In their evidence to the HS2 Select Committee on Monday, HS2AA argue for a reduction in the top speed of the trains. As well as pointing out that in other countries, high speed railways run at a maximum of 300kph, they give a number of other reasons why a slower speed is better for the environment and communities, as well as for actually operating the railway.
The 360kph speed of HS2 is an issue we have raised many times: designing a railway for such a high speed is the cause of many of the environmental problems from HS2, and it also adds about 10% to the cost of building the railway.
HS2AA point out that reducing the speed will reduce operating costs meaning lower ticket prices and a lower top speed would reduces the technical risks which the project has struggled with since the outset.
It takes 12 minutes to accelerate to 360kph but 7 minutes to accelerate to 300kph. At 360kph, the braking distance is over 3km longer at 10,600m. The energy required is significantly greater.
What’s more government ministers, from McLoughlin downwards have said that the speed of HS2 is less important than the capacity: but capacity of HS2 would be greater if the speed was lower.
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