London: the subway mimics roller coasters to save energy

Did you know that simply elevating metro stations can reduce the energy consumption of the trains while increasing their average speed?

British designer Jonathan Hey shares this insight in his latest drawing for his Sketchplanation project (a contraction of “sketch” and “explanation”)… For over 10 years, the stations on London’s Victoria line, the busiest line in the metropolitan network, have been elevated relative to the rest of the line. They are built atop artificial humps.

The incline helps slow down the train when it arrives at the station. This likely also has the side effect of reducing the dispersion of particles caused by braking, which pollutes the surrounding air.

Most importantly, the slope contributes to accelerating the 200-ton train when it restarts, reducing its energy consumption by 5%. Furthermore, the train reaches its cruising speed more quickly, which increases its average speed by 9%.

These are the conclusions of a study titled “Sustainable Energy – Without the Hot Air,” published in 2008 by the late David J. C. MacKay, physicist at the University of Cambridge and scientific advisor to the Ministry of Energy and Climate Change.

This metro simply converts gravity into energy. It applies the basic principle of roller coasters, which harness gravitational potential energy to move naturally. It now seems obvious, but it took some thinking!