TRACTION DECARBONISATION NETWORK STRATEGY
INTERIM PROGRAMME BUSINESS CASE
INTERIM PROGRAMME BUSINESS CASE | Executive Summary| 02 |
change is a real and growing threat. Every year, across the planet,
weather records are broken, and we see more frequent extreme weather,
from flooding to drought. It is
becoming increasingly urgent for countries and businesses across the world, to protect the planet for future generations.
June 2019 the UK Government set out a legislative target to achieve
‘net zero’ greenhouse gas emissions by 2050. For rail specifically the
Department for Transport (DfT) asked
the rail industry to explore
whether it would be possible to remove all diesel-only trains from the
network by 2040 in England and Wales. The Scottish Government also set a
decarbonise domestic passenger rail services by 2035.
railway plays a vital role in supporting the economy and connecting
communities across Britain. It is already the most environmentally
friendly mode of public transport,
contributing less than one per
cent of UK annual greenhouse gas emissions. Rail has the potential to
move large volumes of people and goods reliably with zero carbon
current technology. We have a huge opportunity to
play an important part in a green economic recovery following the
Coronavirus pandemic and tackling climate change.
energy accounts for the vast majority of rail’s carbon emissions. As our
power supply comes from nuclear energy, it is logical that we
immediately focus on reducing diesel
train usage on our network with the ultimate goal of removing them entirely.
the last year Network Rail has worked collaboratively with the rail
industry to establish how we can best work together to achieve this. The
result of this work is the Traction
Strategy (TDNS) and I am delighted that we are now able to set out the
different ways how we could minimise direct carbon emissions from
This strategy sets out why decarbonising rail traction is
so important and considers the three main ways of doing it - overhead
electrification, battery and hydrogen fuel cells. It then
every section of unelectrified line in the country to see where each
solution can be most effectively used. While more work is still needed,
in particular the development of
regional delivery plans, this
strategy will support and inform policy and funding decisions on what
needs to be achieved and when.
Carrying out this work in a way that
is efficient and represents best possible value for money is essential.
This strategy shows that the best way of doing this includes a
and efficient programme of electrification which
will last for at least thirty years, alongside the introduction of new
technology. If we can do this, I am confident that rail will play a
role in helping build Britain back better and achieve the Government’s commitment to achieve net zero by 2050.
Managing director System Operator
INTERIM PROGRAMME BUSINESS CASE | Executive Summary| 03 |
carbon emissions in rail is critical. It brings benefits directly to
the rail industry and, by decarbonising transport overall, important
benefits across the transport sector and wider economy.
These benefits can be organised into six key themes:
Freight End User
Climate Change is a global
Paris Agreement has set
ambitious targets for global
average temperature rise.
Rail is already a green mode
Potential to reduce overall
emissions from transport by
encouraging more people to
choose rail over other forms
Reliability and resilience
need to be improved.
Capacity shortfall in some
areas of the network.
Rail requires significant
investment for ongoing
Cost efficiency is critical.
Introduction of ULEZ and
CAZ around the UK.
Strong focus on air quality
from local, regional and
UK Net-Zero Target.
Getting to Net Zero requires
Net Zero GHG by 2050 for
UK as a whole.
Other national and regional
targets and aspirations for
NR science-based target of
27.5% reduction fortraction
Modal shift from road and
air to rail.
Even better if rail itself is
required to increase
Improving resilience to allow
passengers and freight to
rely on rail.
Achieving cost efficiency
provides sustainable pricing
for passengers, customers
Provide a longer-term
solution to air quality issues.
Support decision making
from rail industry Air Quality
for short-term solutions
programme will require
skilled workers around the
UK to deliver infrastructure
and rolling stock.
Ending rail’s contribution
to emissions by removing
Further minimizing carbon
emissions through optimised
cascade of the cleanest
compliant diesel trains.
Safety improvements for
users compared with roads.
Congestion reduction on
Road maintenance cost
Cross-modal cost saving
with combined refuelling/
Greater tonnes hauled in
same train paths.
Improved resilience through
Reduced rolling stock
Reduced track access
Reduced fuel costs.
Longer-term air quality
solution for stations, depots
Supporting rail industry Air
Quality Strategic Framework.
Increase jobs in design,
“Level Up” economy through
job creation away from
London and South East.
The case for change
THE DECARBONISATION CHALLENGE
INTERIM PROGRAMME BUSINESS CASE | Executive Summary| 04 |
Rail Industry Decarbonisation Taskforce has identified three possible
traction technologies which are sufficiently mature to replace diesel –
battery, electric and hydrogen. Each of
these technologies has different technical capabilities which mean that not all are suitable for all types of rail services.
