An Input-Output-based Hybrid (IOH) Model for Computing Initial and Recurrent Embodied Energy of Residential and Commercial Buildings

Buildings consume approximately 48% of global energy each year in their construction and operation alone adding proportionally to global carbon emission. In order to optimize the energy and carbon footprint of a building, assessing its life cycle energy usage by incorporating embodied and operating energy is important. Embodied energy is the total energy embedded in a building’s construction, maintenance, replacement, and demolition. Embodied energy consumed through various products and processes used in a building’s initial construction is called initial embodied energy. When occupied, operating energy is consumed in operating the building throughout its life cycle in the processes of air-conditioning, heating, lighting, etc. While in use, the building also undergoes periodic maintenance, repair, and replacement activities further consuming recurrent embodied energy through the use of products and processes. For comprehensively assessing and optimizing total life cycle embodied energy both the initial and recurrent embodied energy must be quantified. Although a consensus is lacking in literature over which method is apt, an input-output-based hybrid (IOH) method is considered relatively complete. In this study, we use the latest input-output (IO) data and develop an IOH model for the United States’ economy to quantify the embodied energy intensity of residential and commercial sectors. The residential sector’s intensity is calculated for single and multi-family structures, whereas commercial sector’ intensity is quantified under the categories of healthcare, educational, and other commercial structures. We also calculate the recurrent embodied energy for residential and commercial sectors. Finally, we discuss and compare the calculated values with those reported by similar studies.

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