- Smart cities combine physical infrastructure, advanced digital technologies, and human and social capital to improve quality of life and urban sustainability.
- Sensor networks, big data and digital twins enable more efficient management of energy, mobility, water and waste, supporting data-driven urban decisions.
- Spain and the European Union are promoting specific plans, calls for proposals and tools to finance smart projects and create collaborative ecosystems between cities, companies and citizens.
- The future of smart cities lies in balancing technological innovation, citizen participation and social justice, avoiding technological dependencies and prioritizing inclusive development.
The smart cities They have become one of the key concepts when we talk about how we will live in the coming decades. Far from being just a marketing slogan, they combine technology, urban planning, and new forms of governance to make urban centers more sustainable, efficient, and pleasant for their inhabitants.
In practice, a smart city is a city that uses data, sensors and digital infrastructure to make better decisions: from when to turn on streetlights to how to reorganize bus routes or where to place charging points for electric vehicles. All this, without forgetting the key role of human capital, social cohesion, and the environment, because if there are only cables and screens, but it doesn't improve people's lives, we're not really looking at a smart city.
What exactly is a smart city and where did the concept come from?
The term smart city It appears to describe urban environments where physical infrastructure (transport, energy, water, buildings) is combined with advanced digital infrastructure (communication networks, sensors, data platforms) and strong social and environmental capital. The idea is that the city functions almost like a large ecosystem, where all subsystems are interconnected and can be optimized through information.
In Europe, institutions such as the European Union, the IDB, the OECD or Eurostat They have been refining this concept to differentiate it from older terms like "digital city" or "planned city." It's not just about having fiber optics or Wi-Fi everywhere, but about integrating technology with urban policies that reduce emissions, improve air quality, promote innovation, and encourage citizen participation in decision-making.
Authors such as Rudolf Giffinger propose that a city is considered smart when it excels in six major dimensions: economy, mobility, environment, population, lifestyle and governanceEach dimension relates to classic theories on regional competitiveness, transport, human and social capital, quality of life, and democratic participation.
Other experts, such as Jean Bouinot or Fadela Amara, focus on the capacity of these cities to attract and retain highly qualified talentDigitizing public services, creating quality employment and providing efficient transport infrastructure, solid health and education, as well as good leisure and housing conditions.
From a more practical perspective, a smart city is usually defined as one that optimally manages resources and energy To improve quality of life and the environment by integrating technical, social, political, and functional aspects. Important: the "smart" label is not static; it demands continuous improvement, renewing technological solutions and management models, without a fixed final goal.
Basic pillars of a smart city: technology, people and environment
One of the biggest misunderstandings is thinking that a smart city is only built with sensors, big data and artificial intelligenceICT infrastructure is fundamental (fiber optics, 5G, data networks, cloud services, e-government platforms), but by itself it does not make a city smart.
The most comprehensive definitions emphasize the role of human and social capitalEducation, training, innovation capacity, and collaborative networks among citizens, businesses, universities, and government agencies are key. Studies show that cities with a higher percentage of skilled workers are the fastest growing and best adapted to economic and technological challenges.
Another pillar is the urban environmentThe smart city is clearly different from the congested and polluted city that forces people to lose hours in traffic jams and endure high levels of noise and air pollution. Here, energy efficiency policies, the promotion of renewable energy, advanced water management, and waste reduction come into play, along with urban planning that prioritizes green spaces, sustainable mobility, and sustainable buildings.
Within this framework, IATE and other European initiatives have set goals such as reduce greenhouse gas emissions by more than 20%.Increase the use of renewable energy by 20% and improve energy efficiency in final consumption by 20%, using 2010 as a baseline. These figures serve as a guide for aligning smart city projects with the European Green Deal and other climate strategies. Furthermore, models such as the circular economy to reduce waste and close material cycles.
Finally, the smart city seeks a balance between economic, institutional, and citizen interests, promoting a open, transparent and participatory governancewhere data and digital tools are put at the service of citizen deliberation, not just administrative efficiency.
Interactive relationship, space monitoring and new forms of cooperation
A study conducted in France by Markess International in 2012 on 130 local entities identified three key features of the smart cities and territories which remain fully in force.
The first is the interactive and mobile relationship between usersCitizens are both major consumers and producers of information: they consult data on traffic, energy consumption, public services, and events, and at the same time generate content on social media, blogs, and municipal apps. This social layer includes opinions, assessments, and shared knowledge in a Wikipedia-like fashion, and fosters co-responsibility in service management.
The second feature is the optimized monitoring of urban space through control centers that connect objects, sensors, and actors via high-capacity telecommunications networks. Thanks to a diversified network of sensors and service nodes, information is collected and distributed in real time, facilitating governance, the analysis of critical situations, the adaptation of resources to needs, and budgetary control to seek efficiencies.
