It takes three ingredients to create sustainable cities. They need to be liveable, resilient and resource efficient
Dr. Kerstin Krellenberg: “Developing existing and newly emerging cities in a way that they provide livable, resource efficient and resilient living conditions for all people is of highest importance in order to transform our world towards sustainability.
There is no single solution towards sustainability.
Creating sustainable cities is by no means an easy task. Different urban developing paths are prevailing which are framed by diverse political, institutional, economic, climatic, demographic, cultural etc. settings. This means there is no single solution towards sustainability.
I am therefore convinced that considering citizens’ behaviour, needs, fears and perceptions in urban sustainability transformations will need to take centre stage.”
What does it take to create liveable cities?
The key factors in establishing a good cycling infrastructure or rather
creating a liveable city.
Mark Wagenbuur, the cycling expert, shows by example how we can create liveable and safer cities: “Cycling cities are less polluted, less congested, people who cycle are healthier and happier. Active travel changes people’s lives and their environment for the better. Cycling infrastructure is cheap to build and cycling is cheap for the person doing it. Cycling only has advantages and lots of them.”
What does it take to for a successful energy transition?
Prof Dr. Andreas Wagner, expert for building physics states explains what is essential for a successful energy transition and why we need to focus on the building sector as well as the heating energy.
The building sector’s share of germany’s total end energy consumption is approximately 40% out of which 80% is heating energy. The maximum heating energy demand occurs during periods when solar contributions are small. Consequently, energy storage and a variety of different renewable resources are important prerequisites for a successful transition. Furthermore, we have a large existing building stock. Buildings built before 1980 consume about 90% of the energy of the whole building sector. Without stringent measures to decrease the CO2 emissions of existing buildings we will not reach our climate targets for 2050.
First, we have to more than double the refurbishment rate for buildings to significantly increase energy efficiency of the building stock. This is not only a technological, but even more an economical, political and societal challenge.
Second, different technologies for heating on the basis of renewable energies have to be pushed forward, including heat pumps (i.e. electrifying the heating sector) as well as biomass as a storable resource. Here, cities can play an important role by shifting the focus from single buildings to whole neighbourhoods for integrated energy efficiency and supply solutions.
What are building-integrated photovoltaics (BIPV) and why can they make cities more sustainable?
Dr. Björn Rau: “Building-integrated photovoltaics is the integration of electricity-generating elements into the building skin. Photovoltaic modules become also construction elements of the building and vice versa a roof, a façade, a sunblind or even a window also produces electricity directly from sunlight. BIPV generates electrical energy there, where it is consumed without any climate-damaging emissions.”
- What are the biggest challenges cities are facing? And how do we need to address them?
We need to address them transdisciplinary
Dr.Kerstin Krellenberg: “Urban areas are where more than 55% of the world population resides, which creates many challenges as well as opportunities.
Cities are highly complex and present many societal challenges, which calls for integrative perspectives and systemic considerations in order to develop feasible solutions. This again cannot be achieved within disciplinary boundaries and without considering the knowledge and interest of the many societal actors involved in urban development.
Here, inter- and transdisciplinary research can play a decisive role in bringing disciplines, actors and sectors together and to work jointly on real-world problems and transformations towards urban sustainability.”
Franziska Adams: “Studying in several large cities in Germany, USA and Denmark confronted me with urgent challenges, such as the lack of affordable housing and the dominance of cars over pedestrians/bikers. The key take-away from the Winter School for me is that sustainable development is so much more than just focusing on cars or housing, but combining several disciplines and considering state-of-the-art cultural, political and technical situations, including coincidences which are sometimes more effective than planned efforts.”
We need to embrace solutions that are already out there
Dr Björn Rau: “There is a very high potential for BIPV (e.g. Germany >30%) to contribute significantly to the energy supply of a society. Unfortunately, BIPV still does not play the role that it could do. One main reason is the missing knowledge in the group of the initial stakeholders of construction or renovation projects about potential and already technical and creative possible solutions. Another aspect is the complex world of regulatory frameworks which comes into play if solar modules meet the world of construction.
Moreover, further technical solutions have to be develop to provide cost-effective, multifunctional construction elements meeting the demands of architects and planners.”
Prof. Dr. Andreas Wagner: “Coupling building-internal and external (neighborhood) energy infrastructures offers a large potential to increase the share of renewable and decentrally generated energy on the basis of a levelized building energy efficiency standard.”
We need to know the major lever
Janina Hoffmann: “Prof. Dr. Wagner’s clever wordplay “Keine Energiewende ohne Wärmewende. Keine Wärmewende ohne warme Wände.” (No energy transition without heat energy transition. No heat energy transition without warm walls) gave me a new perspective on the challenge of the energy transition. Even though I knew that you can reduce your heating costs immensely with each degree.”
We need to drive change in cities
Sarah Scheck: “We are currently undergoing a crucial and most likely radical change referring to our economical and societal development, for instance when we look at topics such as globalization, digitalization, shift of power on a global level just to name a few. I feel the strong need of the population to exert influence on the direction of those developments in order to not lose human factor but rather take the opportunities that are there by focusing on the common good. Cities will be the places in which most people can be reached and most of those approaches and changes can be undertaken.”
Ban Ki-moon, Ex-UN General Secretary: “Our struggle towards sustainability will be won or lost in cities”
We need to act neighbourly
Sarah Hündgen: “Cities are the places we live in, the places we settle down, the places our everyday social network evolves. Thus, cities heavily impact our quality of life – maybe even more than any other single factor. This is why I believe that to “leave no one behind” in our global journey towards a sustainable future (as the SDGs claim), it is crucial to act local: on a neighbourhood and city level.”
We need to get the ball rolling
BochumBolzt: “We want to combine the great social power of soccer with environmental protection. Our Goal is the liberation of our city from all types of garbage, especially plastic waste. Our Tool – small neighbourly soccer fields!”
We need to take action
Tim Belau: “In an urban setting where buildings and roads already exist, you might think everything is set. But when people come together and build bottom-up movements a city can develop, road after road building after building. To start the transformation we need to discuss what we a livable and sustainable city looks like. Solutions are out there already, but we have to pressure people in charge to implement them also in our home towns. I want to care about my surroundings. I want to connect with my neighbours. I want to change my city because honestly there are just too many cars in Berlin.”
And action: What do you want to address in your city? What can you change in your city?