ArticlePDF Available

Abstract and Figures

Thermal energy storage systems (TES) are an effective technology to improve the energy efficiency while reducing the energy consumption in buildings. The integration of phase change materials (PCMs) as latent thermal energy is a popular method to incorporate them into the building envelope, reducing the energy demand and helping maintain the thermal comfort. In this experimental evaluation, the application of S23 ceiling panels to enhance the building performance is investigated. To analyse the PCM panels, a test room was artificially heated securing the melting temperature for the material; the results show that the S23 panels were able to absorb and increase the room temperature by 5 °C. During the cooling period, the PCM ceiling tiles help maintain higher room temperatures, up to +1.5 °C. The S23 panel temperature was able to drop below its melting point after 6 hours of cooling, demonstrating its capacity to complete the thermal cycle. The panel thermal conductivity range was found between 0.19–0.24 W/(m·K). It can be concluded that the addition of the S23 ceiling panels can be considered as an innovative solution for the application of passive TES in building envelopes, leading to energy savings by absorbing, storing and helping maintaining the ambient room temperature, therefore reducing the requirement for artificial heating and cooling.
Content may be subject to copyright.
1. Introduction
Worldwide energy demand has increased due to the
improvement of the living standards, this has led to a
growing interest in sustainable energy solutions that con-
tribute to a reduction in the CO2 emissions. In Europe,
the building sector represents 40% of the total energy
consumption and nearly 50% of this energy is utilized
for space heating and cooling. For this reason, improving
the building envelope is considered a suitable solution
to reduce the heating and cooling energy demand and
improve the thermal comfort (Marin et al., 2016). Ther-
mal energy storage (TES) is an effective method to reduce
the energy consumption, decreasing the on-peak load
and shifting it to off-peak periods. This technology helps
reduce the breach between the energy supply and energy
demand by storing the available energy and using it dur-
ing inaccessible periods (Kalaiselvam, Parameshwaran and
Harikrishnan, 2012; Zeinelabdein, Omer and Gan, 2018).
Thermal energy storage also known as heat and cold
storage can be stored in form of sensible heat (SHTES),
latent heat (LHTES), and thermochemical storage (TCES);
allowing the energy storage to be released when the
energy demand requires it (Mehling, 2008). The advan-
tage of this technology is that they operate at relative low
temperature range (within the human thermal comfort
temperatures), making them suitable for passive building
The main parameter for the sensible heat refers to the
specific heat capacity. This factor calculates the necessary
energy to increase 1 kg of the material to 1 °K. The sensi-
ble heat can be calculated as follows:
Q m Cp dT
– m= mass (kg)
– Ti= initial temperature (K)
– Tf= final temperature (K)
– Cp= specific heat capacity (J·kg K)
The latent heat considers the heat stored or released dur-
ing the phase change of the material. Throughout this
period, the temperature remains constant and at this
stage the material can absorb considerable energy quan-
tities. The total amount of energy is determined by the
enthalpy value and is measured during the material phase
transition as shown in the following equation:
Velasco-Carrasco, M, et al. 2020. Experimental Evaluation of Thermal Energy
Storage (TES) with Phase Change Materials (PCM) for Ceiling Tile Applications.
Future Cities and Environment,
6(1): 11, 1–11. DOI:
Department of Architecture and Built Environment, Faculty of
Engineering, University of Nottingham, UK
Corresponding author: Mariana Velasco-Carrasco
Experimental Evaluation of Thermal Energy Storage
(TES) with Phase Change Materials (PCM) for Ceiling
Tile Applications
Mariana Velasco-Carrasco, Ziwei Chen, Jorge Luis Aguilar-Santana and Saa Riat
Thermal energy storage systems (TES) are an eective technology to improve the energy eciency while
reducing the energy consumption in buildings. The integration of phase change materials (PCMs) as latent
thermal energy is a popular method to incorporate them into the building envelope, reducing the energy
demand and helping maintain the thermal comfort. In this experimental evaluation, the application of S23
ceiling panels to enhance the building performance is investigated. To analyse the PCM panels, a test
room was articially heated securing the melting temperature for the material; the results show that the
S23 panels were able to absorb and increase the room temperature by 5 °C. During the cooling period,
the PCM ceiling tiles help maintain higher room temperatures, up to +1.5 °C. The S23 panel temperature
was able to drop below its melting point after 6 hours of cooling, demonstrating its capacity to complete
the thermal cycle. The panel thermal conductivity range was found between 0.19–0.24 W/(m·K). It can be
concluded that the addition of the S23 ceiling panels can be considered as an innovative solution for the
application of passive TES in building envelopes, leading to energy savings by absorbing, storing and help-
ing maintaining the ambient room temperature, therefore reducing the requirement for articial heating
and cooling.
Keywords: building application; energy storage; phase change materials; thermal energy performance
Velasco-Carrasco et al: Experimental Evaluation of Thermal Energy Storage (TES) with Phase Change
Materials (PCM) for Ceiling Tile Applications
Art. 11, page 2 of 11
Qm h
D= D
– m= mass (kg)
Δh= enthalpy change (J · kg)
The utilization of phase change materials (PCMs) as latent
thermal energy are ideal for thermal management and
storage, due to their capacity to absorb, store and release
latent heat during the phase transition (Yang et al., 2020).
