Scenario analysis of embodied energy and CO2 emissions for multistory apartments in Indonesia

Graduate School of Advanced Science and Engineering, The University of Hiroshima, Hiroshima, Japan

^* Corresponding author: m220937@hiroshima-u.ac.jp

Abstract

Contribution in the building sector to the global warming can be tackled by diminishing greenhouse gas (GHG) emissions (mainly CO₂) not only from operational energy but also from the embodied energy (EE) of construction materials. Harvested Wood Products (HWP) such as Cross Laminated Timber (CLT), Glued Laminated (Glulam) timber, among others, make multistorey wooden buildings possible. These wooden buildings could help to reduce EE and CO₂ emissions significantly. A material flow analysis (MFA) using an I-O (Input-Output) table was used to compare three scenarios for an 8-story apartment building in Indonesia (total floor area: 9140 m₂): First, the building had a reinforced concrete structure. Second, the building had a “hybrid” structure with reinforced concrete cores and first-floor elements, consisting of CLT floor panels, and Glulam columns and beams. Third, the building used only CLT panels besides reinforced concrete cores. The results showed that the last scenario achieved the largest CO₂ emissions and embodied energy reductions (58 t-CO₂ and 905 GJ), compared with the first scenario (81 t-CO₂ and 1110 GJ). Furthermore, we compare two methods to apply displacement factors (DF) to assess the CO₂ emissions savings for each CO₂ ton in wood products substituted in place of non-wooden products between the three building scenarios.