Browsing by Author "Oregi, Xabat"
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Item Analysis of life-cycle boundaries for environmental and economic assessment of building energy refurbishment projects(2017-02-01) Oregi, Xabat; Hernandez, Patxi; Hernandez, Rufino; Tecnalia Research & Innovation; PLANIFICACIÓN ENERGÉTICADespite the standardization of the life-cycle assessment methodology for the construction sector, analysts tend to apply some simplifications in relation to the system boundaries, omitting some of the life-cycle stages. In particular, for building energy refurbishment projects, there is a general focus on the operational stage, linked to the main objective of reducing operational energy use. This paper evaluates the relevance of each life-cycle stage in relation to the overall environmental and economic impact on residential building energy refurbishment projects. The results from the analysis of the refurbishment strategies at a case study in Spain show the relatively minor importance of the transport and end of life stages. The construction process stage is also of relatively minor importance regarding the environmental performance. The product, maintenance and replacement stages are generally of higher importance, particularly for economic evaluation. An extensive sensitivity analysis demonstrates the difficulties of simplifying the life-cycle boundaries, suggesting that potential simplifications should take into account various parameters, including the climate region, building typologies, and expected service life. As an example, the results have shown that for cold climate zones and buildings, where large energy savings from energy refurbishment strategies can be achieved, the other life-cycle phases are less important and, in most cases, represent less than 10% of life-cycle environmental impacts.Item Automatised and georeferenced energy assessment of an Antwerp district based on cadastral data(2018-08-15) Oregi, Xabat; Hermoso, Nekane; Prieto, Iñaki; Izkara, Jose Luis; Mabe, Lara; Sismanidis, Panagiotis; Tecnalia Research & Innovation; PLANIFICACIÓN ENERGÉTICA; LABORATORIO DE TRANSFORMACIÓN URBANAMunicipalities 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.Item A catalogue of energy conservation measures (ECM) and a tool for their application in energy simulation models(2020-05) Costa, Gonçal; Sicilia, Álvaro; Oregi, Xabat; Pedrero, Juan; Mabe, Lara; PLANIFICACIÓN ENERGÉTICAOne of the primary objectives in the refurbishment of buildings is to identify the best combination of Energy Conservation Measures (ECMs) in terms of energy efficiency. The current Building Energy Performance (BEP) simulation tools require a great deal of time and effort because data from multiple sources must be properly combined (e.g., building/urban models, ECM catalogues, weather condition files) in order to create energy simulation models. In addition, the process of manually setting up each scenario in order to obtain the most optimal solution is also a demanding and time-consuming task. The growing presence of the Building Information Model/Modelling (BIM) technologies in the Architecture, Engineering and Construction (AEC) industry, combined with the new capabilities to link and integrate data using Semantic Web technologies, is presented as an alternative to automate the simulation process. In this article, we present a system that takes advantage of the capabilities of these technologies to integrate ECM data into BEP simulation models in an automated way. The system is composed of a catalogue of ECM measures described in Resource Description Framework (RDF) and a software component that facilitates their application in the models. The system has been developed in the context of OptEEmAL, a research project aimed at creating a web platform to facilitate building simulations at a district scale. The applicability of the system is demonstrated in a case study of a district-scale project.Item Environmental and Economic Prioritization of Building Energy Refurbishment Strategies with Life-Cycle Approach(2020-05-11) Oregi, Xabat; Hernández, Rufino Javier; Hernandez, Patxi; PLANIFICACIÓN ENERGÉTICAAn increasing number of studies apply life-cycle assessment methodology to assess the impact of a new building or to prioritize between different building refurbishment strategies. Among the different hypotheses to consider during the application of this methodology, the selection of the impact indicator is critical, as this choice will completely change the interpretation of the results. This article proposes applying four indicators that allow analysing the results of a refurbishment project of a residential building with the life-cycle approach: non-renewable primary energy use reduction (NRPER), net energy ratio (NER), internal rate of return (IRR), and life-cycle payback (LC-PB). The combination of environmental and economic indicators when evaluating the results has allowed to prioritize among the different strategies defined for this case study. Furthermore, an extensive sensitivity assessment reflects the high uncertainty of some of the parameters