PCMs offer considerable advantages, such as high thermal
density and relatively constant phase transition tempera-
ture during the melting and solidification process. Never-
theless, the major factor affecting the PCM performance
correspond to the low thermal conductivity (Elmaazouzi et
al., 2020). The thermal conductivity (λ) refers to the capac-
ity of a given material to transfer heat while the material
remains static. In general, a material in solid state presents
higher thermal conductivity in comparison to the liquid
state due to the molecular interaction to transport heat
(Mehling, 2008).
The definition of λ (W/mK) is determined by Fourier’s
law, which is for 1-dimensional steady state heat conduc-
tion and is described as follows:
QA dx
PCMs can be classified as organics, inorganics and eutec-
tics. Some of the most popular inorganic PCMs are salt
hydrates, consisting of a mixture of salt and water in a dis-
crete mixing ratio. Generally, these water molecules are
paired with the salt molecules creating a crystal structure
(Mehling, 2008). Salt hydrates are characterized by their
high storage density with respect to the mass and volume.
The thermal conductivity of salts can be considered as
high and in general they are chemically stable. The major
drawback of salt hydrates is phase segregation, due to
their chemical composition consisting on of different
substances with variable densities.
The building envelope regulates the heat exchange
between outdoor and indoor environment, affecting the
energy requirements and human thermal comfort (Marin
et al., 2016). The incorporation of PCMs in buildings is
mainly achieve through the addition of the material into
structural components such as walls, windows, roofs or
ceilings and commonly they are applied as passive sys-
tems. Auxiliary components such as HVAC systems and
solar heating units can be coupled with PCMs. Adding
thermal mass into building elements helps to control any
abrupt temperature fluctuations, particularly in light-
weight structures; decreasing the overheating in summer
and preventing heat loss during winter (Skovajsa, Koláček
and Zálešák, 2016). Another advantage for the PCMs inte-
gration in the building structure is having a large surface
area directly in contact with the indoor environment,
therefore allowing an effective heat transfer.
PCM-TES has been extensively investigated prior 1980,
the implementation of PCM for energy conservation in
the building structure was first mentioned in 1975 by
Barkmann and Wessling (Barkmann and Wessling, 1975);
since then a considerable amount of research has been
developed (Iten, Liu and Shukla, 2016). Examples of
such technologies are PCM panels, PCM-enhanced walls,
nano-PCM, PCM windows, among others. Piselli et al.
investigated the performance of PCM for passive cool-
ing applications, finding that by integrating PCM into
the building envelope significant cooling savings were
achieved, generating a reduction up to 300 kWh/year for
mild climates in Italy (Piselli et al., 2020). Similarly, Kishore
et al. investigated the addition of PCM into the build-
ing walls, the results exhibited a reduction in the annual
heat gain and heat losses of 47.2% and 8.3%, respectively
(Kishore et al., 2020).
Alawadhi utilized PCM in the windows shutters to
reduce the building heat gain. The investigation aimed to
employ the PCM latent heat to avoid the heat entering
the building. The experiment tested n-Octadecane with a
melting temperature of 27 °C, n-Eicosane with a melting
temperature of 37 °C and P116 with a melting tempera-
ture of 47 °C, the results concluded that the PCM with
the highest melting temperature (47 °C) presented the
best thermal performance, obtaining heat gain reductions
up to 23.29% (Alawadhi, 2012). Sayyar et al. used experi-
mental and numerical approaches to evaluate the thermal
performance of a nano-PCM integrated in gypsum wall-
boards. The nano-PCM consisted of a fatty-acid PCM cou-
pled with graphite nano-sheets. The results show that the
control cell presented a temperature range from 13 °C to
32 °C. In contrast, the nano-PCM wall had a temperature
range from 18.5 °C to 26.5 °C; demonstrating the ability
of the PCM to reduce the indoor temperature fluctuations
(Sayyar et al., 2014). Voelker et al. studied the impact on
the room temperature of gypsum plaster and a salt mix-
ture; the study concluded that the utilization of phase
change materials in buildings increased the thermal mass
and contributed to an enhancement of the thermal pro-
tection during summer. Nevertheless, it was found that
the system could get oversaturated if the PCM was not
properly discharged after a few consecutive days. To coun-
teract such effect, the authors proposed the application of
a night ventilation system to facilitate the PCM full cycle
(Voelker, Kornadt and Ostry, 2008). Another study by
Saxena et al. analysed the performance of PCM embeded
bricks, finding a heat transfer reduction between 40 to
60% during daytime and a temperature reduction of 4.5
°C to 9.5 °C in comparison to conventional bricks (Saxena,
Rakshit and Kaushik, 2020).
Maleki et al. proposed the application of nano-capsules
containing PCM in the walls and roof plaster to boost
the thermal comfort. The results indicate that the PCM
system could reduce the indoor air temperature fluctua-
tions and help maintain indoor thermal comfort for most
of the year (Maleki et al., 2020). Qunli et al. developed a
cooling ceiling composed of an insulation layer, a mor-
tar embedded with the capillary pipes and a PCM layer.