The third element points to development of new forms of cooperation already models of innovation governanceSmart cities promote cross-sector projects that overcome traditional administrative rigidity, creating alliances between levels of government (local, regional, national, and even international) and private actors (telecoms, energy companies, transport companies, technology companies, construction companies, SMEs, consumer associations). This collaboration opens the door to models such as the sharing of services and innovations that would not emerge from isolated silos.
Looking at the whole picture, a city is truly smart when social investment, human capital, communications and infrastructure They align with sustainable economic development and responsible use of natural resources, with strong citizen participation throughout the process.
Key dimensions: economy, mobility, environment and urban life
Following Giffinger's proposal, the six dimensions tools that allow us to classify and compare smart cities are a good compass to understand why some cities advance faster than others.
In the field of economyThe smart city focuses on knowledge-intensive sectors, creative industries, and high technology. Clusters and business parks with advanced services are being promoted, such as the smart parks in Kochi, Malta, and Dubai, designed to attract investment and global companies.
La mobility This is another key area: intelligent transport systems, dynamic traffic management, integration of electric vehicles, shared mobility platforms, flexible on-demand tolling, and policies to reduce traffic congestion (cars circling looking for parking). All of this contributes to faster journeys, less pollution, and less noise, complemented by measures of vial education to improve safety and coexistence on public roads.
El the environment This is reinforced by projects for measuring and controlling pollution (CO2, ozone, noise, water quality), advanced waste management, and efficient public lighting. Initiatives such as SmartSantander or Ohio's sensor-equipped road projects demonstrate how a real-time sensor network allows for the creation of dynamic maps to make better-informed decisions.
In the field of inhabitants and way of lifeSocial cohesion, security, the quality of health and education services, and citizens' ability to participate in public life are all valued. Attention is also paid to... energy efficiency in homes and in public buildings to reduce costs and improve resident comfort. Studies such as the IESE Cities in Motion Index incorporate dimensions such as human capital, governance, urban planning, international projection, and economics, generating a fairly complete picture of urban “intelligence.”
Technologies and sensor networks at the service of the city
From a technological point of view, a smart city is a highly complex eco-sustainable systemwhere multiple subsystems (energy, water, transport, security, waste, social services) are interconnected. One of the most relevant technical components is the wireless sensor network or network of captors.
These networks deploy thousands of devices that They measure parameters in real time: air quality, noise levels, radiation, humidity, parking lot occupancy, condition of garbage containers, presence of water leaks, traffic on streets and highways, and even variables linked to citizen security or extreme weather phenomena.
With this information it is possible, for example, adjust park irrigation Depending on actual need, lighting intensity can be adjusted, waste collection routes optimized, or parking fees regulated to reduce congestion. For citizens, mobile applications allow them to receive alerts when air quality deteriorates, know the real-time arrival time of public transport, or locate nearby available parking spaces.
The case of SmartSantander, with more than a thousand sensors deployed, is often cited as an example of how a medium-sized city can become a urban innovation labtesting solutions that can then be scaled to other cities.
However, the mass adoption of these technologies is not without its challenges. risks and criticismsFrom the potential reliance on "turnkey" solutions from large global providers to concerns about privacy, data security, or a lack of adaptation to specific local contexts.
Governance, data and public policies in smart cities
One key difference lies in how the data generated by all these systems is used. Simply collecting information is not enough: it's essential to integrate it into urban planning and daily management of public services. Organizations such as the OECD and Eurostat, through the Oslo Manual and other indicator frameworks, have developed tools to measure urban innovation and performance, supporting research and evidence-based decision-making.
At the local and regional scale, it is observed that the communications infrastructure It acts as a bridge to better economic and social outcomes, but only when combined with management capacity and strategic vision. Hence the frequent discussion of smart urban and regional planning and innovation management applied to cities.
In this context, numerous initiatives have emerged: international forums and projects, such as the Intelligent Community Forum, university research projects (MIT Smart Cities, URENIO in Thessaloniki), platforms for exchanging experiences and international congresses such as Smart City Expo World Congress in Barcelona or Metropolitan Solutions in Berlin.
In parallel, large technology companies (IBM, Siemens, Oracle, Schneider Electric, among others) and companies specializing in urban solutions offer platforms for manage everything in a “smart” wayFrom energy and security to transportation and e-government, this opens up opportunities but also fuels the debate about the commodification of urban space and technological dependence.
The most frequently cited criticisms warn of the risk of over-prioritizing the strategic interests of large companies, neglecting alternative models of urban development that place more emphasis on social justice, grassroots participation, or long-term community resilience.
International examples of smart cities and outstanding projects
The global map of smart cities is becoming increasingly broad and diverse. In the Middle East, Masdar in Abu Dhabi It is conceived as an experimental eco-city, highly energy efficient, while in the United Arab Emirates projects such as Dubai Smart City and Dubai Internet City have been promoted, which act as technological free zones for multinationals in the digital sector.
