Building service life and its effect on the life cycle embodied energy of buildings

doi:10.1016/j.energy.2014.10.093

Energy

Volume 79, 1 January 2015, Pages 140-148

https://doi.org/10.1016/j.energy.2014.10.093 Get rights and content

Highlights

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We analyse the relationship between a building's service life and embodied energy.
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We model the life cycle embodied energy of a residential building.
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We use a comprehensive hybrid embodied energy assessment technique.
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A building's service life has a significant effect on its embodied energy.
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Increasing building service life can reduce embodied energy by up to 29%.

Abstract

The building sector is responsible for significant energy demands. An understanding of where this occurs across the building life cycle is critical for optimal targeting of energy reduction efforts. The energy embodied in a building can be significant, yet is not well understood, especially the on-going ‘recurrent’ embodied energy associated with material replacement and building refurbishment. A key factor affecting this ‘recurrent’ embodied energy is a building's service life. The aim of this study was to investigate the relationship between the service life and the life cycle embodied energy of buildings. The embodied energy of a detached residential building was calculated for a building service life range of 1–150 years. The results show that variations in building service life can have a considerable effect on the life cycle embodied energy demand of a building. A 29% reduction in life cycle embodied energy was found for the case study building by extending its life from 50 to 150 years. This indicates the importance of including recurrent embodied energy in building life cycle energy analyses as well as integrating building service life considerations when designing and managing buildings for improved energy performance.

Introduction

In recent decades, buildings have become a critical factor in efforts to reduce global greenhouse gas emissions. The building sector is responsible for significant energy demand globally which results in greenhouse gas emissions along with the depletion of energy resources. Buildings account for 30–40% of energy use and greenhouse gas emissions in many countries around the world with a significant share of this attributable to residential buildings [1], [2]. This situation is further exacerbated with the use of fossil fuels as the main source for energy production around the globe. All fossil fuels emit carbon dioxide to the atmosphere when burned. The carbon dioxide helps trap heat in the atmosphere, a main contributor to the potential warming of the Earth [3]. The previous decade was one of the warmest in recorded history and carbon dioxide concentrations have now reached over 401 ppm (parts per million) [4], well above what is considered to be the upper safety limit for atmospheric CO₂, of 350 ppm. In the last century, world population has grown rapidly along with an increase in life expectancy and per capita energy use [5]. It is expected that this trend will continue. It is therefore of critical importance that energy demand within the built environment is addressed to avoid further degradation of the natural environment.

These impacts are not limited to the energy use associated with building operation, but also include energy use associated with all stages of a building's life. Previous studies have shown the significance of the energy required for the operation of buildings as well as the energy embodied in initial building construction [6], [7], [8], [9]. Fewer studies have analysed the recurrent embodied energy involved in maintenance and refurbishment activities over a building's life [10], [11], [12], [13]. Recurrent embodied energy associated with the replacement of building materials and components is directly affected by the service life of building materials as well as the service life of buildings themselves. However, the significance of building service life and recurrent embodied energy on the life cycle energy of a building is not well understood. The aim of this study was to determine what effect variations to the service life of buildings has on their life cycle embodied energy demand. It was hoped that this would provide new evidence of the importance of integrating building service life considerations in the initial design process and facilities management phase, in order to select the most appropriate construction materials and methods to reduce energy demand over the building life cycle.

Section snippets

Life cycle energy analysis

The approach used to quantify the energy demand of a building across its life is known as LCEA (life cycle energy analysis). This approach is based on the general principles of LCA (life cycle assessment) as outlined in ISO 14040 [14] and is used to quantify the effects of a product or process on the environment during the different stages of its life cycle [15]. The system boundary for a life cycle energy analysis of a building typically includes the energy demand associated with the

Research approach

In order to determine what effect a variation in service life would have on the life cycle embodied energy demand of a residential building, the total life cycle embodied energy associated with a selected case study building was quantified. This involved calculating and combining the initial and recurrent embodied energy of the building. A number of building service life scenarios were developed and the life cycle embodied energy demand of the selected case study building was recalculated. The

Results and discussion

This section presents the results of the life cycle embodied energy analysis of the case study house for each of the building service life scenarios to demonstrate the effect of building service life variability on the life cycle embodied energy demand of a building.

Conclusion

This study aimed to determine what effect variations in the service life of buildings would have on their life cycle embodied energy demand. A case study house located in Melbourne, Australia was used for this analysis. The life cycle embodied energy of the house for a building service life range of 1–150 years over a period of 150 years was calculated using a comprehensive I–O-based hybrid assessment approach.

The study has shown that a variation in the service life of buildings can have a

Acknowledgements

The authors acknowledge the anonymous reviewers of previous versions of this paper and their contribution to improving the quality of the final paper.

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View full text

Building service life and its effect on the life cycle embodied energy of buildings

Highlights

Abstract

Introduction

Section snippets

Life cycle energy analysis

Research approach

Results and discussion

Conclusion

Acknowledgements

Energy

Energy

Build Environ

Energy Build

J Environ Manage

Energy

Energy

Build Environ

Energy Build

Buildings energy databook, 2006

Buildings and climate change: status, challenges & opportunities

The human impact on the natural environment: past, present, and future

Trends in atmospheric carbon dioxide – global

Harvesting the biosphere: the human impact

Popul Dev Rev

Australian residential building sector greenhouse gas emissions 1990–2010

Using national input-output data for embodied energy analysis of individual residential buildings

Constr Manag Econ

A comprehensive framework for assessing the life cycle energy of building construction assemblies

Archit Sci Rev

Life cycle energy analysis of buildings: a case study

Build Res Inform

The significance of embodied energy in certified passive houses

The relationship between material service life and the life cycle energy of contemporary residential buildings in Australia

Archit Sci Rev