In Nicola Anderson’s words, the future is: electrifying!

By some estimates, electrified railways in industrialised countries constitute over 30 per cent of the world’s rail infrastructure. The first electric train lines in the UK were built in the latter part of the 19th century. Nowadays, almost 60 per cent of UK rail journeys are by electrified trains and this percentage is likely to increase in years to come.

One of the main reasons for the growing prevalence of electrified trains is their environmental efficiency. As well as being more powerful and cheaper to run, electric trains tend to be lighter with fewer moving parts. Assuming the government’s electrification programme continues, more electric trains will be introduced to the country’s rail network in the coming decade.

The two most commonly used methods of electrification are by overhead lines and conductor rails. Both require uninterrupted connection of the train to the electric grid. If the electrical connection is broken, the train will come to a standstill. This situation could also pose a significant health and safety risk, as direct contact with the conductors can cause serious injury or even death.

To mitigate this risk, an improved rail transportation system has been developed by engineers from French research laboratory, Metrolab – a joint venture between Alstom and RATP. Metrolab’s main objective is to develop technology for the ‘automatic metro of the future’.

The patented technology (3032921) discloses a rail transportation system, which includes a series of energy storage modules, based on supercapacitor cells. The main advantage of these supercapacitor cells is that they can re-charge more quickly and efficiently than lithium-ion cells for example.

Making use of this innovation, railway infrastructure designed by Metrolab is able to re-charge trains quickly at each station along the route. For example, on arrival at a station, the storage modules can be connected to their respective power distributors. Each carriage is equipped with an extendible arm, which connects the supercapacitor module to the grid, allowing charging to commence. The system has a variety of electrical controls, which monitor the charge of each supercapacitor cell, minimising the risk of under or overcharging. To avoid the risk of electrocution, the power distributors can be disconnected from the grid when no train is present in the station. Before departure, the extendible arms are retracted, allowing the train to resume its journey.

When travelling between stations, the train draws power only from its own supercapacitor modules. This effectively removes the need for third rails or overhead cables. The storage capacity of each reservoir is between 10 and 20kWh per carriage, facilitating uninterrupted operation over short distances. In addition to providing traction energy, the supercapacitors provide electricity to auxiliary devices, such as air conditioning and lighting systems. As it approaches the next station, the train is able to harvest kinetic energy generated while braking.

Close review of the prosecution history of this French patent reveals that the granted claims were almost identical to the claims submitted by Metrolab in its original application. In this instance, the claims include, amongst other things, relatively broad terms such as ‘a train’ and ‘a storage device’. French national patents cannot be rejected due to a lack of an inventive step during examination, as they can in most other countries. The result is that patents can currently be more easily granted in France than in other countries. However, Law has just been passed which will introduce the examination of inventive step by the French patent office, bringing the standard of examination of French national patents to a more similar level to that of its major European neighbours such as the UK, Germany and the European patent office.

This means that Metrolab has managed to obtain a granted patent which has a relatively broad scope – an important achievement, given its involvement in a new field of technological innovation. The patent could therefore be used to deter competitors from constructing this type of fast-charging infrastructure without a licensing agreement with the patentee.

From an IP strategy perspective, this patent demonstrates the value of filing a technology in the broadest terms possible to prevent others from eroding their commercial potential.

Nicola Anderson is a patent attorney at European intellectual property firm, Withers & Rogers. She advises innovators in the rail sector about how to protect their inventions