Good to know
The train as a power station
Rhaetian Railway trains require energy so that they can go up the steep mountain tracks. The locomotives and trains get this energy from the power grid which they are connected to via overhead lines. But RhB doesn’t just consume electricity and energy during its journeys. It also produces energy. The modern Ge 4/4 III locomotives and the new ALLEGRA railcars are like small power stations. So how does that work exactly?
Practical: Using braking power
The recent generation of RhB locomotives and the ALLEGRA railcars are equipped with so-called regenerative brakes. If the machine brakes, the heat which thus emerges – the kinetic energy – is converted back into electrical energy thanks to these special brakes. This reclaimed energy is fed directly back into the power grid so that it can be used to power other locomotives and trains. In concrete terms this means that four descending trains generate suffi cient energy while braking for one train to go up the mountain. This principle of energy retrieval is known as recuperation, from the Latin „recuperare“, meaning „to reclaim“ or „to recover“.
People and technology
The amount of energy which can be reclaimed depends on various factors. In addition to having new, energy-efficient rolling stock, the position of the locomotive is also a decisive factor for example. The locomotive should be at the rear of the train during a descent in order to reclaim as much energy as possible. There is also a human contribution to be made. The training of engine drivers and other train operation workers will make even greater energy savings possible.
Recuperation is not limited to the railways. It also occurs on buses and trams and in cars. On buses and trams the energy is returned to the power grid via overhead lines as it is for RhB. In electric and hybrid cars with regenerative brakes the emergent energy is transmitted into an energy store in the vehicle and then distributed from there.