Multifunctional Radiative Cooling Geopolymer for Energy Saving in Buildings

Area of Science:

• Materials Science
• Sustainable Construction
• Building Physics

Background:

• The construction industry consumes ~40% of global energy, with Ordinary Portland Cement (OPC) production causing ~8% of CO2 emissions.
• Traditional building materials lack integrated thermal management and contribute significantly to environmental pollution.

Purpose of the Study:

• To develop and evaluate a multifunctional radiative cooling geopolymer (MRCG) as a sustainable building material.
• To assess MRCG's thermal insulation, radiative cooling performance, and structural integrity.
• To model potential energy savings and environmental benefits in buildings.

Main Methods:

• Synthesis of MRCG using an environmentally benign process.
• Characterization of thermal conductivity, compressive strength, fire resistance, solar reflectance, and mid-infrared emissivity.
• Modeling of energy savings in buildings under hot climate conditions.

Main Results:

• MRCG exhibits low thermal conductivity (0.31 W/(m·K)) and high compressive strength.
• Achieved solar reflectance >93% and mid-infrared emissivity >95% for daytime subambient cooling (~4.0 °C).
• Modeled energy savings of up to 23% in hot climates.

Conclusions:

• MRCG is a promising sustainable building material combining thermal insulation and radiative cooling.
• It offers significant potential for reducing HVAC energy demand and operational CO2 emissions.
• MRCG contributes to energy efficiency and carbon reduction goals in the construction sector.