GIS-3D Platform to Help Decision Making for Energy Rehabilitation in Urban Environments

One of the main current challenges of European cities is to become energy self-sufficient entities. One of the vectors for this challenge is to improve the energy efficiency of the buildings and to promote the generation of renewable energies in the urban environment. The article describes a tool based on GIS-3D technologies to support the identification of the energy rehabilitation potential of neighbourhoods based on the introduction of renewable energies. The platform is based on a urban 3D model that collects the geometry of buildings, together with relevant information for the identification of rehabilitation opportunities (e.g. surfaces, heights, orientations and slopes). The project includes the generation of a cloud-based repository, which incorporates active and passive innovative solutions with metrics that allow the comparison of the solutions and the applicability of them to the real environment. The identification of rehabilitation opportunities combines information resulting from the diagnosis of the current energy performance of the district's buildings with the potential for renewable generation in the area. A multicriteria analysis process facilitates the identification of the most appropriate rehabilitation solutions for the analysed environment based on different criteria as energy, cost or applicability. The result can be visualized through a web tool that combines 2D and 3D information, with comparative information in a quantitative and geo-referenced manner. The flexibility of the architecture allows the application of the same approach to different urban challenges as the application of energy conservation measures to protected historic urban areas.The work of this paper has been done as part of the projects RE3D “Energy Rehabilitation in 3D” and RE2H “Energy Retrofitting of Historic Districts”, both partially funded by Basque Government, with references ZL-2017/00998 and ZL-2017/00981 respectively

A continuous deployment-based approach for the collaborative creation, maintenance, testing and deployment of CityGML models

Georeferenced 3D models are an increasingly common choice to store and display urban data in many application areas. CityGML is an open and standardized data model, and exchange format that provides common semantics for 3D city entities and their relations and one of the most common options for this kind of information. Currently, creating and maintaining CityGML models is costly and difficult. This is in part because both the creation of the geometries and the semantic annotation can be complex processes that require at least some manual work. In fact, many publicly available CityGML models have errors. This paper proposes a method to facilitate the regular maintenance of correct city models in CityGML. This method is based on the continuous deployment strategy and tools used in software development, but adapted to the problem of creating, maintaining and deploying CityGML models, even when several people are working on them at the same time. The method requires designing and implementing CityGML deployment pipelines. These pipelines are automatic implementations of the process of building, testing and deploying CityGML models. These pipelines must be run by the maintainers of the models when they make changes that are intended to be shared with others. The pipelines execute increasingly complex automatic tests in order to detect errors as soon as possible, and can even automate the deployment step, where the CityGML models are made available to their end users. In order to demonstrate the feasibility of this method, and as an example of its application, a CityGML deployment pipeline has been developed for an example scenario where three actors maintain the same city model. This scenario is representative of the kind of problems that this method intends to solve, and it is based on real work in progress. The main benefits of this method are the automation of model testing, every change to the model is tested in a repeatable way; the automation of the model deployment, every change to the model can reach its end users as fast as possible; the systematic approach to integrating changes made by different people working together on the models, including the possibility of keeping parallel versions with a common core; an automatic record of every change made to the models (who did what and when) and the possibility of undoing some of those changes at any time.This work was supported by the Optimised Energy Efficient Design Platform for Refurbishment at District Level (OptEEmAL) project, Grant Agreement Number 680676, 2015-2019, as part of the European Union’s Horizon 2020 research and innovation programme

Towards Smarter Management of Overtourism in Historic Centres Through Visitor-Flow Monitoring

Historic centres are highly regarded destinations for watching and even participating in diverse and unique forms of cultural expression. Cultural tourism, according to the World Tourism Organization (UNWTO), is an important and consolidated tourism sector and its strong growth is expected to continue over the coming years. Tourism, the much dreamt of redeemer for historic centres, also represents one of the main threats to heritage conservation: visitors can dynamize an economy, yet the rapid growth of tourism often has negative effects on both built heritage and the lives of local inhabitants. Knowledge of occupancy levels and flows of visiting tourists is key to the efficient management of tourism; the new technologies—the Internet of Things (IoT), big data, and geographic information systems (GIS)—when combined in interconnected networks represent a qualitative leap forward, compared to traditional methods of estimating locations and flows. A methodology is described in this paper for the management of tourism flows that is designed to promote sustainable tourism in historic centres through intelligent support mechanisms. As part of the Smart Heritage City (SHCITY) project, a collection system for visitors is developed. Following data collection via monitoring equipment, the analysis of a set of quantitative indicators yields information that can then be used to analyse visitor flows; enabling city managers to make management decisions when the tourism-carrying capacity is exceeded and gives way to overtourism.Funded by the Interreg Sudoe Programme of the European Regional Development Funds (ERDF

The Application of LiDAR Data for the Solar Potential Analysis Based on Urban 3D Model

