In the XXI. century climate change and depletion of natural resources are recognized as the main environmental issues. Most of it is due to human activity, which also makes it mankind’s job to find solutions. Creating sustainable cities can definitely be one of them, as cities with their 75% of global CO2 emissions are key contributors to climate change. Also more than 54% of people live in urban areas, which creates the need for more habitable areas. Of course not every city is on the same level of sustainability. There are some that stand as great examples before those which need to implement significant developments. There is a need to measure cities’ sustainability and also to identify their key sectors in which they perform the worst. This could allow huge savings to be achieved.
This thesis shortly presents sustainability with all of its aspects.Then the energy-related problems are investigated and potential solutions are given. The next chapter shows that these „new” technologies are already in use in some cities, or at least the knowledge is there in form of „good-practices”. Furthermore implemented indexes and their structures are presented, which is followed by the creation of a hypothetical sustainable city index. In this new system I try to measure cities’ performances in the energy sector, also putting emphasis on their relation with the environment.