The mathematical model concluded that the energy stor-
age ratio of the phase change energy storage system was
higher in comparison of a concrete ceiling (Qunli et al.,
2017). Ceiling tiles are a practical method to integrate
the PCMs into building structure, increasing thermal
mass, reducing temperature fluctuations, and assisting
Velasco-Carrasco et al: Experimental Evaluation of Thermal Energy Storage (TES) with Phase Change
Materials (PCM) for Ceiling Tile Applications
Art. 11, page 3 of 11
in energy performance by regulating the indoor tempera-
ture (Velasco-Carrasco et al., 2020). Memon et al. investi-
gated the thermal performance of lightweight aggregate
concrete (LWAC) containing macro encapsulated paraffin
in Hong Kong. The results of the indoor test revealed that
the macro encapsulated paraffin–LWAC panel was able
to decrease the interior indoor temperature by 2.9 °C,
flattening the temperature fluctuation. The outdoor test
found that the room temperature was optimized when
there was a considerable temperature difference between
day and night (Memon, Cui, Zhang, & Xing, 2015).
In this paper, the effects of integrating PCM ceiling tiles
to enhance the indoor thermal performance has been
experimentally investigated. The technology proposed
is based on a commercial PCM panel developed by PCM
Products Ltd© .The selected PCM was S23, which has a
melting point of 23 °C and possess a phase change range
compatible with the human thermal comfort tempera-
tures (22 to 26 °C in moderate climates), this allows the
use of the latent heat to improve the thermal inertia while
decreasing the energy consumption. The fundamental dif-
ference between standard solutions and the proposed
technology focuses on the encapsulation design, specifi-
cally tailored to promote the heat exchange between the
PCM and the ambient temperature. Numerous studies
of ceiling cooling systems with PCM have been studied.
Nonetheless, most of the research focuses on numerical
simulations, lacking real-scale testing.
2. Methodology
2.1 Experimental setup
The experiment was conducted in a testing room at The
University of Nottingham. The test room is allocated in a
Georgian period house part of the Architecture and Built
Environment Department. The testing room surface is 8.3
m2, with a height of 3.31 m; the room contains two win-
dows covering a surface area of 2.99 m2. The room has
brick walls with gypsum and paint finishing, with a total
thickness of 15 cm; the ceiling is formed out of concrete
with a thickness of 15 cm and the windows are single
glazed. For experimental purposes, the panels were placed
in the top section of a shelving system to represent the
ceiling hight as shown in Figure 1.
2.2 Materials
PlusICE S23 is a salt hydrate developed by PCM Products
Ltd© with a melting temperature of 23 °C, the thermal
properties are described in Table 1. The capsule material
depicted in Figure 2 consists of a rectangular plastic con-
tainer measuring 24 cm × 49 cm, the design contemplates
circular rings on the top and bottom in order to facilitate
the panel stacking when required. Each panel has a total
weight of 3.5 kg and for the experimental purposes a set
of 20 panels were manufactured, having a net PCM weight
of 52 kg that represents 28% of the ceiling area.
2.3 Thermal conductivity analysis
The thermal conductivity was measured using the HFM-
100 Heat Flow Meter method, in which two flux sensors
were utilized to measure the thermal conductivity and
thermal resistance. The equipment sensors have a thermal
conductive range between 0.005 to 0.5 W/(m·K) and the
temperature range of –20 °C to 70 °C. To validate the accu-
Figure 1: a) Testing room with PCM panels b) House layout, testing room in red (The University of Nottingham, 2020).
Table 1: PCM properties (PCM Products Ltd, 2020).
S23 properties Units
Phase change temperature 23 (°C)
Density 1,530 (kg/m3)
Latent Heat Capacity 200 (kJ/kg)
Specific Heat Capacity 2.20 (kJ/kgK)
Thermal Conductivity 0.54 (W/(m·K))
Velasco-Carrasco et al: Experimental Evaluation of Thermal Energy Storage (TES) with Phase Change
Materials (PCM) for Ceiling Tile Applications
Art. 11, page 4 of 11
racy of the measurement an expanded polystyrene board
was tested as a calibration material; furthermore, each test
was repeated three times to corroborate the results. As the
original panel exceeds the equipment dimensions a small-
scale sample was provided by the same manufacturer as
shown in Figure 3.
2.4 Room measurement equipment
The aim of this measurements was to determine the
change in the ambient temperature during the charging
and discharging process. The panels were charged using
radiators with a heat capacity of 2 kW and the room tem-
perature loss was monitored after ensuring the complete
charging of the PCM. The temperature measurements
were made using Type K thermocouples and all readings
were collected by the data logger (DT85), with a standard
deviation of ±0.3 °C. The sensors were placed in the four
walls, ceiling, floor, windows, radiators and inside the PCM
panel as shown in Figure 4, a total of 16 thermocouples
where placed inside the room and the average tempera-
ture was noted for the results analysis. In addition, 10 THD
sensors (EL-USB-2) were placed in the testing room, hav-
ing a standard temperature deviation of ±0.55 °C, 2.25%
for the relative humidity and 1.7 °C for the dew point.
Figure 2: PlusICE S23 panel (PCM Products Ltd, 2020).
