•A systematic literature-approach to classify retrofitting is proposed.•An overview of Spain’s previous guidelines on residential retrofits is presented.•A review of financial and subsidies ...mechanisms in Spain to renovate buildings is introduced.•A literature-based matrix on retrofitting actions is presented.•A classification of energy efficiency strategies for retrofitting is proposed.
The building sector is responsible for more than 40% of final energy consumption in Europe; consequently, retrofitting existing buildings can significantly contribute to mitigate greenhouse emissions. Nevertheless, although the European Union has introduced relevant policy instruments, up to now the annual retrofit rates are considerably low with an average of 0.2% at European level. Understanding the past would support the success of the new strategies, such as the recent ones launched through the New Green Deal, which reinforces the importance of renovating existing buildings stock, as the main aim of the renovation wave.
As a starting point for assessing the main challenges to allocate the Recovery funds, this paper provides a review of Spain’s relevant literature to clearly define the characterization of the existing building stock, which actions have been typically considered under the scope of retrofits, and which strategies have been implemented until now, considering both, private and public initiatives and public financial schemes. The present work has a strong focus on energy-related strategies, although other interrelated actions are mentioned, such as accessibility measures and interior refurbishment of dwellings. Differences and similarities within these approaches are presented through the analysis of 27 relevant references of retrofitting actions and 52 references of financial mechanisms.
As in Spain 93% of multifamily buildings were constructed prior to the national transposition of the first Energy Performance Building Directive (EPBD), and therefore are in need of deep energy renovations, the retrofitting of multifamily buildings topic has been widely addressed, even though often in a disjointed manner. The study suggests that although historically there have been several recommended strategies, few are conceived as integral actions, only 15% of the intervention packages refer passive and active energy-related measures and renewable energy incorporation. Furthermore, considering the antiquity of the building stock and the advantage of addressing the topic through clusters, only 63% of the resources directly refer these actions to specific clusters among the six distinctive periods, although in most cases focusing their recommendations on buildings constructed before 1980 where the worst energy performance buildings are concentrated.
Concerning public financial and funding instruments, the research illustrates that there has been a substantial increment of programs over the last years promoting energy-related measures, renewable energy and other complementary aspects such as accessibility and interior renovations, mainly for older clusters. Nevertheless, the funds constitute only 8% of the necessary declared investments, which along with the dispersion between the different procedures and the complexity of the processes, have significantly reduced the global impact of these actions without generating robust and oriented market dynamics.
Despite the several resources found, both financial instruments and guidelines tend to describe in more detail strategies related to heating demand and consumption and not delve into other relevant actions for warmer climates, fact associated both to the dynamics coming from other countries, and to a vision of the past in which people do not consume refrigeration. This clear focus on heating loads rather than cooling could present limitations for warmer regions in the near climate-change future.
The building sector accounts for 40% of the total energy consumption in the EU. It faces great challenges to meet the goal of transforming the existing building stocks into near zero-energy buildings ...by 2050. The development of Energy Performance Certificate (EPC) schemes in the EU provides a powerful and comprehensive information tool to quantitatively predict annual energy demand from the building stock, creating a demand-driven market for energy-effective buildings. Properties with improved energy rating have had a positive impact on property investments and rental return because of the reduced energy bills. In addition, the EPC databases have been applied to energy planning and building renovations. However, it should be mentioned that the current evaluation system faces problems, such as not being fully implemented, delivering low quality and insufficient information to stimulate renovation, therefore requiring improvements to be made. This paper provides a review of the current EPC situations in the EU and discusses the direction of future improvements. The next generation EPC should rely on BIM technology, benefit from big data techniques and use building smart-readiness indicators to create a more reliable, affordable, comprehensive and customer-tailored instrument, which could better represent energy efficiency, together with occupants’ perceived comfort, and air quality. Improved EPC schemes are expected to play an active role in monitoring building performance, future energy planning and quantifying building renovation rates, promoting energy conservation and sustainability.
•Presentation of a brief review of the EPC-related directives.•Review and comparison of the development of the EPC in EU member states.•Discussion on the utilization of the EPC at the urban scale.•Identification of the existing issues and shortcomings in the current EPC.•Proposal of future improvements for the EPC.
