Currently, a life cycle assessment is mostly used in a static way to assess the environmental impacts of the energy renovation of buildings. However, various aspects of energy renovation vary in time. This paper reports the development of a framework for a dynamic life cycle assessment and its application to assess the energy renovation of buildings. To investigate whether a dynamic approach leads to different decisions than a static approach, several renovation options of a residential house were compared. To identify the main drivers of the impact and to support decision-making for renovation, a shift of the reference study period—as defined in EN 15643-1 and EN 15978—is proposed (from construction to renovation). Interventions related to the energy renovation are modelled as current events, while interventions and processes that happen afterwards are modelled as future events, including dynamic parameters, considering changes in the operational energy use, changes in the energy mix, and future (cleaner) production processes. For a specific case study building, the dynamic approach resulted in a lower environmental impact than the static approach. However, the dynamic approach did not result in other renovation recommendations, except when a dynamic parameter for electricity production was included.
Social housing companies in Flanders are facing the need for a thorough renovation of their building stock in the coming years. This renovation should be in line with the policy targets to reduce the energy use of buildings by 2050. As such thorough renovation scenarios require a high investment cost; a stepwise approach is often implemented. It is important to ensure that the overall investment cost for such a step by step approach is not (much) higher than an “in-depth at-once renovation”. This paper reports on the development of a method to support social housing companies in making a cost-optimal renovation planning for their building stock. Whereas current research focuses on net present value and payback time, this paper considers the life cycle cost for the evaluation of the investments, taking into account: (1) available financial resources over time, (2) various credit facilities over time and (3) various technical options leading to different energy savings. To check consistency and applicability, the method is tested on four case studies. Despite some uncertainties in this early development stage of the method, it is possible to draw some first conclusions based on the assessment of one case study. Since the results of the LCC assessment depend on the assumed economic parameters and expected service life of the building, those parameters have to be estimated with caution. Instead of implementing similar renovation strategies to all buildings, it would be advisable to do a Life Cycle Cost assessment per renovation project to get insight in the efficiency of the renovation strategy in order to use the limited budget of social housing companies more effectively.
The current focus on climate change mitigation is reflected in policy goals to reduce the energy use of buildings. However, buildings are not only responsible for a large share of energy use and corresponding GHG emissions, they moreover require a lot of resources, produce a lot of waste, and emit harmful substances. In this paper, an approach is developed to investigate the most preferred renovation strategies for social housing, considering various parameters such as efficiency of the current and future heating system, service life of the heating system and insulation level of the building envelope. Moreover the reduction in life cycle environmental impact due to the replacement of heating systems by systems with increased efficiency is studied. The results show that for non-insulated buildings an increase of the thermal resistance of the building envelope is more effective than replacing the heating system while for, even poorly, insulated buildings the efficiency of the heating system is more important. A holistic Life Cycle Assessment approach is preferred to assess renovation scenarios as focussing on energy reduction might lead to an increase of the life cycle environmental impact of the building. Although this paper focuses on social housing, the approach is broadly applicable.
As the budget of social housing companies is limited, reducing the energy use of their housing stock to be compliant with current standards and actions plans is an important challenge. Currently social housing companies in Flanders often prefer replacing the heating system to insulating the building envelope due to the lower investment cost and easy implementation. However, the investment in better heating systems has to be repeated several times during the service life of the building. This paper provides insights in the investment cost and life cycle cost of both renovation strategies. Moreover an environmental life cycle assessment provides insights in the environmental impact of the renovation strategies. The analysis reveals that it is recommended to replace heating boilers not earlier than at the end of their technical service life, both from an environmental and economic perspective. Sensitivity analyses show that changes in the estimated remaining building service life and increasing discount rate lead to changes in the life cycle costs but have no influence on the ranking of the renovation scenarios. Changes in the energy price, insulation level and original building type lead to changes in the costs and ranking of the renovation scenarios.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.