From energy management to power management
Power grids are becoming more intelligent to keep energy consumption within a given band thus avoiding cost-intensive load peaks. The 50Hz energy market operates and optimises in 15-minute intervals, which is considered a lengthy period compared to the dynamics found in railway electricity grids. In the Swiss Federal Railway (SBB) power network, the highest peaks typically have a duration of less than one minute, but can be as high as 70MW. For Global Railway Review, SBB colleagues Raimund Feldmann and Andreas Fuchs showcase SBB’s first steps toward a railway smart grid by implementing ‘peak-shaving’. This is when a high performance IT system identifies peak loads, selects appropriate thermic energy consumers, and switches them off for just a short period of time. The authors also explore future potential steps, which may combine load balancing approaches with real-time information from SBB’s Rail Control System (RCS).
WITH 103 trains a day per main track, SBB operates the busiest conventional railway network in the world. Maximising inter-dependent aspects, such as utilisation of the track and electrical grid-capacity along with simultaneous energy efficiency, is a significant issue.
In railway companies, energy is a directly visible entity because it yields operational costs. Energy management is therefore a widely discussed topic. Adaptive train control – or ADL – links dispatching from the train operation centres with operations in the cab and SBB use the technology to minimise conflicts and boost the precision of rail services. An additional benefit is that ADL and EcoDrive save energy: In 2016, 50GWh were saved during a total of 467,000 train control operations, which constitutes a 19 per cent energy savings increase compared to 2015.