Humankind is now, for better or worse, an urban species. More than half the human population lives in cities, a number expected to increase to 80% by 2050. While cities occupy 2% of land, they use 72% of all energy and are responsible for 73% of all pollution. This means that the future of humanity is tied intimately to how we manage and develop cities.
The classical view of city planning and management is one of linear consumption, where resources come in and waste comes out. This has contributed significantly to excessive energy use and pollution.
Luckily, a new vision is emerging. Modern physicists and city planners are now beginning to argue that rather than viewing the city as a conveyor belt, it should be viewed as an organism.
Organisms have a metabolism that converts energy and resources into the nutrients and substances that they need. The same is the case for cities. They also take in energy, raw materials, and water and convert them into heating, entertainment, houses, and pretty much everything we associate with living in a city. Just like a person’s metabolism, a city’s metabolism determines how well resources are used and stored, which in turn impacts a city’s health and the surrounding environment.
Consequently, the metabolism of cities is an important area of focus when it comes to optimizing the use of energy, water, and raw materials. By better understanding how cities work, it becomes possible to apply insights from the circular economy, which focuses on reusing and re-purposing waste products as resources.
Just like a person’s metabolism, a city’s metabolism determines how well resources are used and stored, which in turn impacts a city’s health and the surrounding environment.
In a 2007 academic article “The Changing Metabolism of Cities”, Christopher Kennedy and collaborators define urban metabolism as “the sum total of the technical and socio-economic processes that occur in cities, resulting in growth, production of energy and elimination of waste.”
But, as Kennedy concludes in his article, which reviews information from six cities, there is currently not enough data available to build an adequate understanding of just how a city’s metabolism works.
This is what the Metabolism of Cities project aims to correct with the Metabolism of Cities Data Hub. Metabolism of Cities is an open-source project that helps promote the study and use of circular economy principles.
Cofounder and circular economy researcher Aristide Athanassiadis explains, “With Metabolism of Cities we hope to accelerate the implementation of urban metabolism principles in policy and practice through our community-led online and open-source platform. With that, we hope to drastically and systemically reduce the environmental impacts of cities in a socially just and context-specific way.”
The organization’s Data Hub is an extension of this work, operating as a structure for compiling the data points needed to facilitate comparisons and insights from cities around the world. While a lot of data exists in various cities’ open data sites (there are 48 cities with open data portals in the United States alone and more than 130,000 datasets in the European Union) it is still ad hoc what ends up there.
Even if information for studying the metabolism of cities is available as open data, it is frequently like finding a needle in a haystack. Through a common data structure, the Data Hub ensures that the right data can be sourced. Volunteers help locate and curate data that ends up in a consolidated global data set.
The hub currently contains data from 69 cities around the world. Some cities like Brussels have almost 100 datasets in the hub on topics varying from social housing stock to particle pollution and charging stations for cars. Datasets can be viewed as graphs on the site which are also available for visitors to download.
In addition to the Data Hub, the Metabolism of Cities project also focuses on producing educational material to help policymakers and other practitioners apply insights from the circular economy. Athanassiadis explains that one goal of the project is to make the topic more readily accessible to a broader audience: “Most initiatives working in our field are either consultants (so they have little interest in making free tools and developing a community) or academics (whose work can be full of jargon and difficult to use). We try to bridge this gap and create a digital common.”
Part of this digital common includes six online courses the project uses to educate people on the benefits, principles, and practices of circular economics.
“Most initiatives working in our field are either consultants (so they have little interest in making free tools and developing a community) or academics (whose work can be full of jargon and difficult to use). We try to bridge this gap and create a digital common.”- Aristide Athanassiadis
Anyone is able to access the courses and participate in a number of different tasks listed on the site. They need programmers, but also designers, social media managers, photographers, and people who can help with fundraising. One of the biggest benefits is that everyone interested in helping cities become more sustainable and equitable are able to join the growing community.
Though several cities have started to develop more circular approaches to handling waste and more research is being done on the topic than ever, the Metabolism of Cities project continues to occupy a unique position.
“We are one, if not the only, website focusing on urban metabolism,” says Athanassiadis. “This academic topic is not very well known and is very consolidated. So, we’re trying to make it accessible, collaborative, contributive, free, and most importantly retain a scientific rigor.”
Certainly, courses and data are a great place to start, but without practical implementation, theory becomes unusable. The true hope for the Data Hub is that it, and the Metabolism of Cities Project as a whole, will serve as a foundational resource, a sort of “first step” for individuals interested in establishing meaningful action for urban communities. Once first understood, these resources can then be applied, expectantly resulting in tangible improvements to these cities’ material conditions.