A sustainable city needs to be SMART.
In order to reach sustainability, SPECIFIC targets need to be set and met: e.g. reaching climate neutrality within a certain time frame. Those targets need to be MEASURABLE. It is not enough to just talk about sustainability and a transition. It is very important that the targets can be quantified and that results are shown. Reaching sustainability demands a lot of effort. Therefore it is important to make a time-plan and split up the final target into small steps that can be reached more easily and which can be measured. This introduces the 3rd aspect, i.e. targets need to be ATTAINABLE. When dividing the final target into smaller steps, results of the measures taken become visible one by one. It is also important to involve local stakeholders, e.g. inhabitants, local companies, governments, etc. Each step in the plan towards final sustainability can be celebrated, giving a boost to the people involved, showing that their actions result in something positive on the way to the final target. The measures need to be REALISTIC. It is good to dream about sustainability and about the transition to a sustainable city, but it will be reached by taking one step at the time. When going too quickly, without a plan to follow, problems can be created and it may become difficult to reach the final target. The approach needs to be TIMELY. It is important to develop a good plan towards a sustainable city. This means going step by step, and choosing which step/measure to take at which moment in a smart and innovative way. Thus, use what is available at a certain time and apply this measure to the best knowledge. Furthermore, try to find ways to improve these measures to bring cities to a next, sustainable level.
There are many examples and I will name a few. On the island of Samsoe in Denmark, they reached energy neutrality in 2005 (started in 1997). Some general facts: surface is about 110 km², and about 4000 inhabitants. The energy system of the island is based on wind and solar energy for electricity, biomass (straw and wood chips) and solar energy for heat and measures are taken for the fossil fuel use of the ferries and cars on the island. Güssing, Austria, is a nice example of how a complete village and region can transition from a fossil fuel based system with high costs to a system based on renewables, keeping more of the money in the region. General facts: surface is about 50 km², and about 3700 inhabitants (region 27000). They started in 1992 with the transition. Güssing has reached a 71% self-sufficiency in 2010 (100% if industry is not taken into account) and they are working on also reaching energy autarky within the Güssing-region. The energy system is based on local available biomass (wood, grass, rapeseed), via a CHP-plant and district heating, and solar energy. I will name one other example: the work that is done in the city of Wageningen in The Netherlands to transition to a climate neutral city by 2030. Wageningen has about 36000 inhabitants on about 32 km². In this initiative the municipality involves also local stakeholders like inhabitants and companies. The targets are: 25% local renewable production, 50% energy saving, and 25% import of renewable energy. Many more examples can be mentioned.
Furthermore, a SMART sustainable city needs to include the following aspects:
A sustainable city needs to be SUSTAINABLE. When taking a measure, this has to be done in a considered, clever way. A measure has to be ecological, economical and socio-cultural. This means keeping in mind also the future perspective: think about here and there, current and future generations (UN-Brundtland commission 1987, definition Sustainable Development). A sustainable city needs to be MULTI-functional/disciplinary. It is important to use the mixture of functions to find the most efficient and effective solutions for problems in the city. The multi-functionality needs to be seen as an opportunity and not as a problem. Another important aspect is AFFLUENCE. This means that people need to be able to live good and in the way they want, but they have to be aware of the consequences of their actions. A sustainable city has to inform its inhabitants about smarter ways to reach their targets, better for both the environment and the city. Those measures have to improve the quality of life in the city. A sustainable city needs to be RENEWABLE. This is/seems logic, meaning that the use of resources should be renewable. The measures taken need to be renewable or from residual origin. It is important to divert away from the old way of thinking: it is not possible anymore to use fossil fuels/resources as we currently do and think that we can compensate for the emissions and other negative effects. A last aspect for a sustainable city is the TECHNOLOGICAL one. This implies using the available knowledge and not always throw it away immediately because it seems not worthwhile or too expensive. Those new methodologies/measures need to be given time to develop. The technologies for fossil fuel use did not come out of the blue either and needed a lot of support as well.
The following figures show results of a study applied to a municipality in the south of The Netherlands, Kerkrade.
Fig. 1: Energy demand for different urban functions
Fig. 2: Energy supply potential for the studied district (solar: PV/solar boilers; hydrogen production demands electricity which is supplied by extra wind turbines).
The results are based on research described by the author in a published paper. Available by author on request. Reports on Samsoe, Güssing or Wageningen on which results are based, on request by author.