Public Transport, including rail, will, have to play a significant role in the national mitigation effort and investments being made in public transport and sustainable transport measures in order to promote modal shift will be critical in this regard. As part of Ireland's effort to contain emissions and mitigate climate change, I am dedicated both to increasing the capacity of our public transport system and to facilitating the uptake of low-emission vehicles and technologies within the public transport sector.
The Government is committed to furthering the progressive development of electric fuelled public transport, particularly along high demand routes in the GDA where capacity requirements make such investment cost-effective. Rail already plays an important role in meeting increased passenger demand while also providing an energy-efficient mode of transport. The rail sector accounts for only 1.1% of transport emissions. Electrified rail use, in particular, is capable of achieving low emissions through utilising renewable sources of energy. Rail operators are also already playing an active role in emission reductions on existing services, introducing a range of technical measures including automatic engine shutdown, configuring train length to match passenger demand and installing traction control software.
Considerable progress has already been made on increasing capacity on the electrified light and heavy rail networks through the Luas and DART networks. In terms of future investment plans, the Metro system is due to commence construction in 2021 with passenger services starting in 2027 while funding of the DART Expansion Programme will allow substantial progress on electrification of the Northern rail line as far as Balbriggan - now expected to be delivered in 2022 - and commencing work on the Maynooth line. The DART Expansion Programme also has a key role to play in delivering an efficient transport system that will deliver a very substantial increase in peak-hour capacity on all lines from Drogheda, Maynooth, Greystones and Hazelhatch on the Kildare line while also contributing to the overall aim of combating climate change.