Sustainability focused decision-making in building renovation Kamari, Aliakbar; Corrao, Rossella; Kirkegaard, Poul Henning
International journal of sustainable built environment,
December 2017, 2017-12-00, Letnik:
6, Številka:
2
Journal Article
Recenzirano
Odprti dostop
An overview of recent research related to building renovation has revealed that efforts to date do not address sustainability issues comprehensively. The question then arises in regard to the ...holistic sustainability objectives within building renovation context. In order to deal with this question, the research adopts a multi-dimensional approach involving literature review, exploration of existing assessment methods and methodologies, individual and focus group interviews, and application of Soft Systems Methodologies (SSM) with Value Focused Thinking (VFT). In doing so, appropriate data about sustainability objectives have been collected and structured, and subsequently verified using a Delphi study. A sustainability framework was developed in cooperation with University of Palermo and Aarhus University to audit, develop and assess building renovation performance, and support decision-making during the project’s lifecycle. The paper represents the results of research aiming at addressing sustainability of the entire renovation effort including new categories, criteria, and indicators. The developed framework can be applied during different project stages and to assist in the consideration of the sustainability issues through support of decision-making and communication with relevant stakeholders. Early in a project, it can be used to identify key performance criteria, and later to evaluate/compare the pros and cons of alternative retrofitting solutions either during the design stage or upon the project completion. According to the procedure of the consensus-based process for the development of an effective sustainability decision-making framework which was employed in this study, the outcome can also be considered as an outset step intended for the establishment of a Decision Support Systems (DSS) and assessment tool suited to building renovation context.
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•The integrated analysis of LCA and LCCA of building renovation is performed considering future uncertainties.•The robust optimal renovation solution is identified within conventional ...and bio-based materials.•Bio-based materials are considered including dynamic carbon storage analysis.
Boosting building renovation is urgently needed to achieve carbon neutrality by 2050. Building retrofit can be achieved by energy-efficient measures such as thermal insulation or replacement of a fossil heating system. Currently, conventional materials that are mostly used for envelope insulation raising the risk of a lock-in situation where measures to mitigate climate change are actually contributing to it. Bio-based materials are a promising alternative as they can be used to not only reduce the energy consumption of a building but also temporarily store carbon. To evaluate the potential benefits of such materials, life cycle assessment (LCA) and life cycle cost analysis (LCCA) are commonly used. Such assessment allows the analysis of a building over its whole life. However, considering that buildings are very long lasting systems, many associated uncertainties can affect the outcome of LCA and LCCA. To account for all the uncertainty sources and provide a robust solution for building renovation, uncertainty quantification can be applied. In this paper, we use robust optimization under uncertainties to define the most cost-effective and climate-friendly solution. We apply bio-based materials and include carbon storage calculation in the integrated LCA and LCCA. For the robust optimization, we use a novel methodology combining a well-known non-dominated sorting genetic algorithm II (NSGA-II) with surrogate modeling to lower computational cost. The methodology is applied for a case study located in Switzerland. The results show that bio-based materials provide a robust solution for building renovation but to achieve the highest reduction potential, bio-based envelope insulation should be combined with the replacement of the existing fossil heating system.
The article dwells on the results of the search for the archeological site--Ashlama-Saray--the country palace of the Crimean Khans. The palace was built in the second half of the 17th century. At the ...end of the 18th century, the main buildings of the palace were reconstructed. Currently, the ruins of the palace are not identified on the surface. The location of this monument was determined by a general plan of Bakhchisaray city. During the series of archaeological and natural-scientific works carried out in 2015-2016, this palace was precisely localized in the valley of Ashlama-Dere.
Green building has drawn worldwide attention due to the adverse impact of construction on the environment. This research presents a Building Information Modeling (BIM) based evaluation system for the ...performance assessment of green buildings. Combining BIM technology with green building analysis, the proposed approach can fully utilize the advantages of the BIM model and quickly conduct green building evaluation. A green building evaluation framework is constructed, which evaluates the green building performance from five aspects, i.e., the main building, the building envelope, the heating, ventilation and air conditioning (HVAC), the lighting and equipment, and extra points. A case study is performed to test the applicability and effectiveness of the proposed approach. Important findings are: (1) The performance of the target green building is determined as 0.87 (i.e., a fairly poor level), but it could be upgraded to 1.32 (i.e., a good level) with the consideration of extra points for the green building evaluation (2) Building renovation measures (i.e., improving the building envelop, HVAC, and lighting and equipment); could improve the performance of the green building by 31.5% on average. A synergetic impact exists among these renovation measures, where the impact of renovating all three aspects is greater than simply the sum of taking three individual measures; (3) Optimization of the green building performance could not only reduce the energy consumption but also create a more comfortable environment for the occupants, where severe conditions could be greatly reduced. The novelty of this research lies in (a) presenting a BIM-based model that is able to effectively perform the green building evaluation and optimization in a wide range and also incorporate the regional features as needed; (b) proposing a novel grading rule that makes influential factors under different standards measurable in a more intuitive manner.