Figure3: Thermal conductivity S23 sample panel.
Velasco-Carrasco et al: Experimental Evaluation of Thermal Energy Storage (TES) with Phase Change
Materials (PCM) for Ceiling Tile Applications
Art. 11, page 5 of 11
2.5 Measurement procedure
Figure 5 displays the shelving system with the PCM panels in
the testing room. The heating devices were switched on for
a minimum duration of 6 hours, thus heating up the room
and consequently the PCM panels. The heating temperature
exceed the enthalpy phase of the PCM, additionally the PCM
panels were visually inspected to verify the complete phase
transition to a full liquid state. After the heating phase, the
regeneration period was monitored, using the natural heat
loss to the ambient. The average room temperature without
PCM for the heating period was 27.6 °C.
The average temperature variation between the two
sensors was of –0.11 °C. The temperature comparison is
shown in Figure 6. The testing results present the average
temperature of both sensors.
3. Results and Discussion
3.1 Thermal conductivity analysis
The operational parameters of the thermal conductive
analysis are described in Table 2 and correspond to three
different mean temperatures, comparing the effect of
the phase transition (solid, transitioning, liquid). When
Figure 4: Testing room section with components.
Figure 5: Panels in shelving system.
Velasco-Carrasco et al: Experimental Evaluation of Thermal Energy Storage (TES) with Phase Change
Materials (PCM) for Ceiling Tile Applications
Art. 11, page 6 of 11
the test was performed at a solid state (mean tempera-
ture –10 °C), the thermal conductivity was found to be
0.19 W/(m·K), the lowest value recorded during the exper-
iment. In the second evaluation the mean temperature
was considered at 20 °C, in this temperature range the
panel had already started the phase transition and the
thermal conductivity was found at 0.23 W/(m·K). The
highest thermal performance was presented at a mean
temperature of 40 °C, at this stage the panel was fully
transition to a liquid state, having a thermal conductivity
of 0.24 W/(m·K).
According to the manufacturer data the thermal con-
ductivity of the S23 is 0.54 W/(m·K), this value is higher
than the obtained results and it is due to the encapsula-
tion material. In the case of the salt hydrates, their cor-
rosiveness reduce the encapsulation options, thus plastic
materials are an appealing solution (Velasco-Carrasco et
al., 2020). The importance of the container material is piv-
otal for the PCM to perform adequately in indoor environ-
ments and in this case, it is expected a slight reduction
from the plastic capsule in comparison to the natural ther-
mal conductivity of the PCM. Table 3 shows the thermal
conductivity of PCMs with similar melting temperatures
found on the literature for comparison purposes.
The thermal conductivity observed across the six sam-
ples exemplify the performance of the S23 in compari-
son to commercially available PCMs with similar melting
points. In this case, the S23 panel presents competitive
performance in comparison to pure PCM samples. These
results validate the application of the plastic capsule
container as an advantageous method for building
3.2 Room testing
Figure 7 represents a typical data recorded during the
heating and cooling period. The room was heated for a
duration of 6.8 hours, while the cooling period of had a
duration of 17 hours. The average room temperature dur-
ing the heating period was 26.3 °C and after the cooling
period was 16.3 °C with a final temperature of 15.2 °C.
Figure 8 shows the extended heating and cooling
period, having an average temperature of 27.6 °C and
19.5 °C respectively. It is seen that the room temperature
increased constantly during the heating period reaching
Figure 6: Room temperature heating comparison.
Table 2: S23 thermal conductive results.
PCM Mean Temperature
Upper Plate
Temperature (°C)
Lower Plate
Temperature (°C)
TC (W/(m·K)) Thickness
S23 –10 –20 0 0.19 30.8 0.388
S23 20 10 30 0.23 30.8 0.388
S23 40 30 50 0.24 30.8 0.388
Velasco-Carrasco et al: Experimental Evaluation of Thermal Energy Storage (TES) with Phase Change
Materials (PCM) for Ceiling Tile Applications
Art. 11, page 7 of 11
a maximum temperature of 30.0 °C, after the radiator is
swich off the temperature starts to decrease and the PCM
panels are not able to retain the room heat, reaching 16.6
°C after 35 hours. This can be attributed to the tempera-
ture difference between the indoor and outdoor environ-
ment during the test day, having an ambient temperature
range between 4 °C to 6 °C.
3.2.1 Melting process
The PCM effect over the room temperature can be
observed in Figure 9. The heating period shows the
progress of the increasing temperature, both with and
without PCM panels. This graph represents four different
testing days, one without PCM and the remnant having
the S23 panels allocated in the room. The graph presents
the radiator temperature and room average temperature.
It is possible to see that for a day without PCM the radiator
temperature corresponding to the top line achieve higher
temperatures in comparison to the PCM testing days; in
contrast the average room temperature presented the
lowest ambient temperature. When the PCM panels are
present, the radiator temperature tends to decrease after
2.5 hours, meaning that the panels are being charged and
therefore reducing the heating temperature; this factor is
proved by the average room temperature increment. The
maximum room temperature of the testing room without
PCM was 24.4 °C and 30.7 °C for the room with the S23
Table 4 presents the numerical results of the heating
experiment. The results show the average temperature
representing each of the values presented in Figure 9. It
can be noticed that the addition of the PCM decrease the
heating temperature, creating a minimum temperature
difference of 4.8 °C. Consequently, the is a rise in the aver-
age room temperature with the PCM, having a minimum
temperature difference of 1.9 °C. These results lead to the
Table 3: PCM thermal conductivity comparison.
