The Life Cycle Cost-Energy Relationship of Buildings.

Abstract

Buildings account for nearly 45% of the worldwide energy consumption and carbon emissions, and play a vital role in formulating sustainable strategies. Many regions and countries have set targets to achieve low or zero energy in their building energy policies. However, despite the policy drive, the uptake of low energy building (LEB) has been low in practice. Previous research on LEB was largely technical solutions oriented. Some examined the impacts of low energy design solutions on the economic effectiveness and energy efficiency of the building over the building’s lifespan, but there is still a lack of exploration of the embedded relationship between the cost and energy performance of buildings. The aim of this paper is to explore the relationship between the costs and energy consumption of buildings from the life cycle perspective. A combination of a critical literature review and case studies of 5 residential buildings selected from UK and Australia was employed for the research. The results of the review suggest that there is second order polynomial regression relationship between the costs and energy consumption of buildings over their lifespans. The optimizations of the cost and energy efficiency of buildings are found to be not mutually exclusive goals, which need to be considered in a synergistic way in order to allow low energy designs and construction practices to be achieved cost-effectively. The findings should inform designers in their decision-making on building design and material selection to make LEB more cost attractive. The identified life cycle cost-energy relationship contributes a novel life cycle perspective to future systemic research into building energy and economics.