3.11. Strategic Goal 3: Promoting the Sustainable Use of Energy in Transport 3.11.1. The main drivers for growth in the Irish transport sector include increasing population and employment, which has led to increased demand for housing, urban sprawl, long-distance commuting, and greater freight transportation. It is recognised that transport plays a pivotal role in supporting economic growth and balanced regional development with the total primary energy requirement (TPER) of the transport sector showing a close positive correlation with GDP. 3.11.2. However, it is imperative that growth in energy consumption in the transport sector is decoupled from economic growth in order for the transport sector to move along a more sustainable trajectory. The objective is to develop a transport system, which will allow for the maintenance of economic competitiveness by removing infrastructural bottlenecks and achieving security of supply through a diverse fuel mix, whilst increasing social cohesion and access for communities in peripheral rural areas and reducing environmental impacts. 3.11.3. This requires the provision of supply-side infrastructure through capital investment along with the implementation of a complementary range of demand side management measures such as fiscal incentives and regulatory instruments in order to encourage a modal shift from private to public transport. 3.11.4. In November 2005, Transport 21 was launched, which is a 34.3 billion capital investment framework for the transport system for 2006 to 2015. Overall 18.5 billion will be invested in the national roads programme, which will upgrade national roads, remove bottlenecks, reduce congestion, improve journey times and, consequently, improve competitiveness. Furthermore, 15.8 billion will be provided for public transport projects, in a significant rebalancing of public expenditure, which will encourage commuters to switch to public transport. 3.11.5. It is expected that this will achieve a fully integrated transport system with 75 million additional passenger trips per annum on DART/suburban rail services, over 80 million additional passenger trips on Luas/Metro services, a 60% increase in bus capacity, an extension of the motorway network to all provincial cities and an upgrading of approximately 850 kilometres of other national roads by 2015. 3.11.6. Modelling of the impacts of Transport 21 in the Greater Dublin Area shows a reduction of almost 20% in fuel consumption