Cities all over the world are entering a new era. The concept of smart cities that encourages the digital transformation of many city sectors, has been gaining popularity globally. A smart city is defined as a city which merges traditional infrastructure with Information and Communication Technologies (ICT) in order to promote innovation and provide useful services with the use of new digital technologies (Batty et al., 2012)[1]. Accessibility and use of ICT infrastructures can have a positive impact on urban performance and consequently urban wealth (Caragliu et al., 2011)[2], since they can exploit information from big volumes of real-time data and then use this data to provide solutions in different city sectors (Kim et al., 2017)[3].

Digital technologies constitute the core of a smart city. Technologies, such as the Internet of Things (IoT), can become intelligent assets to smart cities by enabling remote monitoring, managing and control of smart devices. IoT suggests the installation of sensors in smart cities and their connection to the Internet to provide experts the ability to recognize, locate, track and monitor various factors and consequently acquire all the information needed to make right management calls4.

Trends and opportunities

Nowadays, the concept of smart cities still remains, mainly, at a theoretical level4. Only a few developed countries have made actual progress towards digitalisation. For example, the Smart Nation Program (SNP) of Singapore has been making an effort to utilise sensor data and incorporate different technologies to connect communities online. Another approach towards sustainability is the utilisation and integration of renewable energy resources.

Due to the large volume of data that are constantly generated in smart cities, it is imperative to find and apply appropriate methods to process conventional data. This can be achieved by utilising Big Data Analytics, but only a few studies have been conducted over this matter and most have not been experimented in real world scenarios. In addition, the collection of personal data constitutes a main concern nowadays, and one that must be addressed. It is common for citizens to avoid using ICT platforms, which are key features of smart cities, because they are concerned about how their sensitive data is used. Implementation of security measurements when it comes to this kind of data is an essential necessity.

Finally, smart cities use a wide variety of digital devices in order to offer reliable services at any time of the day. These components need to be able to communicate with each other despite all the incompatibilities that may exist in operational platforms and communication technologies. Solutions aiming to bridge the gap between these heterogeneous devices constitute another key area for research.

Examples of IoT implementations in smart cities

Many regions in the world have already turned their attention towards the concept of smart cities. A great amount of smart city solutions has been implemented, with most solutions focusing on extremely important aspects of everyday life such as waste management, traffic control and air quality.

Building a smart city has many benefits for a country and its population. It can enhance citizen and government engagement, since the former can have access to a variety of user-friendly digital services, as well as governmental data and live-streamed city official meetings which can help in increasing civic engagement and build trust in city officials. Smart cities also aim to reduce the environmental footprint of a city by building energy-efficient buildings, using air-quality sensors, and looking at renewable energy resources. This can have a positive impact on citizens’ health, since air quality, and environmental degradation in general, is known to harm human health. In addition, access to a variety of data can contribute to the right decision-making in different city sectors. Finally, IoT solutions can improve waste and water management by providing tools aiming to reduce the unnecessary exploitation of the limited supply of natural resources.

Challenges of digitalisation

Even though the digitalisation of cities has many benefits for both the city and its population, there are a few challenges that should be addressed and surpassed to successfully transform a city into a smart city. Some of these challenges are the following[4]:

  • Design and maintenance cost, i.e. the financial capital used for designing the smart city and complete daily operational and maintenance tasks
  • Heterogeneity in smart city architecture, i.e. smart cities depend on their ability to integrate and operate at the same time with data from various sources (e.g. sensors, devices, etc.)
  • Collection of citizen data from the urban network
  • Constant generation of extremely large data volumes, which may disrupt operations in smart cities
  • Finding renewable energy resources to reduce carbon footprint and utilise the already limited resources in an efficient way to preserve the urban environment and ensure sustainability
  • Finding solutions regarding waste management to minimise environmental pollution and land filling
  • Implementation of effective failure recovery mechanisms when failures occur (e.g. due to natural disasters).


The role of cities, to protect human health and biodiversity in urban areas, to improve the integrated ecosystems, and to contribute to the reduction of greenhouse gas emissions, is significant and this is also recognized by the European Green Deal. This requires an urban digital ecosystem that allows creating value-added services, and simulations of policy choices that can be accessed by decision-makers across cities and communities in the EU. Cities need to have insights, actionable evidence on the state of the environment and interactions between the economy, society and the environment.[5]

All in all, the concept of smart cities is starting to become more popular nowadays and will definitely play an essential role towards sustainability. ICT, which is a main component of smart cities, can provide solutions that are desperately needed to solve problems concerning different city sectors, as well as the environment. The main goal of smart cities should be to improve services and solutions regarding the most prevailing urban issues.



[1] Batty, M., Axhausen, K.W., Giannotti, F. et al. Smart cities of the future. Eur. Phys. J. Spec. Top. 214, 481–518 (2012).

[2] Caragliu A., Del Bo Ch, Nijkamp P., Smart Cities in Europe (2011),

[3] Kim T., Ramos C., Mohammed S., Smart City and IoT, Future Generation Computer Systems, Volume 76 (2017), Pages 159-162,

[4] Silva B. N., Khan M., Han K., Towards sustainable smart cities: A review of trends, architectures, components, and open challenges in smart cities (2018), Sustainable Cities and Society, Volume 38, Pages 697-713,

[5] Artificial Intelligence, digital solutions, smart cities & the Green Deal

Featured image: Future Connected City: 2086 © JCT 600/Flickr link to the original article: here