In Europe, the metropolitan area of Lyon It promotes a smart city strategy linked to economic development; Amsterdam is developing multiple projects under the Amsterdam Smart City brand, in collaboration with universities such as Wageningen and MIT; and cities such as Angoulême, Besançon, Vigo or Issy-les-Moulineaux are experimenting with smart urban networks focused on energy, service management and participation.
Other examples are the Campus of the University of Lille such as smart grid lab, Cairo Smart Village in Egypt, or e-government initiatives like Edinburgh's, focused on modernizing digital public services in partnership with global providers.
Outside of Europe, notable projects include Kochi Smart City in India, Malta Smart City as a business hub, and the Yokohama Smart City Project in Japan, aimed at reducing CO2 emissions through new energy infrastructure. In Latin America, cities such as Medellín, Curitiba, Buenos Aires, Santiago, and Guadalajara have made progress in Smart mobility, security and urban data, with support from entities such as the IDB and Ibero-American centers for strategic urban development.
In addition to specific urban projects, there is a whole constellation of events, trade fairs and professional communities that support this ecosystem: international associations of urban planners, networks of local governments for sustainability (ICLEI), United Nations initiatives such as UN-Habitat, specialized journals and thematic working groups on mobility, energy, planning and digital governance.
Spain as a leader in smart cities: plans, funding and specific cases
Spain has strongly embraced the concept of smart cities, to the point of becoming a European leader in sustainable urban mobility and digital managementThe National Smart Cities Plan, promoted by the Ministry for Digital Transformation and Public Administration, aims to strengthen the local technology industry and help municipalities in their transformation processes.
This plan is structured through several calls for proposals managed by Red.es: one first call for Smart Cities in 2014, endowed with 15 million euros and aimed at municipalities with more than 20.000 inhabitants in Andalusia, Castilla-La Mancha and Extremadura; a second call in 2015 with an initial budget of 48 million, later expanded to 63 million and open to all autonomous communities; and a specific call for Smart Islands, focused on island territories such as the Balearic and Canary Islands, with more than 19 million in total.
The funded projects include e-government platformsTraffic and energy management systems, citizen participation tools, open data, and ICT infrastructure to improve services such as transport, tourism, security, and environmental management. Co-financing with the ERDF and contributions from local authorities (between 30% and 40% in many cases) have enabled significant investments across the country.
In parallel, the Spanish Network of Smart Cities It brings together dozens of municipalities that share best practices, develop joint projects, organize conferences, and promote common standards. Initiatives such as "My Smart City," which traveled through 30 Spanish cities in an electric vehicle analyzing their level of smart city development, have helped to highlight these advances.
In strictly technical terms, the country also stands out for its deployment of smart electricity meters by CFE in Mexico (more than 7,5 million devices) and by initiatives from companies that offer solutions for smart parking, container filling sensors or urban management platforms, demonstrating that the Iberian and Latin American business fabric is very active in this field.
Prominent Spanish cities: Barcelona, Madrid, Valencia, Seville and Malaga
Several international rankings and sector studies place Spain among the countries with improved urban mobility and public transportAnd some cities particularly shine for their smart strategies.
Barcelona It is probably the best-known example: it was named the world's best smart city in 2015 by Juniper Research and hosts the Smart City Expo World Congress every year. Its strategy includes an extensive network of bike lanes, public transport with hybrid and electric vehicles, a progressive expansion of charging points, environmental sensors to measure noise, pollution, temperature and humidity, and intelligent parking systems.
The city has also implemented energy-efficient LED lightingVacuum waste collection systems that reduce odors and noise pollution, and an ambitious urban mobility plan that continues to introduce electric vehicle and shared mobility solutions. Mobility apps like Meep help integrate different modes of transport into a single digital environment for the user.
MadridFor its part, Madrid stands out for its anti-pollution protocol, the creation of low-emission zones such as Madrid Distrito Centro, 100% electric bus fleets on certain lines, and a citizen service platform that allows users to report incidents in real time from their mobile phones. It has also made significant progress in administrative digitization and electronic participationto the point of receiving international recognition, for example, from the United Nations.
Valencia has made a strong bet on centralize and open information Generated by the city council and by systems deployed throughout the city, it features smart lighting, noise control mechanisms, environmental sensors, and cleaning vehicles equipped to optimize waste collection. Furthermore, it has hosted conferences of the Spanish Network of Smart Cities, solidifying its role as a key hub in Spain.
Seville It has developed innovative projects related to the management of large events, such as crowd control during Holy Week using ultra-high-definition cameras, artificial intelligence algorithms, GPS, and adjustable lighting systems. The city is also working on Energy savings in buildings and public spaces and in the transformation of Isla de la Cartuja into an open, digital, renewable and self-sufficient urban ecosystem by 2025.
