Running electric railways directly from sunlight may be a cost-effective way of expanding both photovoltaic energy generation and railway electrification in the UK and around the world, according to a report from Imperial College. Originally triggered by a movement that sprang from an anti-fracking protest, the idea led to a feasibility study and may end up in pilot projects. The report, Riding Sunbeams, proposes installing photovoltaic panels directly alongside railway lines and transmitting the electricity generated directly into the railway system as traction current, without first distributing it to the grid. This would take advantage of a coincidental match between the peak generating time for solar and a peak demand for traction current, but would bypass current problems in many areas of limited grid capacity. “Many railway lines run through areas with great potential for solar power but where existing electricity networks are hard to access,” explains Prof Tim Green, director of the Energy Futures Lab at Imperial College London. It would also potentially free up many sites for photovoltaic development. The Imperial project began when the residents of Balcombe, a village in West Sussex, opposed proposals for test drilling to establish whether the area might be suitable for shale gas fracking. The protest inspired the establishment of a co-operative called Repower Balcombe, which aimed to generate the village’s entire electricity demand via renewables. One stumbling block to this goal was that the local grid did not have the capacity to accept any more solar energy without costly reinforcement. Prof Green, who lives in Balcombe, decided to look into the possibility of using solar power directly on train lines. “Quite quickly you realise that the answer might be more than the solution to one village’s problem and something to unlock untapped solar resource on a much wider scale,” he said in the foreword to the report.
The Engineer 21st Feb 2018 read more »