Reducing energy consumption and emissions from freight transport plays an important role in climate change mitigation. However, there remains a need for enhanced policy making and research to explore decarbonization of freight transport. This research establishes a freight transport model to simulate transport demand, energy consumption and emissions, and applies the model to Ireland with scenarios running out to 2050. This model provides advanced technological details in freight transport modelling, responses of transport demand to economic changes, and behavioural responses in the representation of competition between transport technologies. The results show a strong growth of land freight transport demand in Ireland resulting from economic growth (GDP) despite increasing carbon taxes. The new EU CO2 emission performance standards on light and heavy-duty vehicles have the potential to effectively slow down the growth of energy consumption from 2015 to 2050 but possible technical barriers need to be evaluated to ensure full compliance. In the short term, carbon taxation (or higher fuel prices) may have a greater impact but the effect of emission performance standards will be realised in the longer term as the vehicle stock is replaced with new technology vehicles. Notably, adoption of biofuel and alternative freight vehicles are expected to bring additional reductions in future energy consumption and emissions. For a low carbon future for freight transport, integrated efforts are needed to develop a comprehensive policy agenda (technology specific standards and pricing mechanisms) and promote low or zero emission vehicles technologies, especially for heavy goods vehicles. •Curtailing emissions from freight transport plays a crucial role in climate change mitigation.•Our model incorporates detailed freight transport profiles and behavioural parameters.•Carbon tax results in modest reductions in freight energy consumption and CO2 emissions.•CO2 emission performance standard is potentially effective, but with uncertainties.•Freight demand shift between travel options is less elastic to price signals than passenger demand.