In Europe, three quarters of the population lives in cities. Although they cover only a small share of the available land, cities account for 60-80% of CO2 emissions globally. While this makes cities a big contributor to the challenge of climate change, they are also key players in the solution. Efforts to reduce GHG emissions can be easier to realize in cities, since they often have multiple co-benefits: reducing air pollution, decreasing traffic congestion and improving urban health, to name a few. More importantly, with their concentration of people, money and ideas, it is in cities more than anywhere else that new solutions can be created and tested, and where the zero-carbon transformation can be accelerated.
In this context lies the opportunity of the growing decentralised grassroot social innovations, as well as the potential for the massive shifts in behaviour that can come from new markets, such as new Mobility-as-a-Service (MaaS): the joy and nuisance of electric scooters provides a recent example of this, although it has not quite yet ‘settled’ in the European urban fabric.
Further, the sharing and circular economy has the potential to truly meet the demands of city dwellers. The larger the population of a city is, the more specialised services and products are available. As Jane Jacobs stated in her now legendary book (The Death and Life of Great American Cities, 1961) , one of the reasons why people choose to live in cities is the level of choice and space for sub-cultures that they provide.
Finally, nowhere is the potential for smart and integrated technology greater than in cities, where interconnected infrastructure enables efficient urban living at scale. People have always gathered in cities for their efficiency to access resources and with increasing interconnectivity, urban systems can optimise this efficiency even further.
With this potential in our cities and with an EU ambition to become carbon neutral by 2050, there is good reason to call for ‘full steam ahead’ on decarbonisation efforts in cities. Initiatives such as the Covenant of Mayors, C40, ICLEI, Carbon Neutral Cities Alliance and others provide structured pathways and methods for cities to adopt a decarbonisation agenda. These are important accelerators as they build inspiration –as well as competition– that encourages cities to decrease emissions fast.
However, as much as we need cities to decarbonise quickly, we also need cities to become sustainable in the long-term, to be able house even more people in the coming decades and to showcase long-term resilient solutions to all the sustainability challenges that are facing them. For this reason, we need to design zero-carbon urban solutions that are resilient to several risks.
With increasing interconnectivity, smart appliances and an increase in electrification of city services, cyber and power security becomes increasingly important. Hacking of systems that manage our transportation, heating and cooling systems or other services, could become a risk. Further, the needed electrification of urban mobility and many of our buildings’ basic services, such as the locks of residential building front doors, also increase the vulnerability towards potential power blackouts. On the flipside, decentralised ‘prosumer’ type renewable energy systems proposed in urban decarbonisation strategies could help increase household or neighbourhood resilience and preparedness for crises.
In this regard, climate change mitigation and adaptation must go hand in hand in this urban transition. Climate neutral technologies need to be robust to the impacts of climate change that will face our cities in the coming decades regardless of how quickly we cut GHG emissions. Within and outside cities, the integrated nature of climate, land, energy and water systems further create feedback loops where solutions within the energy sector may jeopardise water availability or food production. Such interactions needs to be considered in urban planning and decision-making related to these resources.
Finally, any urban decarbonisation strategy must include a social equality perspective to be robust, as well as realistic: Inequalities have been rising in European cities over the past decades. Meanwhile, the transformation to a zero-carbon Europe is estimated to demand new investments of between € 175-590 billion annually, and these investment needs fall disproportionately on the private ‘end-users’, who are supposed to invest in low- or zero-carbon and/or smart appliances. This creates a twofold risk. On the one hand, if the costs of these appliances increase to a level that is unacceptable to a majority of the citizens, the transformation will fail. On the other hand, if the investments are acceptable to most but not to the socio-economically most vulnerable, this may further increase inequalities. Public intervention to mitigate these potential financing constraints is important. So is the need to balance costs and benefits in the decarbonisation transition in cities in general, ensuring that e.g. job creation and new income opportunities benefit all.
While these vulnerability aspects are important, they must not be used as arguments against rapid and ambitious urban decarbonisation. They are rather suggested ‘railings’ to help guide the journey towards what could and should be more liveable, healthy, inclusive, circular, smart and green zero-carbon cities in Europe.
By Rebecka Engström, KTH Royal Institute of Technology in Stockholm