identified sites that were estimated as being able to supply fifteen percent of the southern DC network’s annual demand of 1.38 TWh.
Solar farms could also power other UK DC traction networks and, possibly the 25kV AC network, for which solar power connection options were being evaluated.
The benefits of an internal combustion engine without a crankshaft were explained by Professor Tony Roskilly from Newcastle University in his presentation on the free-piston engine, in which two connected pistons move in a cylinder with compression chambers at each end. Drive and control are by a linear induction motor at the centre of the cylinder.
This configuration gives an engine that is 60 per cent smaller and 25 per cent lighter than a conventional internal combustion engine with lower friction and heat transfer losses. It also has better thermal efficiency due to an ability to control the piston velocity profile as well as being easily modified to use alternative fuels as compression ratios and valve timing are software controlled.
This concept, which was first proposed in the 1940s, has now become potentially viable with the availability of modern, microprocessor control technology. The University of Newcastle has been working on it for some years and has a £200,000 research grant to use it as a 25kW range-extender for hybrid electric vehicles.
In another case study, Professor Philip Mawby of the University of Warwick explained how Power Electronics UK was using Silicon Carbide (SiC) for lower cost, higher efficiency power electrical applications. His presentation showed that the use of SiC devices is currently saving 10 million tonnes of CO2, the equivalent of eight coal-fired power stations or 1.7 million cars being taken off the road.
The advanced multi-fuel technology offered by G-volution enables diesel engines to use lower carbon alternative fuels. Shimon Shapiro explained how his company’s technology enables engines to use a diesel-LNG combination of fuels, giving a carbon reduction of 25-70% and a fuel cost saving of 33-44% (according to the G-volution feasibility study). Other fuel combinations, including diesel-bio-LPG, and diesel-bio-hydrogen, can offer carbon savings of 10-45% per cent, and fuel cost savings of 25-50%.
These case studies were followed by short, one-minute elevator pitches from the following organisations:
- University of Nottingham – one of the world’s biggest power electronics research groups;
- Loughborough University – rail vehicle modelling and simulation, control system development;
- Manchester Metropolitan University – power systems, energy storage and forecasting;
- Warwick Manufacturing Group – advanced propulsion and lightweighting, technology transfer from automotive to rail sectors;
- University of Chester – carbon capture and utilisation, fuel cell technology, energy control systems;
- University of Birmingham – power system modelling, including large scale power grid simulation;
- University of Sheffield – mechanical expertise including overhead line dynamics, material fatigue and wear at train-infrastructure interface, optimisation of rail operation with energy supply and storage;
- University of London, SellickRail, Dynamic Boosting Systems and Gyrotricity – patented electric flywheel;
- Hasler Rail/Sario – accurate measurement of AC, DC or fossil fuel energy consumption;
- Ultra Light Rail Partners – ultra light rail solutions including compressed air and cryogenic engines;
- Unipart Rail – product development for global rail markets;
- Perpetuum – expertise in wheelset life extension and maintenance optimisation;
- FTI Communication Systems – telecommunications networks;
- Clean Power Hydrogen – advanced electrolyser technology;
- Global Gas Logistic Solutions – lightweight efficient fuel containers;
- Ricardo – low carbon propulsion hybrids and storage.
The competitions announced at the conference will have several winners, as the intention is to make funding available to various projects that meet the competitions’ requirements.
The £1 million RSSB competition is for feasibility studies and demonstrator projects. These projects must address one of three key challenges:
- High speed train power – carbon efficient traction energy, reduction of auxiliary energy consumption and energy harvesting;
- Freight traction power – carbon efficient traction energy and improving diesel traction to reduce carbon;
- Infrastructure to support operations – energy storage and distribution including studies on scaling up current technologies and cross modal integration.
The competition proposals need to be submitted by 9 January 2019. RSSB will announce the winning bids in February and produce an initial report on the findings of each successful project in March 2020.
RSSB is also co-funding a scheme for rail carbonisation and energy efficiency initiatives organised by Innovate UK’s Knowledge Transfer Partnership (KTP). KTPs match companies with an academic associate that has the required research expertise and facilities.
For the targeted rail decarbonisation KTPs, there are three funding rounds which close on 12 December 2018, 6 February and 20 March 2019.
Although the Innovate UK KTP call follows the same three challenges as the RSSB collaborative R&D competition, its scope also includes additional areas such as non-high-speed trains and more efficient electric trains, both of which are specifically excluded from the RSSB competition.
Finally, the conference heard how Innovate UK was running a “First of a Kind – round 2” competition on behalf of the Department for Transport. Entitled “Demonstrating tomorrow’s stations and a greener railway”, for which a total of £3.5 million is available, the closing date for this was 28 November. This competition will provide successful entrants with funding to deploy a well-developed technology in a rail environment.
The missing solution
It was good to see the many decarbonisation initiatives presented at this conference. Some of these are already delivering significant carbon savings, whilst others will be powering trains in a year or so. Of these, the Class 165 hybrid being produced by Angel Trains is a welcome development, as it shows the rail industry is starting to follow the automotive sector’s lead in hybrid technology.
RSSB’s competitions will no doubt accelerate such developments and it will be interesting to hear of the winners’ proposals early next year.
Because these competitions form part of the industry’s response to the government’s call for an end to diesel-only trains from 2040, they are bound by government requirements. Reports indicate that the government does not wish the industry’s response to include further electrification, despite this being the only alternative to diesel for high-power traction requirements.
Initiatives for more efficient electric traction are also excluded from the RSSB competition. This seems odd as the electric trains that comprise 72 percent of the UK passenger fleet offer significant potential for carbon savings. At the conference, it was explained that electrification was covered by Network Rail and Railway Industry Association initiatives. As an example, Network Rail’s Wendi Wheeler advised that the company is to specify the requirement to minimise CO2 in is contracts for electricity supply.
The exclusion of electrification from these competitions reflects the UK Government’s view which seems to be that electrification is just too expensive and the solution is better trains without appreciating the space constraints that limit the power of self-powered trains.
Furthermore, as Graeme Clark of Siemens Mobility pointed out, international rolling stock companies must invest in the future of UK rail despite frequently changing requirements with no stable, long term view of rail electrification. Indeed, the boom and bust nature of UK electrification is one reason why it has proved so expensive.
The UK government is right to require the rail industry to accelerate its rail decarbonisation initiatives. In this respect, the competitions launched at the RSSB’s decarbonisation conference have a valuable part to play. Yet the government also needs to understand just how its policy decisions affect the industry’s ability to decarbonise.
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