24th Pacific Science Congress (PSC-24)

Rapid urbanization has intensified construction activity, driving higher resource consumption and environmental pressures in cities. Understanding how material flows, waste generation, and circular economy practices interact within the building sector is essential for developing effective regional sustainability strategies. This study applies an integrated modeling framework, combining dynamic material flow analysis, and prospective life cycle assessment, to assess the long-term trajectories of material stock, energy demand, and greenhouse gas (GHG) emissions in Hong Kong’s public rental housing (PRH) sector from 1950 to 2100. Results show that the PRH building stock expanded rapidly from the late 1970s and is anticipated to stabilize at around 49 million m² by 2050, marking a shift from large-scale construction to renewal and refurbishment. Energy demand is expected to rise until mid-century before stabilizing, while operational activities, especially diesel-based activities, dominate GHG emissions, which could be reduced by up to 50% by 2050 through partial decarbonization in material recycling and carbon capture. Ultimately, the findings contribute to scenario-based, region-specific modeling by balancing supply and demand in the construction sector and shaping policy interventions aimed at minimizing environmental impacts.
 

System dynamics model,Material flow analysis,Prospective life cycle assessment,Industrial ecology,Scenario analysis,Integrated assessment models