New SLoCaT Report: Transport Sector Shows Substantial Mitigation Potential, but Achieving 2DS by 2030 Remains a Challenge

INDCs show promise for transport but require further ambition to meet targets

The Partnership on Sustainable, Low Carbon Transport (SLoCaT) has launched a new report, “Emission Reduction Potential in the Transport Sector by 2030,” to determine the magnitude of mitigation possible in the transport sector by 2030 through low carbon policies proposed to be implemented in individual countries. This study is the first known attempt to compare different transport related INDC scenarios against the two-degree scenario (2DS) of the International Energy Agency (IEA), which is generally recognized as a reference scenario for low carbon development within the transport sector.

The report assesses a Business-as-Usual (BAU) scenario, as well as two hypothetical variants of a Low Carbon Scenario (LCS) (average and aggressive) based on available mitigation potential studies, and three different variations of INDC transport related targets.

From 1990-2010 the transport sector was the largest energy consuming sector in 40% of countries worldwide, and in most remaining countries, transport was found to be the second largest energy consuming sector. In 2010, the transport emission share of economy-wide emissions in low-, middle-, and high-income countries was 3%, 8% and 22%, respectively. The average emission intensity of transport CO2 emissions relative to GDP decreased 58% between 1990 and 2010.

Key Findings

Transport emissions in 2030 must be below 2010 levels in order to be in line with 2DS scenario. This analysis shows an emission gap in 2030 of about 3.4 Gt (a 42% gap) between BAU and 2DS projections for the 138 countries assessed in this report. Only about 10% of INDCs have proposed a transport sector emission reduction target, and about 9% and 15% of INDCs, respectively, include estimates of country-level BAU projections and transport sector mitigation potential.

The LCS projections developed for this report reveal that by 2030, transport emission intensity relative to GDP could decrease by 59%, compared to the 46% emission intensity decrease in the BAU scenario. With implementation of an LCS, the BAU emission gap of 3.4 billion tons relative to 2DS (a 41% gap) could be reduced to about 1.5 billion tons (a 23% gap). Investigations carried out by various institutions project an economy wide emission gap of 11-16 billion tons of CO2 between 2030 economy wide targets submitted in INDCs and a 2DS.


The analysis concludes that based on current emission trajectories, expected LCS projections and actual transport emission targets, the mitigation ambition in current INDCs will not be sufficient to achieve a 2DS within the transport sector by 2030.

Of the three approaches used in this analysis to compare derived INDC transport targets only one would be close to the 2DS scenario and this is judged to be the least likely of the three approaches.

The outcome of the analysis is cause for concern. If the scenarios described in this document materialize it means that the transport sector would be not well placed to make a long term contribution to the 2DS (i.e. by 2050 or 2100). Investments would have been made up to 2030 that would lock in emission patterns that, at least for the medium term, are not compatible with the 2DS. This will require in the short and medium term much deeper reductions from other sectors which may not be possible or cost effective, thus substantially increasing the difficulty of an economy wide transition to a 2DS pathway.

To address the emission gap, low carbon policies (incorporating ‘Avoid,’ ‘Shift,’ and ‘Improve’ strategies) must be scaled up and accelerated to approach a 2DS within the transport sector A more aggressive implementation of low carbon policies (both in scope and intensity), would position the transport sector better to reach 2DS requirements, if not by 2030 then beyond.

The full version of the report is available here.