The impact of renovation measures on building environmental performance: An emergy approach (original) (raw)

Energy savings and carbon reduction due to renovated buildings

International Review of Mechanical Engineering

The paper deals with an energy saving case study of a renovated building in comparison with the building energy balance before renovation. The renovation was carried out in the building envelopes such as external walls, floor on ground and the flat roof for the improvement of thermal insulation properties of the investigated building. The renovation has brought forward energy saving effects, which are important for both reducing energy consumption for heating during winter seasons and the associated heating costs. In addition, the renovation represents a positive environmental impact due to the reduction of carbon dioxide emissions from such dwellings. The energy renovation of the case study building evaluated was used as a base for an estimation of energy savings and reductions of carbon emissions within a housing estate residential complex with twenty similar buildings. The study presents the importance of having such thermally insulated building envelopes in building together with windows that also have good thermal property and insulation quality for the reduction of overall energy consumption.

Co-benefits of energy related building renovation: demonstration of their impact on the assessment of energy related building renovation (Annex 56)

2017

This publication has been compiled with reasonable skill and care. However, neither University of Minho nor the EBC Contracting Parties (of the International Energy Agency Implementing Agreement for a Programme of Research and Development on Energy in Buildings and Communities) make any representation as to the adequacy or accuracy of the information contained herein, or as to its suitability for any particular application, and accept no responsibility or liability arising out of the use of this publication. The information contained herein does not supersede the requirements given in any national codes, regulations or standards, and should not be regarded as a substitute for the need to obtain specific professional advice for any particular application.

Benefits from Energy Related Building Renovation Beyond Costs, Energy and Emissions

Energy Procedia, 2015

The relevance of the building sector in the global energy use as well as in the global carbon emissions, both in the developed and developing countries, makes the improvement of the overall energy performance of existing buildings an important part of the actions to mitigate climate changes. Regardless of this potential for energy and emissions saving, large scale building renovation has been found hard to trigger, mainly because present standards are mainly focused on new buildings, not responding effectively to the numerous technical, functional and economic constraints of the existing ones. One of the common problems in the assessment of building renovation scenarios is that only energy savings and costs are normally considered, despite the fact that it has been long recognized that investment on energy efficiency and low carbon technologies yield several benefits beyond the value of saved energy which can be as important as the energy cost savings process. Based on the analysis of significant literature and several case studies, the relevance of co-benefits achieved in the renovation process is highlighted. These benefits can be felt at the building level by the owner or user (like increased user comfort, fewer problems with building physics, improved aesthetics) and should therefore be considered in the definition of the renovation measures, but also at the level of the society as a whole (like health effects, job creation, energy security, impact on climate change), and from this perspective, policy makers must be aware of the possible crossed impacts among different areas of the society for the development of public policies.

On calculated and actual energy savings from thermal building renovations – Long term field evaluation of multifamily buildings

Energy and Buildings, 2020

Thermal renovation of existing buildings is one of the most popular actions to decrease the energy consumption for heating and cooling. However, to the best of the authors' knowledge, there are no long-term field studies that present the influence of hydraulic rebalancing of the heating system after the thermal renovation of the building's envelope on the level of achieving the calculated energy savings. This work presents the results from a field study that collected data on actual operational energy over several heating seasons, from 11 similar multifamily buildings in Poland. All buildings were thermally renovated by insulating their envelope, while for some of them the works were completed by a hydraulic rebalance of their heating system. The modernization activities were implemented with a different sequence. For another group of buildings, the hydraulic balancing of the heating system was not performed after the envelope thermal renovation. This offered an excellent opportunity to compare the actual energy performance of the renovated buildings and quantify the achieved energy savings resulting from different practices. Energy audits were performed in all buildings in order to calculate the energy use of the buildings before and after the renovations. These estimates were then compared with the actual energy savings from the monitored energy use for all renovated buildings. Accordingly, the actual energy savings range between 8.8% and 74.8% of calculated energy savings, depending on the different renovations. The actual payback time for the analysed modernization actions was longer than the calculated one, ranging between 3.1 and 104.8 heating seasons.

Feasibility of energy saving renovation measures in urban buildings

Energy and Buildings, 2002

The energy renovation of existing buildings is an important tool for the reduction of energy consumption in the building sector, the improvement of prevailing indoor thermal comfort conditions and also for the improvement of environmental conditions in urban areas. At the same time, it is a technical, economic and social problem, due to the way in which many cities have been built and the restrictions imposed by economic constrains that tantalise most countries in South-Eastern Europe, and also Greece. It applies particularly in Northern Greece, with its cold and prolonged heating season, where a series of studies was carried out since 1994 to approach the problem and develop viable proposals. Public and mixed-use buildings form a signi®cant part of the building stock and are therefore a primary candidate for energy saving measures, especially as they also play the role of a`pilot-demonstrator' for the private owned buildings. However, due to the low energy prices that prevailed over the last 10 years, and as energy saving measurements are capital intensive investments, little was done in that direction. The recent sharp increase in oil prices proved that this was a short-sighted policy. In the following paper are presented the results of a study that aimed to determine the potential of energy saving renovation measures, in a representative sample of buildings under realistic conditions, to evaluate the feasibility of these measures, and also the way in which this feasibility is being analysed, under the rapidly changing economic conditions. #

Energy saving renovation: Analysis of critical factors at the building level

2008

To accelerate energy saving in the built environment, housing associations should apply low-energy techniques in existing houses which are in need of renovation. Because of a lack of knowledge it is difficult for housing associations to determine which low-energy technique has the best results for energy consumption and CO 2 -emissions. In this research a decision support tool will be developed with a new energy performance calculation method at district level including aspects like houses, transport and households. In this paper we focus on the critical factors at the building level that should be included in a district data model. Therefore we have executed a screening analysis to indicate what these critical factors are.