In this paper, an integrated approach targeting sustainability, safety and resilience is envisioned for the renovation of the post-Second World War RC buildings clustered in urban outskirts. The ...solution stems as an enhancement of the widespread camouflage practice, which targets energy efficiency and architectural restyling by complementing the building with a technological double skin, self-supported on an independent exoskeleton. Based on this integrated approach, the exoskeleton can be further engineered to also enable structural safety and resilience. Life cycle thinking is addressed to re-conceive traditional structural design approaches, guaranteeing safety, while minimising costs and environmental impacts over the building life cycle. Accurate selection of materials and dry technologies enables adaptability, reparability and maintenance, and total recyclability/reuse at end-of-life. The intervention is carried out from outside, avoiding relocation of the inhabitants and possible building downtime. The paper introduces a possible framework for engineers, technologists and architects to design new holistic renovation interventions, for which innovative solution sets are required. Possible structural techniques to be coupled with energy refurbishment are proposed. As a proof of concept, the envisaged holistic renovation strategy is applied to a reference building, and benefits entailed in combining structural safety measures within an integrated intervention are commented.
•Four major future changes at supply and demand side are quantified.•Influences of the changes on the transitions of three DHC systems are analyzed.•Bi-directional 5GDHC is economically feasible with ...demand changes.•Opposite influences from future electricity prices are found with wind power and nuclear.•TES is less suitable for heating and power synergy in 5GDHC.
District energy systems are about to shift towards closer temperature configurations, i.e. low-temperature district heating and high-temperature district cooling. Challenges and benefits of these transitions are mostly analyzed from a perspective of current energy demand and supply scenarios while the influence from future changes in these domains remains unknown. Based on a representative residential community in the Nordic district heating context, centralized district heating and cooling (DHC), ultra-low temperature district heating (ULTDH), and bi-directional fifth generation 5GDHC systems were assessed from technical, economical, and environmental aspects. Moreover, the applications of thermal energy storage (TES) and their roles in the future DHC systems were also investigated. The assessment was done by a generalized methodology framework, integrating the future changes, multiple operation scenarios modellings and system design optimizations. Results suggest that in the future low-energy building stock, the increased cooling demand makes the 5GDHC system the most economically attractive choice. In the supply side, with a 50% share of wind power in the future national grid, the electricity prices can make 5GDHC and ULTDHC either cost-saving or more expensive compared to the central DHC system dependent on if nuclear plants are decommissioned or not. Besides, with increasing power production from VRE, the limited application of TES for active shift of electricity demand is found when a system’s heat-to-power ratio is high. The methodology framework can be applied to similar systems to increase the understandings on system transitions.
Changes in weather conditions due to global warming affect the energy demand of buildings, resulting in changes in the installed heat capacity of district heating systems. The study provides a ...methodology for assessing the potential effects of climate change in combination with renovation of existing building stock on building heat demand. The system dynamics approach was used for investigation of the interlinkages and causality of energy efficiency, global warming, and total installed heat source capacity. Variations in the heating load of a district heating system due to improvements in building energy efficiency were studied in combination with three climate change scenarios. The optimal balance point between investment at the heat source side and at the heat consumers side was also investigated. The interaction of global warming, building heat demand and installed capacity of the district heating system was identified by the levelized investment approach. The study shows that global warming directly influences the heating degree-days and reduces the heat demand in the case study considered (part of the Riga city). A significantly higher impact on heat demand could be achieved by implementation of building renovation, however the funding available for this purpose is insufficient in the studied case.
•The impact of global warming reduces heat demand by 13, 17, and 24% in low, medium, and high scenarios.•Provided methodology couples the system dynamic approach with the building heat balance model.•Investment in heat saving by the renovation of buildings and heat production technology are interlinked.
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