Battery and hydrogen technologies are
unsuitable for long-distance high-speed
and freight services as these services
have higher energy needs than battery
and hydrogen can provide.
Electric traction is incredibly versatile in
that it can successfully provide energy
for all types of journeys. But it relies on
fixed infrastructure to transmit electricity
and this infrastructure has a relatively
high capital cost compared with battery
and hydrogen technology.
These technical and cost implications
have been used to develop a ‘decision
tree’ to identify areas of the rail network
where one technology is most suitable.
For example, only electrification is
suitable for areas where trains travel
at more than 100mph or where there
are lots of freight services. Equally
the capital costs required to deliver
electrification mean that battery and
hydrogen may offer a better value for
money way of achieving a zero-carbon
railway in areas of the network where
fewer trains run.
INTERIM PROGRAMME BUSINESS CASE | Executive Summary| 05 |
By applying this approach to the 15,400 single track kilometres (STK) of unelectrified rail network in Great
Britain, we have calculated a need to provide:
Of the 2,300 STKs where “multiple options” could be delivered, operational and economic analysis has
identified a further 1,340 STKs of electrification, battery operation over an additional 400 STKs and
hydrogen operation over an additional 400 STKs.
That leaves us with 260 STKs of infrastructure where no clear decision has yet been made but a likely
technology is identified within the TDNS National Recommendations document. Further work at a local
level will be needed to confirm this.
In some areas of the network which are particularly busy electrification may also represent the most
sensible option, even though it would be technically possible to use battery and hydrogen. These areas of
the network are identified as ‘multiple options’ where further economic and operational analysis is needed
before the best choice of technology can be decided.
Up to 100km
Reduced usage Reduced usage
operate on the
11,700 STKs of
Battery operation over
400 STKs of infrastructure.
Hydrogen operation over
900 STKs of infrastructure.
2,300 STKs where there is
no clear technical choice.
Baseline ElectrificationThird Rail
(Future strategic work)
INTERIM PROGRAMME BUSINESS CASE | Executive Summary| 06 |
Projects and programmes which increase
capacity for passengers and/or freight
should continue in order to support
a modal shift to rail. These projects
and programmes could draw on the
strategic and economic benefits of
decarbonisation and modal shift in their
business case. This is especially true for
freight projects because of the significant
modal shift they deliver.
A stable and efficient programme of
traction decarbonisation is the most
efficient way for us to deliver this work and
will enable us to incorporate all the lessons
learned from previous electrification. This
programme is also likely to include interim
solutions to make the most effective
use of resources and keep disruption to
passengers and freight to a minimum,
while meeting emissions reduction targets.
This programme will be considered as part
of the TDNS programme business case.
Any proposed new railway should consider the need
to operate using zero carbon rolling stock (i.e. battery,
electric or hydrogen), in conjunction with the wider
network to which it is linked.
Battery and hydrogen train operations should now
start wherever this is possible to ensure standards
are developed, whole-system operational experience
is gained, and lessons are learned. That way, best
practice can be learned and embedded in good time.
From now on, diesel-only trains should
only be bought where there are clear
strategic and economic reasons for doing
so. Where this is necessary, only trains
where the possibility exists in future to
replace the diesel engines with a zero-
carbon alternative should be chosen.
Hybridisation and the use of multi-mode
trains offer an excellent opportunity
to progressively reduce emissions and
realise the benefits of electrification.
INTERIM PROGRAMME BUSINESS CASE | Executive Summary| 07 |
economic case considers the economic impact of minimising traction
emissions and provides an indicative assessment of the net economic
value from the different ways of doing
this. The results establish
an initial, nationwide view of the potential costs and benefits from the
recommendations. It should be stressed that this analysis provides an
view of benefits and costs and has been based on a number of assumptions.
from the significant environmental benefits of reducing rail-related
carbon emissions, there are also a number of economic benefits that
could be realised:
The economic analysis undertaken relates
specifically to the costs and benefits we would expect to see from
traction decarbonisation. It is likely, however, that as traction
projects or programmes are brought forward, they will have their scope
enlarged to include other railway work that is needed. Working in this
way helps to minimise
disruption to passengers and maximise overall
efficiency. In those cases, we would expect both costs and benefits to
be higher because more work is being carried out.
AND RENEWAL COSTS
TRAIN FUEL COSTS TRAIN LEASE COSTS
The value of journey time
savings from improvements
in the acceleration and
deceleration of trains.
The value of more reliable
passenger journeys due to
improved reliability of trains.