PCM Melting
Temperature (°C)
Liquid [W/(m·K)] Solid [W/(m·K)] Reference
Paraffin C13–C24 22–24 0.21 (Cabeza et al., 2011)
RT22 22 0.20 0.20 (Rubitherm GmbH, 2020)
RT24 24 0.20 0.20 (Rubitherm GmbH, 2020)
RT 25 25 0.17 ± 0.01 0.19 ±0.01 (Weinläder, Beck and Fricke, 2005)
S27 27 0.48 ±0.04 0.79 ± 0.03 (Weinläder, Beck and Fricke, 2005)
L30 30 0.56 ± 0.03 1.02 ± 0.05 (Weinläder, Beck and Fricke, 2005)
Figure 7: Room temperature monitoring.
Velasco-Carrasco et al: Experimental Evaluation of Thermal Energy Storage (TES) with Phase Change
Materials (PCM) for Ceiling Tile Applications
Art. 11, page 8 of 11
Figure 9: Room temperature heating comparison.
Figure 8: Room temperature monitoring heating and cooling.
Table 4: Average temperature comparison results.
A) without PCM B) with PCM C) with PCM D) with PCM
65.0 22.9 58.0 24.8 60.2 28.2 56.3 28.3
ΔT –6.9 +1.9 –4.8 +5.3 –8.7 +5.3
Velasco-Carrasco et al: Experimental Evaluation of Thermal Energy Storage (TES) with Phase Change
Materials (PCM) for Ceiling Tile Applications
Art. 11, page 9 of 11
conclusion the 20 PCM ceiling tiles were able to increase
the room temperature level by 5 °C.
3.2.2 Solidication process
The cooling mode measurements show the freezing
progress of the PCM panels. It is possible to observe the
effect of the room temperature when compared to the
room without PCM. The heating devices were active for a
24-hour period, thus heating up the room. After this time-
lapse, the radiator was swich off and the monitoring period
started for 24 hours as seen in Figure 10. The graph pre-
sents higher room temperatures when the PCM panels are
allocated in the room, this factor is clearly marked for the
first 20 hours. After this period both temperatures appear
to reach similar values, however the room temperature
with the PCM ceiling tiles remains higher throughout the
test. The starting temperature for the room without PCM
was 34.3 °C and the end temperature 17.2 °C. In contrast,
the S23 room temperature started at 36.7 °C and the pre-
sented an end temperature of 17.4 °C.
The numerical results obtained from the analysis of
Figure 10 are displayed in Table 5. For the PCM room
it can be observed that the room temperature dropped
to 14.6 °C during the first 6 hours, reaching a room
temperature of 22.1 °C which is below the PCM melting
point. These results show the ability of the PCM to start
the regeneration process after 6 hours, allowing the ther-
mal cycle process to be completed over a 24-hour period.
This study aims to support the application of PCM tech-
nologies as a passive alternative to generate energy saving,
hence improving the building energy performance. The
experiment has been used to explore the effect of adding
insulation to the building envelope, its operating prin-
ciple is based on storing the available heat through the
melting process of the PCM and discharge it into the room
space. The tested system has demonstrated the potential
to provide energy savings, by reducing the peak indoor
temperatures and therefore reducing the energy opera-
tion requirements for heating and cooling.
In this case, the S23 panel performance presents favour-
able results for building incorporation, as the panel is suit-
able to securely contain the PCM and at the same time
promote the heat exchange interaction with the thermal
environment. Due to the corrosive nature of the S23, a
plastic encapsulation was adopted as a feasible solution.
The main findings of this paper are as follows:
Figure 10: Room temperature cooling comparison.
Table 5: Results average temperature comparison.
(Time-lapse) Start 6 (hr) 12 (hr) 18 (hr) 25 (hr)
A) Without PCM (°C) 34.3 20.5 18.5 17.9 16.9
B) With PCM (°C) 36.7 22.1 19.6 18.3 17.1
ΔT –2.4 –1.5 –1.1 –0.4 –0.2
Velasco-Carrasco et al: Experimental Evaluation of Thermal Energy Storage (TES) with Phase Change
Materials (PCM) for Ceiling Tile Applications
Art. 11, page 10 of 11
1. The thermal conductivity was found 0.19–0.24
W/(m·K), the S23 panel presents competitive per-
formance in comparison to “pure” PCM materials,
this confirms the application of the plastic capsule
container as an advantageous method for building
2. Adding the S23 panels decrease the heating tem-
perature and as a result the average ambient tem-
perature increased. This leads to the conclusion that
having 20 PCM ceiling panels created an impact in
the room temperature of 5 °C.
3. For cooling purposes, the S23 maintained higher
room temperatures in comparison to the room with-
out PCM. After a 6-hour period, the PCM panels tem-
perature drop below its melting point; indicating
the ability of the panel to cool down favouring the
completion of the thermal cycle.
