A numerical framework for an electrically-charged PCM brick to reduce winter peak heating demand

Area of Science:

• Building Science
• Materials Science
• Energy Systems

Background:

• Cold climates face challenges with peak electrical demand for space heating, impacting grid stability and energy costs.
• Traditional building materials offer limited thermal regulation, leading to significant energy loss.
• Existing solutions often fail to adequately address the dynamic nature of heating demands during extreme weather.

Purpose of the Study:

• To propose and numerically investigate a novel active thermal energy storage system integrated into a building brick.
• To assess the system's performance in mitigating peak electrical demand for space heating.
• To enhance indoor thermal comfort and building energy resilience in cold climates.

Main Methods:

• Development of an active thermal energy storage brick incorporating Phase Change Material (PCM) and copper oxide foam.
• Coupling the PCM brick with a low-wattage electrical heating element for controlled charging and discharging.
• Utilizing computational fluid dynamics (CFD) modeling to simulate system performance under severe winter conditions (down to -30°C).

Main Results:

• The active PCM-brick maintained a surface temperature above +8°C, compared to -5°C for an unheated brick.
• Delivered a peak heat output exceeding 150 W/m² to the living space.
• Reduced the wall's net daily energy loss by nearly 70%, effectively shifting load from peak hours.

Conclusions:

• The active Phase Change Material (PCM) brick is a viable solution for peak-shaving in cold climates.
• The system significantly enhances occupant comfort and building energy resilience.
• This technology offers a substantial reduction in the burden on primary HVAC systems during peak demand periods.