Project Specific FAQs

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.

It is currently proposed to use the battery electric trains on the northern line between Drogheda and Dublin City Centre. They will allow us to make full use of existing infrastructure and provide the necessary capacity and frequency uplift on this line while electrification is being progressed. 
 

The electric DART trains will be interoperable across all lines where an overhead electrified line exists. This will be from the City Centre to Maynooth, M3 Parkway, Hazelhatch/Celbridge, and Greystones. 
The first order of electric DART trains will be used to provide additional capacity on the existing DART network at peak times.  
The second order will operate to Maynooth through the DART+ West Project following commissioning of the required infrastructure upgrades.
Subsequent orders will operate via DART+ South West to Hazelhatch/Celbridge as well as be used to increase capacity across the overall network.