WP3: Rail Passenger Transport - TOSCA Project

At a later stage (say by 2025 and beyond) this technology may be co-ordinated with rail traffic
control, i.e. traffic flow management, which would lead to further improvement. Such measures
would also enhance railway’s transport capacity to some extent. In the long term (2050) ecodriving
is estimated to save a further 5–10 % compared over the first generation, used as a
single technology. However, there are interactions with other technologies; see further
combination scenarios in Section 3.5.
PG. Dual mode and hybrid trains
In a dual mode train electricity is used on electrified sections while diesel or bio fuels are used
on non-electrified parts of the operation. Today most trains running on both electrified and
non-electrified sections use diesel power only. Depending on the share of electrified sections in
the actual operation, and carbon content of electricity, energy savings and emission reductions
can be in the order of 20–50 % and sometimes more, compared with pure diesel operation.
Another possibility is hybrid diesel-electric propulsion with on-board energy storage. These
technologies are available today, but are sparsely used. It is expected to be further matured and
accepted during the next 10 years. Maximum market penetration is limited to diesel-hauled rail
services, i.e. around 10–12 %. Further incentives are likely necessary for a wider introduction.
PH. Bio fuels in diesel engines
As an alternative to diesel fuel, diesel engines can be powered with liquid or gaseous bio fuels,
which can reduce life-cycle GHG emissions. WP4 of TOSCA (Perimenis et al, 2010), suggests
Hydrogenated Vegetable Oil (HVO) as the most promising alternative available today. The net
life-cycle content of CO2-eq is about 45 % lower than for ordinary diesel fuel, while
production cost for HVO is about 50 % higher. In the longer term a new generation of bio
fuels, produced from wood, is anticipated to be available.
Most important, the future availability of biomass for energy purposes depends on the amount
of land that is not needed for food production (non-food areas) and other purposes. This is a
very uncertain issue. Therefore, the biomass potential is also highly uncertain and requires
much further analysis. This is out of scope in this study on rail passenger transport.
Due to the limited market penetration in rail operations (an absolute maximum of 12 %, i.e. the
share of diesel operations) and, in particular, the high uncertainties in future large-scale
availability, this option will not be further analysed in this report. The bio fuel option will be
further evaluated by WP6 in Stage 2 of TOSCA, as a scenario variable.
PI. Electrification of non-electrified lines
Electric rail operations are usually more energy efficient than less GHG-intensive than diesel
operations, in particular if electricity is partly generated by other means than fossil fuels. This
is shown in Table 2-1, where the electric ‘Intercity or regional’ train has lower GHG emissions
per passenger-km than the diesel train, despite higher speed and higher train mass per seat.
Today, several European countries have very limited part of their rail networks electrified.
Plans for improvements have been presented, for example in the UK. In these countries
substantial reductions of GHG emissions from rail operations are expected, in particular if
‘Low-GHG electric power’ is used in the future (see further FJ below). Massive electrification
to cover, say, 95 % of all European rail passenger transport volumes (instead of the present-day
88 %) would reduce GHG emissions by 3–8 % depending on the electricity mix.
The limited general impact – because of the low additional market penetration – and the
associated cost of electrification is a matter of optimization (i.e. what lines should be converted
to electric operation). This is however outside the scope of this study. Therefore no further
analysis of electrification is made here. This does not exclude that certain lines could and
should be electrified after a thorough analysis.
Deliverable D4 – WP3 passenger 10