Solar maps are becoming a popular resource and are available via the web to help plan investments for the benefits of renewable energy. These maps are especially useful when the results have high accuracy. LiDAR technology currently offers high-resolution data sources that are very suitable for obtaining an urban 3D geometry with high precision. Three-dimensional visualization also offers a more accurate and intuitive perspective of reality than 2D maps. This paper presents a new method for the calculation and visualization of the solar potential of building roofs on an urban 3D model, based on LiDAR data. The paper describes the proposed methodology to (1) calculate the solar potential, (2) generate an urban 3D model, (3) semantize the urban 3D model with different existing and calculated data, and (4) visualize the urban 3D model in a 3D web environment. The urban 3D model is based on the CityGML standard, which offers the ability to consistently combine geometry and semantics and enable the integration of different levels (building and city) in a continuous model. The paper presents the workflow and results of application to the city of Vitoria-Gasteiz in Spain. This paper also shows the potential use of LiDAR data in different domains that can be connected using different technologies and different scales.The European Union’s Horizon 2020 research and innovation program under grant agreement No 691883, SMARTENCITY supported and funded this study

Multiscale building modelling and energy simulation support tools

Building and district modelling (BIM, CityGML…) are key technologies for the deployment of energy efficiency strategies at building and district level, from the initial stages of planning and design to the operation and maintenance ones. These technologies allow satisfying the interoperability requirements that fa-cilitate the cooperation among the multiple stakeholders and provide the framework to develop more intelli-gent tools. This paper introduces five complementary European R&D projects in which TECNALIA is col-laborating, very good examples of innovative systems based on these concepts. MOEEBIUS enhances passive and active building elements modelling approaches enabling improved building energy performance simula-tions. HOLISTEEC focuses on building multi-physical simulations considering the neighborhood context. FASUDIR exploits the high potential of GIS tools for urban sustainability analysis and accurate building en-ergy performance evaluation. EFFESUS integrates district and building scales in historic districts. OPTEEMAL develops a platform at district level, based on an IPD approach.This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 680517

Multi-scale urban data models for early-stage suitability assessment of energy conservation measures in historic urban areas

The demand for improving the energy performance of buildings located in the historic districts of cities is as high as the current demand in other city districts. The need to reduce energy consumption and improve the comfort of inhabitants is compounded by the need to preserve an environment of heritage value. The selection of rehabilitation strategies at urban scale offers significant benefits, but makes the process long and costly. Therefore, methods or tools are necessary to establish a rapid assessment that facilitates strategic decision making and a deeper analysis of a reduced number of alternatives.This paper describes a method that supports decision making regarding the suitability of Energy Conservation Measures (ECMs) in historic districts at early stages. The method considers the improvement of the energy performance of buildings as a positive impact, balanced with the negative impacts that the implementation of ECMs could produce. A CityGML-based urban model allows the automation of a multi-scale assessment for different ECMs and provides possible global energy demand reductions. This method, combined with an economic evaluation, can be used by decision makers for large-scale energy retrofitting. The applicability of the method is demonstrated through implementation in the historic city of Santiago de Compostela.The authors gratefully acknowledge the European Commission for providing financial support during the research under the EFFESUS project (Grant Agreement Number 314678)

Gestión colaborativa de modelos de ciudades 3D durante su ciclo de vida basadas en servicios en la nube

En este artículo se presenta una aproximación a la gestión de la información urbana en 3D a lo largo del ciclo de vida de la información, desde la generación hasta su utilización, pasando por la edición y mantenimiento continuo del contenido

Automatised and georeferenced energy assessment of an Antwerp district based on cadastral data

Municipalities play a key role in supporting Europe's energy transition towards a low-carbon economy. However, there is a lack of tools to allow municipalities to easily formulate a detailed energy vision for their city. Nevertheless, most municipalities have access to georeferenced cartographic and cadastre information, including that on basic building characteristics. This article describes an innovative method to calculate and display the current hourly thermal energy demand for each building in a district based on basic cartography, cadastre, and degree-day values. The method is divided into two main blocks: (1) input data processing to obtain geometric information (e.g. geolocation, building and facades’ dimensions) and semantic data (e.g. use, year of construction), and (2) district energy assessment to calculate the thermal energy demand using data obtained in block 1. The proposed method has been applied and tested in the historical district of Antwerp. The reliability and thoroughness of the results obtained using the method are demonstrated based on two different validations: (1) comparison of the results with those calculated using an existing dynamic energy simulation tool, and (2) comparison of the results with the real gas consumption of a partial sector of the selected district. The first validation shows that the average difference between the two methodologies is less than 11% for the heating demand, less than 11% for the cooling demand, and less than 15% for the domestic hot water demand. The second validation shows a 24% difference between the real natural gas consumption and that obtained by new methodology. Finally, the results have been presented to the municipality of Antwerp, which plans to use the method to design the district heating expansion within the city centre. Furthermore, sensitivity assessment was used to determine the relevance of the main input parameters considered in this method, such as the base temperature, energy system schedules, window-to-wall ratio, and solar gains.The work described in this article is partially funded by the PLANHEAT project, Grant Agreement Number 723757, 2016-2019, as part of the call H2020-EE-2016-RIA-IA. The field work for this study was conducted thanks to the active collaboration of the Energy and Environment department of the municipality of Antwerp