Electric railway traction systems and techniques for energy saving

Energy saving in the railway sector is a major consideration for current operators. This is driven by the continuing focus of environmental concerns, together with an increasing uncertainty about the availability and cost of liquid fuels. The extended cycle life of railway equipment means that decisions influencing traction systems can have lasting consequences of up to 50 years. This article describes the fundamentals of railway vehicle kinematics and then analyses a number of notable recently implemented energy saving strategies. These include regeneration, use of energy storage, train control and optimisation, and operational effects.