Life Cycle Assessment of Building Renovation Measures–Trade-off between Building Materials and Energy

Energies

The scope of this study is to assess how different energy efficient renovation strategies affect the environmental impacts of a multi-family house in a Nordic climate within district heating systems. The European Union has set ambitious targets to reduce energy use and greenhouse gas emissions by the year 2030. There is special attention on reducing the life cycle emissions in the buildings sector. However, the focus has often been on new buildings, although existing buildings represent great potential within the building stock in Europe. In this study, four different renovation scenarios were analyzed with the commercially available life cycle assessment software that follows the European Committee for Standardization (CEN) standard. This study covers all life cycle steps from the cradle to the grave for a residential building in Borlänge, Sweden, where renewable energy dominates. The four scenarios included reduced indoor temperature, improved thermal properties of building materi...

PRELUDE Roadmap for Building Renovation: set of rules for renovation actions to optimize building energy performance

2022

In the context of climate change and the environmental and energy constraints we face, it is essential to develop methods to encourage the implementation of efficient solutions for building renovation. One of the objectives of the European PRELUDE project [1] is to develop a "Building Renovation Roadmap"(BRR) aimed at facilitating decision-making to foster the most efficient refurbishment actions, the implementation of innovative solutions and the promotion of renewable energy sources in the renovation process of existing buildings. In this context, Estia is working on the development of inference rules that will make it possible. On the basis of a diagnosis such as the Energy Performance Certificate, it will help establishing a list of priority actions. The dynamics that drive this project permit to decrease the subjectivity of a human decisions making scheme. While simulation generates digital technical data, interpretation requires the translation of this data into natural language. The purpose is to automate the translation of the results to provide advice and facilitate decision-making. In medicine, the diagnostic phase is a process by which a disease is identified by its symptoms. Similarly, the idea of the process is to target the faulty elements potentially responsible for poor performance and to propose remedial solutions. The system is based on the development of fuzzy logic rules [2],[3]. This choice was made to be able to manipulate notions of membership with truth levels between 0 and 1, and to deliver messages in a linguistic form, understandable by non-specialist users. For example, if performance is low and parameter x is unfavourable, the algorithm can gives an incentive to improve the parameter such as: "you COULD, SHOULD or MUST change parameter x". Regarding energy performance analysis, the following domains are addressed: heating, domestic hot water, cooling, lighting. Regarding the parameters, the analysis covers the following topics: Characteristics of the building envelope. and of the technical installations (heat production-distribution, ventilation system, electric lighting, etc.). This paper describes the methodology used, lists the fields studied and outlines the expected outcomes of the project.

Promotion of Sustainable Renovation in the Built Environment

2012

According to the Swedish Government's set targets for energy use and environmental quality imposed by the European Union, the total energy per heated unit area in residential and commercial buildings will have to be decreased by 20% in 2020 and 50% by 2050 in relation to the annual consumption of 1995. The building sector should additionally be completely independent of fossil fuels for energy usage, with the increasing sector of renewable energy continuously growing until 2020. In its current state, the number of multistory buildings and single-family houses in Sweden exceeds 4 000 000 units. In order to attain the set goals, renovation of the existing housing stock is a necessity given its current relatively slow turnover. As a result of the Swedish Million Unit Program undertaken during 1965 − 1974, about 750 000 apartments are currently in need of renovation in order to meet today's building standards. Simultaneously, new buildings are built with energy efficiency in mind. In this study an early stage methodology is developed for building refurbishment that takes advantage of a multi-faceted approach. The methodology comprises of multiple dimensions related to a techno-economic, environmental and building occupancy approach. The work presented herein includes a thorough literature review of decision making tools within the built environment and identifies major research efforts in sustainable refurbishment. The technical aspect of this study deals with the proper identification of high-efficient insulation materials that would serve one of the set purposes of energy efficiency when utilized within building envelopes. Further, results are shown for case studies, in which economic investments in Vacuum Insulation Panels (VIPs) and a coupled heat and moisture transport for predefined configurations of VIPs with supplementary insulation of balcony slabs and wall cross-sections are considered. The developed methodology also examines simulations of the total energy consumption utilizing a set of different insulation materials such as mineral wool and VIPs, for a number of locations in Northern and Southern Europe. The research findings of this study identify several aspects of a new developed tool for decision making, to be used in sustainable renovation and refurbishment. vii

Exergy efficiency analysis of a refurbished dwelling: a case study in Ljubljana, Slovenia

Buildings contribute almost half of the world’s carbon dioxide (CO2) emissions. Energy and water consumption are some of the largest and fastest growing pressures on the global environment. The use of energy is mainly attributed to the heating and cooling of buildings. The type of materials used in the construction of buildings plays a significant role in the life-cycle emissions of each dwelling. Changing the material use in the construction of an existing building and adding insulation could have a major impact on energy use and the environment of the building in its entire life cycle. This paper investigates the amount of exergy savings and the decrease in CO2 emissions resulting from the refurbishing of an existing building in Ljubljana. This study results from the growing awareness that in the choice of building materials, the designer must consider not only the requirements of the owner and occupier of the building, but also the resulting energy savings, the resource base and the effects of the manufacturing and processing of building materials on the environment. The exergy efficiency of the material use is calculated and the environmental impact assessment of energy and material use is accounted for.