Malaga It has become a benchmark for integrating renewable energy into its electricity grid, introducing digital meters, and installing LED lighting in much of its public lighting. Thanks to these measures, it has achieved drastic reductions in energy consumption and CO2 emissions, aligning itself with the classic smart city objectives of efficiency and sustainability.
European Union initiatives: digital twins, CitiVERSE and data spaces
The European Commission is strengthening its role in supporting smart cities and communities with concrete tools. One of the most relevant is the EU toolkit for local digital twins, a kind of reusable resource box with reference architectures, open standards and technical specifications so that cities of any size can build digital replicas of their territory.
These digital twins allow simulate urban scenariosWhat would happen if the direction of traffic on an avenue were changed, a new neighborhood were built, the bus network were modified, or a low-emission zone were implemented? Thanks to artificial intelligence, cities can anticipate the effects on traffic, pollution, energy, and public health, reducing the risk of counterproductive urban planning decisions.
The Commission is also promoting a public procurement support service Specifically designed for municipalities in the early stages of their digital transformation, this "city journey" guides local governments in assessing their digital maturity, defining a transformation plan, and acquiring the necessary services to build digital platforms and future digital twins.
Another key line is the European Data Space for Smart and Sustainable Cities and Communitieswhich aims to create an interoperable and secure environment where the public and private sectors can share urban data that is currently fragmented. The idea is to facilitate collaboration, harmonize standards, and enable innovative solutions focused on the dual green and digital transitions.
To coordinate and scale these multinational projects, the EU has designed the European Digital Infrastructure Consortium (EDIC)This initiative, which will connect local digital twins across Europe, managing shared digital infrastructures, also proposes an immersive virtual and augmented reality environment for citizens and planners to visually and collaboratively explore different urban futures.
European communities, networks and programs for smart cities
European technical tools are complemented by a series of collaborative networks and movementsThe Smart Communities Network brings together representative organizations of cities and municipalities from the 27 Member States, to support especially localities that are beginning their digital transformation and need references and support.
The motion Living-in.EU It functions as a city-led platform where local and regional governments cooperate on social challenges using open and interoperable digital solutions. This community fosters the exchange of best practices and helps prevent each city council from "reinventing the wheel" on its own.
El Digital Europe Programme (DIGITAL) It provides funding for many of these initiatives, although most resources must come from national budgets, cohesion funds, or the Recovery and Resilience Facility. This financial framework is key to ensuring that pilot projects become large-scale policies and do not remain mere demonstrators.
Furthermore, the EU promotes conferences, working groups and transnational cooperation projects (such as some developed under the Interreg umbrella) that explore topics such as clean mobility, energy efficiency, climatic resilience or social inclusion from the perspective of the smart city.
All of this creates an ecosystem in which local authorities, researchers, businesses and citizens They can interact and co-create solutions, reinforcing the idea that a smart city is not decreed from above, but built by everyone.
Challenges, criticisms and future of smart cities
Despite the enthusiasm generated by the concept, smart cities face significant criticisms and challengesOne of the main warnings is that the fascination with high technology can lead to neglecting simpler but effective urban development alternatives, such as affordable housing policies, support for local businesses, or improvements to public spaces without the need for sensors on every corner.
Another concern focuses on the potential negative effects of massively deploying technological infrastructure Networking without properly assessing its social, economic, and environmental impacts. Dependence on large providers that sell closed, "ready-to-use" packages can generate compatibility problems, a lack of local control over data, and even public backlash if the population perceives intrusion or a loss of privacy.
The excessive emphasis on the city is also criticized. business spacewhere the priority seems to be attracting investment and improving competitiveness indicators, relegating issues of equity, diversity, or long-term resilience to the background. Development models based on highly mobile capital may work in the short term but generate structural vulnerabilities.
At the same time, the rise of video surveillance, mobility monitoring, and continuous measurement of urban behavior raises delicate debates about civil liberties and ethical use of dataThat is why many experts are calling for clear data governance frameworks, algorithmic transparency, impact assessment, and genuine citizen participation in the design of these solutions.
Nevertheless, the global trend indicates that cities will continue to deepen their integration of ICT, human capital, and environmental sustainability to address challenges such as climate change, mass urbanization, population aging, and social inequalities. The key will be ensuring that this urban intelligence is inclusive, democratic and people-centeredand not only in technical efficiency or technological brilliance.
Taken together, smart cities already form a kind of global laboratory where new ways of governing, moving, producing and living together are being tested; the great challenge is that all this technological and innovative deployment truly translates into more livable, fair and sustainable cities, capable of improving the daily lives of those who live in them and not just the image they project to the outside world.
