The concept of digital twins traces its origins to product development and simulations of the behaviour of physical objects. It emerged from manufacturing and prototyping such as those conducted by NASA and Formula One racing cars. The digital object that forms the twin looks the same and behaves the same as the “real” object, and so the digital twin can provide simulations and predictions.

A digital twin presents a digital replica of a real object or process or a system and uses data from the real environment to represent, analyse, validate and simulate present and future behaviour. Typically, connecting real objects with its digital twin enables testing new scenarios or models in real time without interfering with the real objects. Using digital twins, various forms of data analysis can be performed in the digital realm and results can be visualised, e.g., predictive analysis, cause-effect analysis, or analysis of what-if scenarios, and that makes local digital twins (LDTs) of cities, regions or communities an ideal tool for awareness raising, planning and decision-making.

According to the Global Enabling Sustainability Initiative (GESI) [1], digitalization can improve: Economic development and housing, through the sharing or peer-to-peer accommodation platforms.

In this page, you can find an overview of tools that cities can utilise for creating their action plan: NetZeroPlanner, Climateview, SuperUrbanity, Kausal and others

Explains scenario-based modelling tools for evaluating mobility and energy interventions through integrated simulations of environmental and spatial impacts.

Explains city dashboards as digital tools for monitoring urban indicators such as emissions, traffic, and air quality to support data-driven decision-making.

The renovation supporting solutions can potentially support users (Facility managers, Building owners, ESCOs) in the design and selection of most appropriate building renovation actions. In modern data-driven developments, this is achieved by leveraging the real-time data coming from the actual operation of the building combined with occupants’ behaviuor- and comfort profiles. With the support of data science (i.e. AI algorithms) an alternative renovation scenarios for the selected buildings in the city can be studied. The alternative scenarios may include various use cases and examples of potential renovation actions and their comparison & ranking based on target emission measures, energy savings, costs and other parameters. There the commercial products exist in the market such as e.g. IDA-ICE. From European research side, there are projects running that aim at developing AI/Data driven applications and tools to support renovation tasks, such as, for example BEYOND, SYNERGY or MATRYCS.

Smart grid is the concept that describes the evolution of power systems to integrate and utilise techniques to adjust the flow of power to optimise the match between electricity supply and demand. The term 'smart grids' is used to define the integration of new technologies and methods, often data-driven, in existing power system infrastructure.

Describes tools and practices for documenting data ownership, governance and access rights to support trustworthy urban data ecosystems

Introduces digital participation platforms that enable citizen engagement, co-creation and feedback in urban planning and climate governance.

Describes digital systems that support disaster risk assessment, climate adaptation planning and resilience management using integrated data sources.

Agile systems development, including prototyping and sandboxes, is a method of software development that emphasizes collaboration, flexibility, and rapid iteration. This approach is based on the Agile Manifesto, which advocates for a more flexible and responsive development process that can adapt to changing requirements and customer needs. In the construction industry, Agile systems development can be used to create digital tools and solutions that support the design, construction, and operation of buildings.

The United for Smart Sustainable Cities (U4SSC) is a global initiative that provides an international platform for information exchange and partnership building to guide cities and communities in achieving the UN Sustainable Development Goals.

Public Code Management is a practice of developing and managing publicly funded software development openly. An ideal situation is to offer free software for everyone. In contrast to proprietary software development, the innovative solution is developed by public organisation with everyone able to share, explore, utilise, and improve the work. The core principle is responding to fundamental rights of individuals.

Given the exponentially increasing amount of data being generated in cities and communities by many different agencies and the fact that much of this data could be of value to other agencies, increasing numbers of local data sharing ecosystems (Local Data Space) are being set up, where many different agencies can make useful data that they are gathering available for use by other agencies.

City Platforms are a key part of any city architecture and cities and communities will each have a variety of different platforms at different layers of their overall city platform.

Interoperable Europe is an initiative of the European Commission for a reinforced interoperability policy in the public sector.

Minimal Interoperability Mechanisms (MIMs) are the minimal but sufficient capabilities needed to achieve interoperability of data, systems, and services between buyers, suppliers and regulators across governance levels around the world. Because the mechanisms are based on an inclusive list of baselines and references, they take into account the different backgrounds of cities and communities and allow cities to achieve interoperability based on a minimal common ground.

Open data models refer to the sharing of data in a freely accessible format, allowing for greater transparency, collaboration, and reuse of information. In the construction industry, open data models can be applied to building information modelling (BIM), which is a digital representation a building or infrastructure.