and their high influence on the final results. To this end, new hypotheses related to the following parameters have been considered: reference service life of the building, estimated service life of material, operational energy use, conversion factor, energy price, and inflation rate. The results show that the NRPE use reduction value could vary up to −44%. The variation of the other indicators is also very relevant, reaching variation rates such as 100% in the NER, 450% in the IRR, and 300% in the LC-PB. Finally, the results allow to define the type of input or hypothesis that influences each indicator the most, which is relevant when calibrating the prioritization process for the refurbishment strategy.Item Environmental assessment of four Basque University campuses using the NEST tool(2018-10) Leon, Iñigo; Oregi, Xabat; Marieta, Cristina; Tecnalia Research & InnovationOver the past few years, town planners and architects have been facing increasing demands regarding the performance of urban development projects in terms of environment, quality of life and socio-economic issues. For this reason, several tools capable of assessing their environmental impacts have been developed. NEST (Neighbourhood Evaluation for Sustainable Territories) is a particularly interesting one since it permits performing simultaneous environmental, economic and social analyses at a district scale, in addition to evaluating refurbishment scenarios, with a life cycle perspective. Nowadays, universities can be considered as “small cities” due to their large size, population, and the many complex activities that take place on the campuses; thus, they have a direct and indirect impact on the environment. In this article, the authors present the results obtained from the environmental evaluation of the four campuses of the University of the Basque Country (UPV-EHU), using NEST. First, the evaluation consisted of analysing baseline environmental impacts of the four campuses, and then, in order to reduce environmental impacts, the authors presented numerous refurbishment scenarios for the campuses, according to national and international declarations concerning sustainable development in higher education.Item Evaluation of different refurbishment or improvement strategies to reduce the environmental impact of University campuses(International Building Performance Simulation Association, 2022) Arias, Alba; León, Iñigo; Oregi, Xabat; Marieta, Cristina; Mabe, Lara; Saelens, Dirk; Laverge, Jelle; Boydens, Wim; Helsen, Lieve; PLANIFICACIÓN ENERGÉTICAOver the past few years, urban planners and architects have searched for solutions to improve the performance of urban projects in terms of environmental impact, life quality and socio-economic problems. NEST is an agile and fast tool developed to assess this environmental impact (baseline scenarios and improvements hypotheses) at the district level by a life cycle analysis. The authors of this publication have used NEST in different research projects and have studied different baseline scenarios and evaluated improvement cases. The article presents a summary of the evolution of the research carried out, explaining each case study and the general conclusions obtained. It also presents the current research project focused on the utilisation of renewable energy sources in the campuses in order to reduce their environmental impact.Item From rooftops to roads: Bilbao's geospatial solar and EV fusion(2024-05) Javanmardi, Komar; Hernández, Patxi; Oregi, Xabat; PLANIFICACIÓN ENERGÉTICAThe electrification of mobility is a promising solution to effectively reduce CO2 emissions in urban areas. The integration of electric vehicles (EVs) and solar energy is a practical approach for mitigating the strain on power grids and storing surplus energy. However, the selection of sites for EV charging stations (EVCS) integrated with renewable sources is challenging. This study aims to develop a scalable and highly spatially explicit methodology for identifying optimal locations for EVCS powered by photovoltaic (PV). A novel decision framework for EVCS site selection is put forward, entailing the design of a parametric solar tool, and integrating PV and EV systems to power EVCS. This GIS-based methodology can be used to evaluate the parameters and constraints for EVCS placement, estimate solar rooftop potential, and integrate them into the power grid. The local solar energy potential complements the installation of additional on-street charging points in power substations. Results show that the city centre and a small region in the east are the most suitable locations for installing EVCS in Bilbao. Moreover, the results demonstrate the potential for charging 16% more EVs through a grid-connected PV system without increasing the capacity of the distribution substations of a district in Bilbao.Item Integrating simplified and full life cycle approaches in decision making for building energy refurbishment: Benefits and Barriers(2015) Oregi, Xabat; Hernandez, Patxi; Gazulla, Cristina; Isasa, Marina; Tecnalia Research & Innovation; PLANIFICACIÓN ENERGÉTICAThe life cycle assessment (LCA) method is a powerful tool that can serve to aid decision making regarding the environmental benefits of refurbishment projects. However, due to the relative complexity of LCA studies, simplified LCA methodologies are frequently used, focusing on just some of the building life cycle phases or a reduced number of indicators. The most common and widespread simplification is to only evaluate the differences a refurbishment project makes on the operational energy use of the building. This paper compares the results of applying full LCA, simplified LCA and operational energy use assessment in a refurbishment case study. Results show that simplified LCA methodologies including building use phase and product manufacturing phase can generally be sufficiently accurate to aid decision making for building energy refurbishment, as other building life cycle phases related to transport of products, on site construction, deconstruction or end of life represent a generally negligible part of the total life cycle impacts, both in terms of resource use or environmental impacts. Barriers and benefits of applying simplified LCA approaches to building energy refurbishment projects are subsequently discussed.Item Life-cycle assessment of buildings(Elsevier, 2018-01-01) Hernandez, Patxi; Oregi, Xabat; Longo, Sonia; Cellura, Maurizio; PLANIFICACIÓN ENERGÉTICA; Tecnalia Research & InnovationAs building energy efficiency improves and energy use in operation of buildings is reduced, it is increasingly important to take into account other phases of the building life cycle. A consistent methodology needs to be applied for evaluating impacts of products used through the building whole life cycle, including their manufacturing, transport, installation, use, maintenance and substitution, and end of life. This life-cycle perspective serves to evaluate if the environmental benefits of reducing building energy use are not outweighed by environmental impacts from other building life-cycle phases. The methodology can also integrate cost and even social indicators to provide a wider life-cycle sustainability performance evaluation.Item A Multi-objective Harmony Search Algorithm for Optimal Energy and Environmental Refurbishment at District Level Scale(Springer Singapore, 2017) Manjarres, Diana; Mabe, Lara; Oregi, Xabat; Landa-Torres, Itziar; Arrizabalaga, Eneko; Del Ser, Javier; Tecnalia Research & Innovation; IA; PLANIFICACIÓN ENERGÉTICANowadays municipalities are facing an increasing commitment regarding the energy and environmental performance of cities and districts. The multiple factors that characterize a district scenario, such as: refurbishment strategies’ selection, combination of passive, active and control measures, the surface to be refurbished and the generation systems to be substituted will highly influence the final impacts of the refurbishment solution. In order to answer this increasing demand and consider all above-mentioned district factors, municipalities need optimisation methods supporting the decision making process at district level scale when defining cost-effective refurbishment scenarios. Furthermore, the optimisation process should enable the evaluation of feasible solutions at district scale taking into account that each district and building has specific boundaries and barriers. Considering these needs, this paper presents a multi-objective approach allowing a simultaneous environmental and economic assessment of refurbishment scenarios at district scale. With the aim at demonstrating the effectiveness of the proposed approach, a real scenario of Gros district in the city of Donostia-San Sebastian (North of Spain) is presented. After analysing the baseline scenario in terms of energy performance, environmental and economic impacts, the multi-objective Harmony Search algorithm has been employed to assess the goal of reducing the environmental impacts in terms of Global Warming Potential (GWP) and minimizing the investment cost obtaining the best ranking of economic and environmental refurbishment scenarios for the Gros district.Item Plug and Play Modular Façade Construction System for Renovation for Residential Buildings(2021-09-18) Torres, Jorge; Garay-Martinez, Roberto; Oregi, Xabat; Torrens-Galdiz, J. Ignacio; Uriarte-Arrien, Amaia; Pracucci, Alessandro; Casadei, Oscar; Magnani, Sara; Arroyo, Noemi; Cea, Angel M.; Tecnalia Research & Innovation; E&I SEGURAS Y RESILIENTES; EDIFICACIÓN DE ENERGÍA POSITIVAThe present paper focuses on the architectural and constructional features required to ensure that building envelope renovation are safe, functional, and adaptable to the building stock, with particular focus on “plug and play” modular facade construction systems. It presents the design of one such system and how it addresses these issues. The outcome of early-stage functional test with a full-scale mock-up system, as well as its applicability to a real construction project is presented. It is found crucial to obtain high quality information about the status of the existing façade with the use of modern technologies such as topographic surveys or 3D scans and