A Critical Review on the Control Strategies Applied to PCM-Enhanced Buildings

Abstract

The incorporation of phase change materials (PCM) in buildings has the potential to enhance the thermal efficiency of buildings, reduce energy cost, shift peak load, and eventually reduce air pollution and mitigate global warming. However, the initial capital cost of PCM is still high, and thus the establishment of a control strategy has become essential to optimize its use in buildings in an effort to lower investment costs. In this paper, an extensive review has been made with regard to various control strategies applied to PCM-enhanced buildings, such as ON/OFF control, conventional control methods (classical control, optimal, adaptive, and predictive control) and intelligent controls. The advantages and disadvantages of each control strategy are evaluated. The paper further discusses the opportunities and challenges associated with the design of PCM-enhanced buildings in combination with control strategies.

Numerical Study of Heat Transfer Enhancement within Confined Shell and Tube Latent Heat Thermal Storage Microsystem Using Hexagonal PCMs

“…While a literature review demonstrates that PCM has several disadvantages, including phase separation, corrosion potential, leakage issues, supercooling, poor specific heat, and thermal conductivity, there are solutions available to alleviate or mitigate these disadvantages [ 19 , 20 , 21 , 22 , 23 , 24 ]. Using performance improvement approaches, the PCM’s phase transition rate, thermal conductivity, latent heat storage capacity, and thermo-physical stability are all enhanced.…”

Temperature Control to Improve Performance of Hempcrete-Phase Change Material Wall Assemblies in a Cold Climate

“…Latent heat storage systems with phase change materials (PCMs) are promising technology capable of storing and releasing significant quantities of heat per unit of mass through a phase change from liquid to solid and back near room temperature [1,2]. As a result, the PCM can better control indoor temperatures and save energy by absorbing part of a building's heat load during the daytime as it melts and releasing this heat during the cooler nighttime as it returns to its solid phase.…”

“…As a result, the PCM can better control indoor temperatures and save energy by absorbing part of a building's heat load during the daytime as it melts and releasing this heat during the cooler nighttime as it returns to its solid phase. In passive applications, PCMs are typically embedded into the building fabrics of walls, floors, roofs, fenestration, façade, shutter, and shading systems without relying on auxiliary equipment, which increases the envelope's thermal storage capacity [1,2]. PCM is integrated into the building fabrics through different approaches such as PCM-enhanced covering materials, including plasterboards, wallboards or gypsum boards [3][4][5], concrete [6,7], ceramics [8,9], microencapsulated PCM panels [10][11][12], multi PCM structure [13][14][15][16], and PCM-impregnated insulations [17][18][19].…”

“…PCM is integrated into the building fabrics through different approaches such as PCM-enhanced covering materials, including plasterboards, wallboards or gypsum boards [3][4][5], concrete [6,7], ceramics [8,9], microencapsulated PCM panels [10][11][12], multi PCM structure [13][14][15][16], and PCM-impregnated insulations [17][18][19]. The initial capital cost of PCM is still high [2,20]. Furthermore, PCM needs to undergo a phase change transition from solid to liquid and back to be fully effective.…”

“…Different control strategies have been used in buildings with PCM-enhanced envelopes to control the operation of the mechanical systems and hence ensure indoor comfort while minimizing energy consumption, cost, and CO 2 emissions [2]. Some studies investigated natural ventilation techniques alone or combined with HVAC setpoint control strategies to lower the cooling demand and discomfort time.…”