4. Phase segregation was observed during the melting
period, a reduction in the panel dimensions would
be advisable to counteract this drawback.
5. It is pivotal to ensure that the adequate climate
conditions are provided for the specific PCM melt-
ing temperature, to ensure the completition of the
thermal cycle.
From the above results, it can be concluded that the addi-
tion of the S23 ceiling panels can be considered as an
innovative solution, having the potential to be considered
as passive TES, leading to energy savings by reducing the
energy demand thought storing the available energy and
releasing the heat to the environment at inaccessible peri-
This work was supported in part by the Science and Tech-
nology Council of Mexico (Consejo Nacional de Ciencia y
Tecnología, CONACYT).
Competing Interests
The co-author Saffa Riffat is the Editor in Chief of this
journal and was removed from all editorial duties involv-
ing the review and processing of this submission.
Alawadhi, EM. 2012. Using phase change materials
in window shutter to reduce the solar heat gain.
Energy and Buildings, 47: 421–429. Elsevier B.V. DOI:
Barkmann, HG and Wessling, FC. 1975. Use of building
structure components for thermal storage, in: Pro-
cessing of the Workshop on Solar Energy Storage
Subsystems for Heating and Cooling of Building,
Charlottesville, VA, USA.
Cabeza, LF, Castell, A, Barreneche, C, De Gracia, A
and Fernández, AI. 2011. Materials used as PCM
in thermal energy storage in buildings: A review.
Renewable and Sustainable Energy Reviews, 15(3):
1675–1695. Elsevier Ltd. [Online]. DOI: https://doi.
Elmaazouzi, Z, El, M, Gounni, A and Ghali, E. 2020.
Thermal energy storage with phase change mate-
rials: Application on coaxial heat exchanger with
fins. Materials Today: Proceedings, 3095–3100. Else-
vier Ltd. [Online]. DOI:
Iten, M, Liu, S and Shukla, A. 2016. A review on the air-
PCM-TES application for free cooling and heating
in the buildings. Renewable and Sustainable Energy
Reviews, 61: 175–186. Elsevier. DOI: https://doi.
Kalaiselvam, S, Parameshwaran, R and Harikrishnan,
S. 2012. Analytical and experimental investigations
of nanoparticles embedded phase change materials
for cooling application in modern buildings. Renew-
able Energy, 39(1): 375–387. Elsevier Ltd. [Online].
Kishore, RA, Bianchi, MVA, Booten, C, Vidal, J and
Jackson, R. 2020. Optimizing PCM-integrated walls
for potential energy savings in U.S. Buildings. Energy
and Buildings, 226. Elsevier Ltd. DOI: https://doi.
Maleki, B, Khadang, A, Maddah, H, Alizadeh, M,
Kazemian, A and Ali, HM. 2020. Development
and thermal performance of nanoencapsulated
PCM/ plaster wallboard for thermal energy storage
in buildings. Journal of Building Engineering, 32:
101727. Elsevier Ltd. DOI:
Marin, P, Saffari, M, de Gracia, A, Zhu, X, Farid, MM,
Cabeza, LF and Ushak, S. 2016. Energy savings
due to the use of PCM for relocatable lightweight
buildings passive heating and cooling in different
weather conditions. Energy and Buildings, 129: 274–
283. Elsevier B.V. DOI:
Mehling, H. 2008. Heat and cold storage with PCM an up to
date introduction into basics and applications, Heat
and mass transfer (Ed). Berlin; London: Springer.
PCM Products Ltd. 2020. PlusICE Range. [Online]. Avail-
able at: [Accessed 22 July
Piselli, C, Prabhakar, A, de Gracia, A, Saffari, M,
Pisello, AL and Cabeza, LF. 2020. Optimal control
of natural ventilation as passive cooling strategy
for improving the energy performance of build-
ing envelope with PCM integration. Renewable
Energy, 162: 171–181. Elsevier Ltd. DOI: https://doi.
Qunli, Z, Chaohui, Y, Yinlong, L and Hongfa D. 2017.
Simulation Research on the Thermal Performance of
the Cooling Ceiling Embedded with Phase Change
Material for Energy Storage. Energy Procedia,
105: 2575–2582. DOI:
Rubitherm GmbH. 2020. [Online]. Available at: https://
egory/organische-pcm-rt [Accessed 28 July 2020].
Velasco-Carrasco et al: Experimental Evaluation of Thermal Energy Storage (TES) with Phase Change
Materials (PCM) for Ceiling Tile Applications
Art. 11, page 11 of 11
Saxena, R, Rakshit, D and Kaushik, SC. 2020 .Experi-
mental assessment of Phase Change Material (PCM)
embedded bricks for passive conditioning in build-
ings’. Renewable Energy, 149: 587–599. Elsevier Ltd.
Sayyar, M, Weerasiri, RR, Soroushian, P and Lu, J.
2014. Experimental and numerical study of shape-
stable phase-change nanocomposite toward
energy-efficient building constructions. Energy and
Buildings, 75: 249–255. Elsevier B.V. DOI: https://
Skovajsa, J, Koláček, M and Zálešák, M. 2016. Thermal
energy storage in the form of heat or cold with using
of the PCM-based accumulation panels. [Online]. DOI:
The University of Nottingham. 2020. Built Environ-
ment Workshop. [Online]. Available at: https://
accessplans/1432aa.pdf [Accessed 11 May 2020].