Building, structure and infrastructure content in cities is exchanged many ways. When software dominates in market it may be referred as ‘de facto’ standard, but technical guidelines and specifications are decided by its developers. Open standards, on the other hand, are freely available for anyone to use without any legal, technical, or financial restrictions.

IoT sensors are connected devices collecting and transmitting data over the internet. They can be monitoring environmental parameters such as temperature, humidity, air quality. Edge computing is technology doing data processing near the data source, so called at the edge network sometimes also called also fog. Together these solutions can improve performance and efficiency of environmental monitoring system because less data is transferred, and local processing reduces processing in main system e.g. in cloud.

The Predicitve Maintenance supporting tools in general aim at the facilitating predictive maintenance tasks for various large energy systems (e.g. HVAC) installed in buildings.

Building automation and control systems contribute to the energy-efficient operation of buildings of all use types. They enable the energy-efficient and cost-effective integration of local renewable energy supply technologies, as well as the management of energy storage and flexibilities to optimally balance energy demand and supply in the operation of building energy systems. The market for building automation systems provides several tested approaches and commercial solutions e.g. BEOS from Siemens, which is showcased in Seestadt Aspern Vienna. Additionally, aspects of building maintenance can be integrated in building automation systems, which allows for maintenance demand predictions that enable the cost-effective operation of buildings.

The Measuring and Monitoring services and tools may include the following parts: learning info kit, data collection sources & respective ICT technology, and tools and services to support measuring & monitoring of green and digital transitions.

There is a strong global interest on reducing CO2 emissions. Two cost-effective main routes for this are emissions trading and carbon taxes. CO2 trading platforms are digital marketplaces where businesses, governments, and individuals can buy and sell carbon allowances. It may include one or more exchanges, brokerage, and auctions for allowances. Services may be provided by private sector or government agencies. Actors purchase credits either for compliance (targets) or voluntary purposes. Carbon credits represent the right to emit one tonne of carbon dioxide or its equivalent, traded on these platforms to help meet emissions targets set by governments or international agreements and reduce greenhouse gas emissions.

There are a range of AI applications that can contribute to climate neutrality in cities, across various themes, including energy, transport and built environment.

The local data spaces policy in the construction industry refers to the creation of digital representations of a building's data in a secure and controlled environment. This includes information about the design, construction, and operation of the building, such as building plans, specifications, schedules, and energy consumption data. The purpose of this policy is to provide a centralized repository of building data that can be easily accessed and shared by all stakeholders, including designers, contractors, owners, and building occupants.

With the introduction of satellite images and geolocated data to a broad public, new opportunities are offered to city planners and governments to take informed decisions by quantitative analyses and even predictions based on these technologies. In doing so, urban phenomena, such as the relation of population demographics to current challenges of cities (as for instance, climate change in cities, crime or deprivation) can be discussed or future predictions of urban development modelled to analyse their infrastructure costs to assist cities in climate-friendly resource-efficient urban planning.

Greenhouse gas (GHG) monitoring from space is a solution that uses satellites to measure carbon dioxide (CO2), methane (CH4), nitrous oxide (N20) and ozone (O3) emissions in the atmosphere. Construction industry produces a significant portion of global GHG emissions, and buildings with their energy sources are one of largest contributors to these emissions. The technology allows to track the sources and movement of emissions.

Building Information Model (BIM) and Civil Information Model (CIM) are digital tools transforming the construction industry. BIM is a set of technologies, processes, and policies of creating and managing digital representations of a building or structure, while CIM is focused on civil infrastructure facilities and sometimes called infraBIM. These tools enable stakeholders to design, construct and operate projects in city environment more efficiently.

Decision making in the urban environment is typically performed using a scenario-based analysis. Stakeholders define a base scenario, which serves as the current situation in a city. Additionally, a reference scenario in which e.g. a road is closed can be defined to study the effects of the closure and make a comparison with the base scenario.

Predictive modelling is a crucial element for both real-time management and long-term planning in urban areas. For example, road sensor data can be used for real-time traffic management in a city, while predictions based on this data can enable decision makers to study long-term effects of interventions in a city. Typically, predictive modelling is performed for one domain in isolation, such as traffic predictions. However, for an integral view on a city it is important to combine such predictions with other domains such as air pollution, noise and behaviour of a population in a city.

The free-cooling systems are based on a simple idea: exchange indoor air with outdoor air, which allows you for conditioning a zone for free. Free cooling cannot be used alone as it depends a lot on climate conditions, so it is usually applied together with a mechanical ventilation system or air-conditioning system