About High Speed Rail
Should Ministers decide to proceed with a high speed line, HS2 would be a high capacity railway, designed to standard European high speed specifications, and make use of technology successfully developed in countries like France and Germany. The specifications for high speed rail systems are different to those of conventional UK rail. In order to ensure that new systems built in Europe were compatible with each other and use common standards, the European Union set out guidance and specifications that all countries must adhere to when building new rail lines.
The following sections summarise some of the key statistics and characteristics of high speed rail, setting them alongside other comparable modes of transport. Facts are taken from EU Council Directive 2008/57/EC (the Interoperability Directive).
Access a full copy of the EU Interoperability Directive
The table below shows how top vehicle speeds have increased since 1985. Experts forecast that by 2020 the technology will exist to create a passenger train that can travel up to 400kph.
While 400kph passenger trains do not currently exist, HS2 is designing a track that will be capable of carrying trains up to this speed in the future. It is highly unlikely that a high speed train would be required to exceed this speed in the UK, even if the technology existed. This is mainly due to the fact that the overall time saved at speeds beyond 400kph would be so small that it would not justify the additional energy used and environmental impacts of going faster.
Year 1985 1995 2009 2020
Speed (kph) 270 300 350 400
In order to run at very high speeds, HSR trains need to be far more powerful than conventional trains. They can accelerate at a much quicker pace reaching 100kph in less than 500m or 300kph from a standing start in just over 7km. They are also capable of climbing steeper gradients, which allows them to ‘hug’ the landscape - avoiding the need for so many viaducts and high embankments and minimising noise and environmental impacts.
However, in order to maintain their top speeds, the lines that they travel on must be built with the fewest possible curves – and where curves are unavoidable, they must use larger turning circles to change direction. As you would expect, braking distances must also be longer to allow the trains to slow down safely.
Table 2 shows how high speed rail specifications compare with those of conventional rail travelling at a top speed of 200kph.
Classic HS Rail
Top speed (kph) 200 400
Installed power (MW) 4 20
Maximum gradient incline (%) 1 3
Minimum radius of curvature (m) 1800 7200
Average braking distance (m) 2000 *5500
*Based upon an estimated speed of 350kph on a level gradient.
The train design and the stations serving them must also have different characteristics. Standard high speed trains are built so that two can be joined together for busier services. When combined, they are as long as Eurostar trains (400m) so require very different sized stations.
High Speed trains have higher seating capacities than other modes of transport so stations must be able to cope with large volumes of people arriving at the same time. High Speed stations are more comparable to airport terminals than conventional train stations.
For example, when using approximately ten platforms, it will be possible to run up to 18 trains per hour from one station on a single two-way high speed line. If you consider the capacities mentioned earlier, this translates into nearly 20,000 passengers per hour.
HS Rail Classic Coach Aeroplane
Capacity (seats) 1100 500 50 150
Vehicle length (m) 400 245 - -
Platform height (mm) 760 915 - -