point cloud. Detailed design processes are required to ensure the compatibility of manufacture and installation tolerances, along with anchor systems that deliver flexibility for adjustment, and construction processes adapting standard installation methods to the architectural particularities of each case that may hinder its use or require some modification in each situation. This prefabricated plug and play modular system has been tested by reproducing the holistic methodology and new technologies in the market by means of real demonstrators. When compared to more conventional construction methods, this system achieves savings in a real case of 50% (time), 30% (materials) and 25% (waste), thus achieving significant economic savings.Item Sensitivity assessment of a district energy assessment characterisation model based on cadastral data(2018-08) Oregi, Xabat; Hermoso, Nekane; Arrizabalaga, Eneko; Mabe, Lara; Munoz, Inigo; Tecnalia Research & Innovation; PLANIFICACIÓN ENERGÉTICASustainable energy planning of cities is a complex problem which should address the comparative analysis of alternative future energy scenarios form a social, economic and environmental point of view. In this regard, the development of methods and tools to allow building energy demand characterization of large areas is becoming one of the main challenges in this field. New studies focused on the energy diagnosis of districts and cities with different location and climatic conditions are necessary to calibrate current methods and assumptions, as well as for the replication of the validated method in other cities around the globe. This paper provides a comparative analysis of the results obtained during the sensitivity assessment of a specific tool for the building energy demand characterization at city scale developed by Tecnalia in the European research project PlanHeat for four different European cities. During this calibration process, the influence of the main parameters that can be adjusted within the tool is evaluated and discussed. Results show that the relevance of adjusting properly each parameter varies depending on the climate zone of the city evaluated and other characteristics of the conjunction of buildings included in each district.Item SOFIAS – Software for life-cycle assessment and environmental rating of buildings(2016-06-29) Oregi, Xabat; Tenorio, Jose Antonio; Gazulla, Cristina; Zabalza, Ignacio; Cambra, David; Leao, Susana; Mabe, Lara; Otero, Sheila; Raigosa, Juliana; Oregi Isasi, X.; Tecnalia Research & Innovation; PLANIFICACIÓN ENERGÉTICAThis paper describes the development process of a new software tool, called SOFIAS (Software for a Sustainable Architecture), funded by the Spanish Ministry of Economy and Competitivenes. Following CEN/TC 350 standard on environmental assessment of buildings, the tool aims at assisting building professionals on reducing the life-cycle environmental impact through the design of new buildings and the refurbishment of existing ones. In addition, SOFIAS provides a rating system based on the Life Cycle Assessment (LCA) methodology. This paper explains the innovative aspects of this software, the working methodology and the different type of results that can be obtained using SOFIAS.Item Sustainability assessment of three districts in the city of Donostia through the NEST simulation tool(2016-11-01) Oregi, Xabat; Pousse, Maxime; Mabe, Lara; Escudero, Alexandre; Mardaras, Iker; Tecnalia Research & Innovation; PLANIFICACIÓN ENERGÉTICANowadays, urbanists are facing increasing demands regarding the performance of urban development projects in terms of environment, quality of life and socio-economic issues. In order to address these increasing demands, actors involved in urban development projects need tools capable of assessing their impacts. These tools should also enable the comparison of all potential scenarios. Taking into account these needs, Nobatek and Tecnalia have developed NEST (Neighbourhood Evaluation for Sustainable Territories), which is one of the first tools that allows for a simultaneous environmental, economic and social analysis at the district scale, with a life-cycle perspective. Using NEST, the authors of this work carried out an environmental and social evaluation of three districts in the city of Donostia, in the framework of the Essai Urbain research project. The evaluation first consisted of analysing baseline environmental impacts of the three districts. Then, with the objective of reducing environmental impacts and increasing social well-being, the authors proposed several refurbishment scenarios for the studied districts, focusing on energy issues. The study was performed in close collaboration with the city of Donostia, which enabled the identification and selection of the most relevant scenarios from an environmental standpoint. Moreover, the NEST software has caught the attention of the project's stakeholders regarding environmental issues. Finally, NEST seems to be an interesting alternative in accounting for sustainable development issues from the early stages of urban development projects.Item Techno-economic