Journal of Urban Technology,2015 Routledge VoL.22,No.1,3-21,http://dx.doi.org/10.1080/10630732.2014.942092 Tayior b Francis Group Smart Cities:Definitions,Dimensions,Performance,and Initiatives Vito Albino,Umberto Berardi and Rosa Maria Dangelico ABSTRACT As the term "smart city"gains wider and wider currency,there is still con- fusion about what a smart city is,especially since several similar terms are often used interchangeably.This paper aims to clarify the meaning of the word "smart"in the 102 context of cities through an approach based on an in-depth literature review of relevant studies as well as official documents of international institutions.It also identifies the 1sn3nV main dimensions and elements characterizing a smart city.The different metrics of urban smartness are reviewed to show the need for a shared definition of what constitutes 8 a smart city,what are its features,and how it performs in comparison to traditional cities. :10 Furthermore,performance measures and initiatives in a few smart cities are identified. KEYWORDS smart city;indicators;sustainability;urban development Introduction In the last two decades,the concept of"smart city"has become more and more popular in scientific literature and international policies.To understand this concept it is important to recognize why cities are considered key elements for the future.Cities play a prime role in social and economic aspects worldwide, and have a huge impact on the environment(Mori and Christodoulou,2012). According to the United Nations Population Fund,2008 marked the year when more than 50 percent of all people,3.3 billion,lived in urban areas,a figure 五 expected to rise to 70 percent by 2050(UN,2008).In Europe,75 percent of the apeojumo population already lives in urban areas and the number is expected to reach 80 percent by 2020.The importance of urban areas as a global phenomenon is con- firmed by the diffusion of megacities of more than 20 million people in Asia, Latin America,and Africa (UN,2008).As a result,nowadays most resources are consumed in cities worldwide,contributing to their economic importance,but also to their poor environmental performance.Cities consume between 60 percent and 80 percent of energy worldwide and are responsible for large shares of GHG emissions(UN,2008).However,the lower the urban density,the more energy is consumed for electricity and transportation,as proved by the fact that COz emissions per capita drop with the increase of urban areas density (Hammer et al.,2011). Corresponding Address:Umberto Berardi,Faculty of Engineering and Architectural Science, Ryerson Universtiy,325 Church Street,Toronto,Canada.Email:uberardi@ryerson.ca C2015 The Society of Urban TechnologySmart Cities: Definitions, Dimensions, Performance, and Initiatives Vito Albino, Umberto Berardi and Rosa Maria Dangelico ABSTRACT As the term “smart city” gains wider and wider currency, there is still con￾fusion about what a smart city is, especially since several similar terms are often used interchangeably. This paper aims to clarify the meaning of the word “smart” in the context of cities through an approach based on an in-depth literature review of relevant studies as well as official documents of international institutions. It also identifies the main dimensions and elements characterizing a smart city. The different metrics of urban smartness are reviewed to show the need for a shared definition of what constitutes a smart city, what are its features, and how it performs in comparison to traditional cities. Furthermore, performance measures and initiatives in a few smart cities are identified. KEYWORDS smart city; indicators; sustainability; urban development Introduction In the last two decades, the concept of “smart city” has become more and more popular in scientific literature and international policies. To understand this concept it is important to recognize why cities are considered key elements for the future. Cities play a prime role in social and economic aspects worldwide, and have a huge impact on the environment (Mori and Christodoulou, 2012). According to the United Nations Population Fund, 2008 marked the year when more than 50 percent of all people, 3.3 billion, lived in urban areas, a figure expected to rise to 70 percent by 2050 (UN, 2008). In Europe, 75 percent of the population already lives in urban areas and the number is expected to reach 80 percent by 2020. The importance of urban areas as a global phenomenon is con- firmed by the diffusion of megacities of more than 20 million people in Asia, Latin America, and Africa (UN, 2008). As a result, nowadays most resources are consumed in cities worldwide, contributing to their economic importance, but also to their poor environmental performance. Cities consume between 60 percent and 80 percent of energy worldwide and are responsible for large shares of GHG emissions (UN, 2008). However, the lower the urban density, the more energy is consumed for electricity and transportation, as proved by the fact that CO2 emissions per capita drop with the increase of urban areas density (Hammer et al., 2011). Corresponding Address: Umberto Berardi, Faculty of Engineering and Architectural Science, Ryerson Universtiy, 325 Church Street, Toronto, Canada. Email: uberardi@ryerson.ca Journal of Urban Technology, 2015 Vol. 22, No. 1, 3–21, http://dx.doi.org/10.1080/10630732.2014.942092 # 2015 The Society of Urban Technology Downloaded by [Shanghai Jiaotong University] at 01:47 22 August 2017