December 2022

Vectos’ Carbon Reduction Strategy Support Tool available

Vectos (part of SLR) has co-authored the new SUMP Topic Guide on Decarbonisation of Urban Mobility, alongside EIB/JASPERS, Rupprecht Consult and University College London. The guide is now available and provides hands-on advice to practitioners on mainstreaming climate change mitigation in SUMPs. Recommended in the guidance is use of the Carbon Reduction Strategy Support Tool. Developed by Vectos (part of SLR) on the SUMP-PLUS project, this tool helps cities understand the mix, scale of ambition and timings of “Avoid, Shift and Improve” policy strategies needed to meet net-zero carbon targets.

The new SUMP Topic Guide on Decarbonisation of Urban Mobility recommends Vectos’ (part of SLR) Carbon Reduction Strategy Support Tool for cities when planning pathways to net-zero carbon.

The Carbon Reduction Strategy support tool, developed by Vectos (part of SLR) working on the SUMP-PLUS project, is an open-source tool available for all municipalities to use to better understand the mobility policies required to reach carbon-zero.

The net-zero challenge

The transition to achieve net-zero carbon targets by 2050, or even sooner, requires radical and urgent change to existing policies. However, cities often lack the knowledge and expertise to understand how different scales and timings of policy strategies impact on carbon emissions, especially when dealing with such long timescales as up to 2050. To address this knowledge gap Vectos (part of SLR) has developed the Carbon Reduction Strategy Support Tool, to assist cities in identifying a suitable mix of high-level policy strategies, and their timings, that will achieve carbon targets while also respecting and supporting the other objectives that cities are looking to deliver.

What does the tool look like and what can it do?

The tool is in the form of an Excel spreadsheet, dealing only with personal travel, not freight; it calculates the expected impacts, over time, of introducing different carbon reduction strategy mixes, and can be used iteratively with groups of stakeholders, trying out different combinations to find the most effective and acceptable mix of strategies. It provides an aid to ‘backcasting’ – working backwards from an agreed output to identify what needs to be done, between now and then. Instructions are provided within the tool, and additionally, a user guide is available with a more detailed description, examples of how to use the tool and explanations of the outputs.

City users specify some basic information on base year information in their city (e.g., modal shares and trip distances by purpose), and expected population growth, to 2030 and to 2050.

They then can experiment with different scale of ambition and timings for a set of , the tool presenting the quantified carbon reduction implications of the input selections in the form of:

  1. A ‘waterfall’ diagram, showing the contribution of each strategy to the overall carbon reduction, at a given target date.
  2. A ‘fan’ diagram, showing the contributions to carbon reduction, year by year.
  3. A cumulative distribution diagram, showing cumulative carbon emissions, over time.

If the required targets are not achieved, the user can review the situation and adjust the strategy mix; this might involve increasing the scale of ambition for a particular strategy or delivering a strategy at a faster rate.

Multiple different mixes of policy strategies can be adopted to achieve the common end goal – according to local conditions and capabilities. Therefore, the process of establishing the most suitable policy strategies for long-term net-zero carbon planning requires extensive stakeholder engagement among many sectors. This tool is useful for cities as an aid in stakeholder and political engagement activities to help inform workshop discussions and decision making when developing long-term policy strategies and defining transition pathways to net-zero carbon.