The value of reduced CO2
emissions emitted into the
The value of reduced congestion
on the road network as more
people and organisations choose
rail over road.
A range of capital and renewals
costs over time, reflecting the
cost of overhead electrification,
hydrogen refuelling points, and
battery charging points.
maintenance cost of
The cost of increased
times from reduced
rail services during the
construction period for
new or upgraded rail
Changes in maintenance
costs according to the
mileage covered by
each different type
of passenger train in
Changes in fuel costs
according to mileage and
consumption rate covered
by each type of passenger
train in operation.
Changes in lease costs
due to the different types
of passenger trains in
Changes in track
maintenance costs due
to the mileage covered
by each different type
of passenger train in
INTERIM PROGRAMME BUSINESS CASE | Executive Summary| 08 |
AVERAGE ANNUAL STKs
MAXIMUM STKs IN
ANY ONE YEAR
Pathway 1 (-80%) 259 377
Pathway 2 (-95%) 303 447
Pathway 3 (Net-Zero by 2050) 355 691
Pathway 4 (Net-Zero by 2040) 658 922
Pathway 5 (Net-Zero by 2061) 303 447
Most of the railway in London and South East is already
electrified which means that most of this programme will
be delivered in other parts of the country, drawing on skills
and resources in those regions. The Eastern region has the
largest volume of electrification required, but there are
significant volumes in all regions outside the South.
With a total length of over 13,000 STKs in need of
electrification and recent supply chain activity average of
450 STKs per year having fallen to much lower levels, there
is a clear challenge to re-build our capability to efficiently
Analysis undertaken by RIA, shows that delivering 450
STK of electrification per year is within the capability of
the supply chain, assuming that activity is gradually built
up over several years and a commitment is made to a
stable and efficient programme of work. This stability is
critical to ensuring that jobs are retained, the need for
additional training is reduced and the programme is a
A highly skilled and specialised workforce is also needed
to deliver this work, and this could be efficiently achieved
by employing specialist delivery teams that consistently
move from project to project, each delivering 75 to 100
Five different pathways for delivering decarbonisation have been developed. These help funders consider
the trade-offs which need to be made around the degree of decarbonisation achieved, the pace of delivery
For all five pathways costs and benefits are broadly balanced over a ninety-year appraisal period and those
pathways which provide higher emissions reductions offer the best value for money when delivered over
a longer period.
All except pathway 4 are feasible based on the industry’s assessment of delivery capability. Further work is
being undertaken with RIA and the supply chain to validate this.
DELIVERY OPTIONS FOR CONSIDERATION
INTERIM PROGRAMME BUSINESS CASE | Executive Summary| 09 |
capital expenditure arises from the cost of overhead electrification
and to identify these costs we have assessed the complexity of the work
to be undertaken on each part of the
network that needs to be
electrified. This considers the length of the section, the engineering
complexity (for example, tunnels and bridges), the economic cost of
disruption while the work is
carried out and the likely duration of
the project. Capital costs at this stage have been estimated using a
wide total cost bracket spanning from £1m/STK to £2.5m/STK (2020
Capital cost of battery charging points and hydrogen
refuelling locations were determined using preliminary estimates from
RSSB’s T1199 project. These costs were then scaled
according to the number of battery and hydrogen trains required in the recommended areas.
of the recommendations suggests that between 3,600 and 3,800 electric
and 150 and 200 battery and hydrogen trains will be required for the
recommendations but the need for interim
solutions will likely increase the number of battery and hydrogen trains
needed in the short-term. Around 650-700 freight trains will also be
required and are likely to be delivered as a mixture of electric and multi-mode vehicles.
The delivery of this strategy is subject to funding from HM Government, the Scottish Government, and the Welsh Government.
decarbonisation projects and programmes will be decided by working with
industry stakeholders and will be presented in the TDNS programme
business case in October 2020.
The delivery of decarbonisation
projects and programmes is devolved to Network Rail regions who are now
working with Network Rail System Operator to begin to develop regional
traction decarbonisation strategies and identify early schemes to take forward.
Once decisions have been made to develop or deliver schemes, those projects will be governed by the RNEP and GRIP processes.
further important consideration is that this decarbonisation programme
will need careful integration with other major national programmes such
as the Long-Term Deployment Plan
(Digital Railway), Northern
Powerhouse Rail, High Speed Two and projects arising from the rail
industry Air Quality Strategic Framework. The programme will be able to
highlight areas of
potential conflict but further work will be
required beyond October 2020 to resolve these issues and ensure all work
is smoothly integrated and delivered as efficiently as possible.
DELIVERING TRACTION DECARBONISATION