Velasco-Carrasco, M, Chen, Z, Aguilar-Santana, JL and
Riffat, S. 2020. Experimental evaluation of phase
change material blister panels for building appli-
cation. Future Cities and Environment, 6(1): 1–7.
[Online]. DOI:
Voelker, C, Kornadt, O and Ostry, M. 2008. Tempera-
ture reduction due to the application of phase
change materials. Energy and Buildings, 40(5):
937–944. DOI:
Weinläder, H, Beck, A and Fricke, J. 2005. PCM-facade-
panel for daylighting and room heating. In: Solar
Energy, 78(2): 177–186. 1 February 2005. Perga-
mon. [Online]. DOI:
Yang, H, Wang, S, Wang, X, Chao, W, Wang, N, Ding,
X, Liu, F, Yu, Q, Yang, T, Yang, Z, Li, J, Wang, C
and Li, G. 2020. Wood-based composite phase
change materials with self-cleaning superhydro-
phobic surface for thermal energy storage. Applied
Energy, 261(January): 114481. Elsevier. [Online].
Zeinelabdein, R, Omer, S and Gan, G. 2018. Criti-
cal review of latent heat storage systems for free
cooling in buildings. Renewable and Sustainable
Energy Reviews, 82(May 2016): 2843–2868. Else-
vier Ltd. [Online]. DOI:
How to cite this article: Velasco-Carrasco, M, Chen, Z, Aguilar-Santana, JL and Riat, S. 2020. Experimental Evaluation of Thermal
Energy Storage (TES) with Phase Change Materials (PCM) for Ceiling Tile Applications.
Future Cities and Environment,
6(1): 11, 1–11
Submitted: 17 August 2020 Accepted: 20 November 2020 Published: 15 December 2020
Copyright: © 2020 The Author(s). This is an open-access article distributed under the terms of the Creative Commons
Attribution 4.0 International License (CC-BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium,
provided the original author and source are credited. See
Future Cities and Environment,
is a peer-reviewed open access journal published by
... Operation time of the air conditioning system was increased during the night as a result of floor integration of PCM. The Ceiling with PCM: Several researchers developed PCM based ceilings or ceiling panels for thermal management in buildings [127][128][129][130][131][132][133]. They proposed different materials and techniques. ...
... A weekly saving of 72% in energy was noted during the experiment in a test hut. PCM integrated ceiling panels used for thermal energy storage was labelled in the works of Jaworski et al. [130] and Velasco-Carrasco et al. [131]. To enhance the convective heat transfer in the ceiling, Yan et al. [132] used a mini channel with metal nanoparticles. ...
The prime concern of the scientific community nowadays is high energy consumption and related greenhouse gas (GHG) emission. One of the major energy consumers is building sector, where nearly 30% of total energy is disbursed, with high priority to space cooling and ventilation. In addition, the contribution of buildings for GHG emission is also high. Various researchers in the recent past have suggested and successfully implemented different cooling methods to address this crisis. This paper evaluates various models suggested by researchers for building cooling with phase change materials (PCMs). Since the exposed area of high-rise buildings is more, there is a great chance for energy savings. The PCM impregnated building wall and building brick models have the promising potential for energy saving, by providing thermal comfort and conceding the peak temperature. This article emphasises the wall and building brick applications of PCM for building cooling, that illuminate the associated difficulties and possible alternatives. From the study, it was found that the PCM walls can be constructed with different techniques like adding PCM as a separate layer or inserting PCM in brick holes. In some cases, the PCM is added as a constituent in the cement mortar for plastering or for making concrete. These techniques will help to reduce the building cooling load, peak heat flux, and shift the peak temperature to off working hours. In cooling applications, it is preferred to keep the PCM layer near the heat source for better performance. The performance of a PCM wall highly depends upon the type of PCM used, location of PCM in the wall, type of application, and on the phase transition temperature of PCM.
... In such cases, PCM can be most effective as they have high volumetric heat capacity at the time of phase transition, and it could be 30 times higher than that of concrete or other massive construction materials [5]. The melting temperature, thermal conductivity and Thermal Energy Storage (TES) density are the best measures to test the thermal performance of PCM's integration into buildings [26]. PCM with rapid melting and crystallization/solidification points are suitable for TES applications [3]. ...
