Electrification costs.
HS2 construction reveals lower electrification costs
most recent tendering process to select contractors for the construction of HS2 includes an installation requirement for 589 single track kilometres (366 miles) of overhead wiring that involves 62 viaducts, 293 bridges and 15 tunnels.
The design for the catenary has already been chosen. It will be built under licence from SNCF Réseau, the infrastructure division of the French national railway, using its V360 OCS design range which is the first system in Europe to be certified for speeds of up to 360kph (225mph). It is a modular product that will allow future HS2 contractors to use a range of suppliers.
The requirement covers Phases 1 and 2a of the route, with Royal Assent for the latter section between Birmingham and Crewe expected later this year. Authority for building Phase 1 has already been given by Parliament.
The estimated value of the contract is notable because at £300 million the cost is a little over £0.5m per single track kilometre (stk), which is a long way below the aspiration of the Railway Industry Association to reduce the cost of installing overhead line catenary on existing routes to £1m per stk.
This follows the disastrous outcome of the Great Western Main Line project, where £3m per stk was spent - with the result that a number of electrification projects in Britain were cancelled because they no longer represented value for money, most notably the Midland Main Line route to Nottingham and Sheffield.
If the suggested cost for HS2 wiring is delivered this will open up new opportunities to justify proposals elsewhere, although as a new build the need to rebuild bridges and other infrastructure to provide necessary clearances will not be a feature of the construction.
This may be less of a constraint in the future when existing infrastructure is electrified as a result of a new technical initiative to prevent flashovers, which in the past has meant that significant clearance must be provided between overhead wiring and structures. The innovation is a new surge arrester that has been approved by Network Rail, and which was used for the first time in December 2019 by Siemens in the Cardiff area, where the proximity of a canal prevented other solutions.
There continues to be an environmental agenda to promote significant network electrification, which will have improved financial justification if installation costs can be reduced. However, there may be other constraints if the scale of work required for HS2 leads to a shortage of contractor expertise and resources.
It will be recalled that one of the reasons identified for the cost escalation of the GWML scheme was that other projects in hand meant that both design skills and installation experience was not available in sufficient quantity. This caused labour costs to rise, although there were significant planning deficiencies as well.
The timing of the future HS2 requirement works well for contractors, as the resources involved in the East Midlands route electrification to Corby will be available for transfer to the project - allowing skills to be retained.
Wider ambitions for the rail industry were outlined in the Government’s Decarbonising Transport report, published in March this year and which identified that minimal use by the freight operators of electric traction was a major contributor to industry CO emissions.
It provided statistics for 2018-19 that showed total rail freight emissions amounted to 476,000 tonnes, 95% of which (454,000 tonnes) emanated from the use of diesel locomotives. Emissions from passenger operations using diesel traction amounted to 55% of the sector total (1,394,000 tonnes), which will decline as current wiring projects are energised and greater use is made of bi-mode trains on a number of routes.
Additional network electrification has had little effect on freight operations, with lengthy transits continuing to be diesel-hauled ‘under the wires’.
In February 2018, Network Rail established a team to develop a Traction Decarbonisation Network Strategy, by analysing all nonelectrified routes in order to determine the long-term approach to reaching zero carbon operations and the use of new technology such as hydrogen and battery power.
Industry suppliers have been making their own assessment of future needs and consider that providing throughout electric haulage of freight intermodal services from the major ports at Felixstowe, Southampton and London Gateway is likely to be a priority.
The previous constraint to electrifying routes that make up the Strategic Freight Network has been access to non-electrified terminals, given that changing traction and traincrew is an uneconomic proposition. A typical example is the new London Gateway port, located on the four-mile Thames Haven branch which joins the network using the electrified Tilbury loop.
The replacement of life-expired BR traction by the privately-owned freight operators was focused on the robust Class 66 design built by General Motors, rather than any new electric types. In any case, there was a surplus of the dual-voltage Class 92 electric locomotive available, as the anticipated level of International transits using the Channel Tunnel did not materialise.
The need for bi-mode operations was not actively considered - although it was not a new proposition, as demonstrated by locomotives built for BR Southern Region operations. The longevity of this Class 73 type, dating from 1961, reflects output of 1,420hp from third rail electric current with a 600hp diesel engine to operate in yards and reach terminals.
The concept was revived in 2015 by Direct Rail Services, with service entry of a modernday Class 88 bi-mode design providing much greater electrical power at 5,360hp when using overhead current collection and a diesel engine offering an output of 940hp - again aimed at connectivity with unelectrified lines and terminals.
A development of the Class 88 type is now available from Stadler which has greater diesel power to enable haulage over longer distances. Designated as Class 93, it has a maximum speed of 110mph and can produce an output of 5,440hp for electric haulage and a much improved 1,800hp when the diesel mode is used. It was reported at the end of 2018 that the Rail Operations Group had placed an order for ten machines, but as yet it has not been confirmed when delivery can be expected.
There remains the concern that as better business cases for electrification are made, the available design and installation capacity may become a delivery constraint.
“If the suggested cost for HS2 wiring is delivered this will open up new opportunities to justify proposals elsewhere.”