Project Specific FAQs

For safety and maintenance reasons, no new trees would be planted close to Overhead electricity lines. A landscape and visual assessment will be undertaken as part of the design and Environmental Impact Assessment (EIA) process. Where the assessments determine that visual screening is required, this will be provided within Iarnród Éireann’s lands or lands to be acquired by Iarnród Éireann as part of the Railway Order process.

There is a premium for battery electric carriages over electric carriages, in terms of capital cost and maintenance costs. Therefore, above a certain frequency of service, it is more economical to provide Over Head Electrification as a power source and utilise electric carriages.  
In addition, charging requirements for battery electric carriages can become an issue at end stations when the frequency of service is high.

Iarnród Éireann, supported by the National Transport Authority (NTA), have provision to commission up to 750 electric/battery electric powered vehicles over a 10-year timescale. This order represents the purchase of the largest and most sustainable public transport fleet in Irish history.
 

The batteries will have a minimum life as traction batteries of 9 years on the units. At that point they will still retain a very large capacity and it is most likely that they will be repurposed for a static energy storage system. There is also the option that the batteries can continue to be used as a traction battery beyond 9 years on shorter services requiring BEMU operation.

Battery Electric Multiple Units (BEMUs) are almost identical to the traditional electric DART trains we are familiar with; however, they contain a large battery pack to provide traction power where no overhead line exists.

Both the BEMUs and the EMUs have the same visual appearance, interior layout and performance characteristics, with the only significant difference being that the BEMU will have a traction battery system that allows for operation away from the overhead line system using energy stored in the traction battery system. Battery charging will take place at fixed fast charging stations located at terminus locations and by recovering braking energy.