evaluation of building energy refurbishment processes from a life cycle perspective(UPV-EHU, 2015-12-18) Oregi, Xabat; Hernández, Rufino J.; Hernandez, PatxiBased on the new energy performance limitations determinate by the Directive 2010/31/EU, the buildings become more energy efficient and the impact of the operational stages is reduced, increasing the relevance of the environmental and economic impact of the other life cycle stages. In addition, the energy refurbishment requirements are increasing, generating the need to integrate the life cycle methodology during the prioritization process between the different energy-efficient retrofitting strategies for buildings. However, despite the Life Cycle methodology has already been standardized, as buildings are extremely complex systems, a lot of studies usually apply some simplifications to reduce the time of the evaluation. Based on these simplifications and seeing that when talking about the energy renovation of an existing building, the main objective is focused on reducing its impact during its operational stage, are being generating various questions in relation to the need and added value of the application of the Life Cycle methodology: what extent can the boundary system be simplified without reducing the accuracy of the results? What is the relationship between the impact reduced during the operational stage and the impact generated during the other stages of the life cycle? What are the most relevant parameters and/or stages when conducting a study and making a decision? In order to seek an answer to these questions on the basis of the EN 15978 and prEN 16627 standards, this research work proposed a quantitative methodology to allow assessment of the impact generated at each stage in the life cycle of an energy-efficient retrofitting of a building. The methodology proposed is validated using a building constructed in San Sebastian (Spain) in 1963. However, given the possible disadvantages of treating these results based on a single case of study as overall conclusions, the research proposes an exhaustive sensitivity analysis presenting new scenarios related to most of the parameters that have a direct influence on the method of calculation. After analysing all the new scenarios defined using these data, the results obtained make it possible to give an answer concerning the relationship between the increased accuracy of the results and the quantification of all the stages in the life cycle.Item Two-Stage Multi-Objective Meta-Heuristics for Environmental and Cost-Optimal Energy Refurbishment at District Level(2019) Manjarres, Diana; Mabe, Lara; Oregi, Xabat; Landa-Torres, Itziar; Tecnalia Research & Innovation; IA; PLANIFICACIÓN ENERGÉTICAEnergy efficiency and environmental performance optimization at the district level are following an upward trend mostly triggered by minimizing the Global Warming Potential (GWP) to 20% by 2020 and 40% by 2030 settled by the European Union (EU) compared with 1990 levels. This paper advances over the state of the art by proposing two novel multi-objective algorithms, named Non-dominated Sorting Genetic Algorithm (NSGA-II) and Multi-Objective Harmony Search (MOHS), aimed at achieving cost-effective energy refurbishment scenarios and allowing at district level the decision-making procedure. This challenge is not trivial since the optimisation process must provide feasible solutions for a simultaneous environmental and economic assessment at district scale taking into consideration highly demanding real-based constraints regarding district and buildings’ specific requirements. Consequently, in this paper, a two-stage optimization methodology is proposed in order to reduce the energy demand and fossil fuel consumption with an affordable investment cost at building level and minimize the total payback time while minimizing the GWP at district level. Aimed at demonstrating the effectiveness of the proposed two-stage multi-objective approaches, this work presents simulation results at two real district case studies in Donostia-San Sebastian (Spain) for which up to a 30% of reduction of GWP at district level is obtained for a Payback Time (PT) of 2–3 years.Item Use of ICT tools for integration of energy in urban planning projects(2015-12-01) Oregi, Xabat; Roth, Esther; Alsema, Erik; van Ginkel, Maarten; Struik, David; Tecnalia Research & InnovationWithin the European collaboration project SUSREG a number of software tools for sustainable urban planning were applied and tested in the context of real case studies. Three types of ICT tools can be distinguished: Neighbourhood Sustainability Assessment Tools, Rating systems and LCA-LCC Tools. We discuss in more detail the Autodesk Ecotect Analysis tool, as applied in the case study of an old railway area in Burgos, Spain. The second tool is GPR Urban Planning, which was applied to a city expansion plan for the City of Nijmegen, The Netherlands. We conclude that ICT tools are often applied rather late in the planning process which neglects their potential advantages with respect to integral assessment and stakeholder communication