Smart overhead line switching nominated for ProRail environmental prize.

Energy losses in overhead lines could be cut by 20 to 40%.

December 11, 2008 - KEMA and the German company Elbas have been nominated for the prize offered by ProRail for ideas for a CO2-neutral rail system. By smarter overhead line switching, ProRail can cut annual CO2 emissions by 4 to 7 kilotons. Jury chairperson Jeltje van Nieuwenhoven announced the nominations at a festive gathering in Utrecht on December 9.  

ProRail is working with the business community to find practical and smart ways of realizing a CO2-neutral rail system. Under the slogan ‘From Utrecht to The Hague, calling at Kyoto', the rail network operator has offered a prize to the winner of a three-round competition. The first round, in which businesses were invited to submit ground-breaking innovative ideas, was concluded on December 9, with the selection of three ‘contestants’ who will get the opportunity to develop their ideas into fully fledged plans over the months ahead. In March 2009, one of the three plans will be chosen for realization.  

KEMA has won one of the three nominations with a smart switching concept. Roughly 10 per cent of the electricity transmitted from the public grid to the trains running on ProRail’s tracks is lost. Of the 148 GWh that goes astray, 20 per cent (30 GWh) is lost from overhead lines. That is as much as the combined electricity consumption of every railway station in the country.

ProRail could cut this energy loss by 6 to 12 GWh by fitting smart switches in the overhead lines. The idea behind the smart-switching overhead line is that on twin-track sections of the network, the electrical resistance of the overhead line can be halved by parallel switching. Parallel switching is realized by installing between one and three coupling circuit-breakers in the overhead line’s supply. The 6 to 12 gigawatts saved is sufficient to light every station in the Netherlands for between one and two years. The capital outlay will therefore be recovered in five to ten years.  

In its report, the jury described the idea as ‘attractive, simple and innovative – an eye-catching proposal’. Although the jury queried what it saw as very optimistic figures, it said that the idea was ‘certainly worth developing further and considering seriously’.