A new report from C40 and McKinsey gives mayors the best guide yet as to priorities to achieve zero carbon cities

By C40 Executive Director, Mark Watts

At the COP23 Climate negotiations in Bonn, C40 and McKinsey, published a new report, ‘Focused Acceleration’, which will enable mayors to assess the ambition of their own climate plans against the modelled analysis produced by McKinsey and Arup. The analysis showed that if resources were concentrated on a small number of key policies and actions across the majority of cities, then C40 members can demonstrate that it is possible to cut emissions in line with the Paris Climate Agreement targets. 

‘Focused Acceleration’ builds on C40 and Arup’s previous analysis, ‘Deadline 2020’, which modelled the pathway for major cities to reduce emissions in line with the Paris Climate Agreement targets. It suggested that most cities need to peak their emissions by 2020 and by 2030 average GHG emissions across all C40 cities need to be 3 tonnes per person per year or less (against the current projections of an average of 9 tonnes per person). C40’s mayoral Steering Committee later voted to make it a condition of membership of C40 that every member city should publish an action plan that is in line with the Deadline 2020 findings.

Like C40’s previous analysis, ‘Focused Acceleration’ finds that it is possible for major cities to decarbonise fast and deeply enough to meet the Paris Agreement goals. But there is now an incredible urgency to get on track.

While cities operate as systems and so any single intervention needs to be considered as part of an holistic strategy, McKinsey’s analysis distilled the 450 possible actions which Deadline 2020 identified down into twelve priority opportunities across four action areas. At the bottom of this page, you'll find three graphics which outline the flavour of the findings (all relate to what needs to be achieved by 2030, unless stated otherwise).

Decarbonising the electricity grid

By 2030 the proportion of electricity that needs to be supplied by zero carbon sources ranges from 70% in middle income mega-cities, to 90% in small high income innovator cities. 

Optimising energy efficiency in buildings

By 2030 the majority of privately owned buildings will need to have been retrofitted to high energy efficiency standards in all categories of cities except the two lowest income groupings (where the primary focus is on new build). In the two highest income categories, 95-100% of privately owned buildings will have been retrofitted.

Enabling next generation mobility

By 2030 over three quarters of trips will be made by walking, cycling, or mass transit in currently middle and low income cities. It is expected that high income cities will lag somewhat behind, because of the existing dominance of private cars. 100% of municipal buses need to be zero carbon across all C40 cities. 

A critical enabler of low carbon mobility is that planning regulations curb suburban sprawl. The model estimates that increases in density ranging from 3% to 10% will need to be achieved by 2030.

Improving waste management

By 2030 at least 20% of waste needs to be diverted from landfill and incineration, even in low income mega-cities, where today a large proportion of waste is not even collected. In high income cities the figure needs to be at least 70%, although many cities already have more ambitious targets.
From analysis to action

The report is entitled ‘Focused Acceleration’ for a reason: by delivering the key targets outlined in the report  cities could achieve 90 to 100 percent of their overall 2030 emissions targets and build the knowledge and foundational capabilities needed to reach net zero carbon by 2050.

At the same time, the incremental investment required to achieve 2030 emissions targets is significant:  roughly $50 to $200 per metric ton of CO2  equivalent.  However,  all opportunities provide a positive return on investment in the mid to long term,  whether through direct cash flow for investors (for example,  in the case of renewables and efficiency improvements) or broader boosts to economic activity in the city (for example,  transit-oriented development).  For many opportunities,  up-front investments are paid back within five to ten years.

At C40 we will now be discussing the analysis with each of our member mayors, along with their senior staff, as we support each city to publish an action plan that is in line with the Deadline 2020 goals. Thanks to generous new funding from the British and Danish governments, we now have a lot more resource with which to do this.

We will also engage with member cities through our seventeen best-practice sharing networks, to identify the groups of cities that might want to take a lead in committing to specific targets, like those suggested by the ‘Focussed Acceleration’ analysis. This could take the form of more initiatives like our Green and Healthy Streets declaration, through which 12 C40 mayors set out concrete plans to stop purchasing any fossil-fuel powered buses by 2025, and make the streets in a significant zone of their city entirely closed to fossil fuel powered vehicles by 2030.

Alongside real data provided by C40 cities, the report is based on a large amount of modelling, all of which has been aggregated up to apply to six city typologies, so the findings can only be a guide to what might be needed in any specific city. Nevertheless, in my view ‘Focussed Acceleration’ makes the best stab yet of what a successful pathway to a zero carbon city might entail.

Every city is unique and models can never provide a blueprint for action. But cities are a unique combination of universal elements and by focussing on the critical levers that can deliver a zero carbon transformation ‘Focused Acceleration’ provides a tool which mayors around the world can use to test the ambition of their climate policies and inspire greater action.