Full-text available
Tropical region such as Darwin has similar weather patterns throughout the year, thus creating higher energy demands in residential buildings. Typically, buildings consume about 40 per cent of the total energy consumption for indoor heating and cooling. Therefore, building envelopes are linked with design strategies such as the use of thermal energy storage and phase change materials (PCM) to minimize this energy consumption by storing a large amount of thermal energy. Primarily, PCMs are targeted by researchers for use in different components of buildings for thermal efficiency; thus, this study aimed to provide a suitable PCM to optimize indoor thermal comfort and minimize the cooling loads of residential buildings in tropical climates through simulation of a tropical climate building and provide optimum thickness for the selected material. Microencapsu-lated PCM mixed with gypsum in wallboards were used to reduce the cooling load of a building located in Darwin. The cooling load of the building was calculated using Revit software. A comparison of the cooling load of the building was carried out using PCM-incorporated wallboards of thicknesses of 0 cm, 1 cm and 2 cm in Energy Plus software. The total cooling load decreased by 1.1% when the 1-centimetre-thickness was applied to the wall, whereas a 1.5% reduction was obtained when a 2-centimetre-thick PCM layer was applied. Furthermore, the reduced cooling loads due to impregnation of the PCM-based gypsum wallboard gave reduced energy consumption. Ultimately , the 2-centimetre-thickness PCM-based gypsum wallboard gave a maximum reduction in cooling load with a 7.6% reduction in total site energy and 4.76% energy saving in USD/m 2 /year.
... In these applications, melting temperatures of PCMs vary from 19 • C to 29 • C [11]. Velasco-Carrasco et al. [12] experimentally investigated the use of PCM in ceiling tiles for enhancing the building thermal performance. They used hydrated salt PCM with 23 • C melting temperature. ...
Full-text available
This study presents an experimental investigation into a novel incorporation of chilled ceiling with transparent membrane cover and phase-change material (PCM) to form a new type of PCM chilled ceiling panel. The membrane cover is infrared transparent to facilitate radiant cooling, but serves as a barrier of convection to avoid moisture condensation for applications in humid climate regions. As reliable electricity supply is still not accessible to millions of people, especially in sub-Saharan and South Asian countries where these countries also face the combined problems of high cooling demand and inadequate power supply, the use of solar energy would help to overcome these problems. To address such problems, the proposed PCM chilled ceiling can be applied along with a solar photovoltaic (PV) directly driven vapour-compression cooling system. Electricity generated by the photovoltaic (PV) panels drives the variable speed direct current (DC) compressor for cooling production, while excessive cooling is stored in the PCM packs for use at night. The variable speed compressor can adjust to match fluctuation in solar radiation and hence increases the utilization of solar energy. A small-scale experimental setup was prepared using a mini DC compressor refrigeration system. Integration of salt hydrate type PCM in chilled beam and chilled ceiling, respectively, and application of transparent membrane cover in chilled ceiling were tested to verify the proposed design.
Full-text available
In this work, the application of a PCM cooling system for hot climate applications is investigated. A novel design proposes the utilization of PCM panels to reduce the energy demand on an air-cooling system by absorbing a proportion of the thermal load. The system not only contemplates the application of the S27 PCM panels for indoor cooling but also considers a PCM-TES box to enhance the cooling performance. The experimental evaluation focused on two operating schedules, during daytime the environmental temperature was considered at 30°C, and at night-time, the temperature was reduced to 25°C. The results found an indoor average temperature difference of 1.8°C with the addition of the PCM panels. In terms of energy savings, the chiller energy consumption was positively impacted as the PCM reduced the operational time.
Full-text available
Phase Change Materials (PCMs) are characterised by their capacity to absorb available thermal energy, store it, and passively release it by utilizing latent heat during phase change, thus reducing temperature peaks and improving thermal comfort. This paper experimentally investigates the feasibility of a novel blister PCM panel for ceiling tile applications. Experimental panels enhance the thermal conductivity of the PCM with the addition of steel and aluminium wool particles at 3.77 wt.% and 23 wt.%, respectively. During the experimental procedure, the blister panels where able to absorb the heat coming from the environmental chamber, proving that the encapsulation material was able to promote the heat exchange. Furthermore, the PCM enhancement indicates that both the aluminium and steel wool particles improved the blister panel thermal performance. These results were confirmed by thermal conductive, calculated at 0.733 W/(m K) for the base panel, 0.739 W/(m K) for the aluminium wool, and 0.784 W/W/(m K) for the steel wool. The experiment suggest that the application of PCM blister ceiling tiles can be considered as an innovative method for thermal performance control and energy saving.
Full-text available
A radiant cooling ceiling which is embedded with capillary pipes and phase change material to store and supply cool was put forward. The mathematical model of such cooling ceiling which runs intermittently was set up to analyze its thermal performance. The influence of phase change material thermal storage performances on the average heat flux and energy storage ratio of the cooling ceiling was analyzed. The main factors affecting the thermal performance of the ceiling was obtained by sensitivity analysis. The cooling storage performance differences between the ceiling embedded with phase change material and the concrete ceiling were comparatively analyzed. The research results show that the energy storage ratio of the phase change energy storage ceiling is higher than that of the concrete ceiling.
Full-text available
This article describes the usage of thermal energy storage in the form of heat and cold with an adaptation of the special device which is composed of the thermal panels. These panels are based on the phase change materials (PCM) for normal inner environment temperature in buildings. The energy for the thermal energy storage is possible to get from built-in electric heating foil or from the tube heat exchanger, which is build in the thermal panels. This technology is able to use renewable energy sources, for example, solar thermal collectors and air-to-water heat pump as a source of heat for heating of the hot water tank. In the cooling mode, there is able to use the heat pump or photovoltaics panels in combination with thermoelectric coolers for cooling.
The Phase Change Material (PCM) integrated in building envelope can decrease the energy requirement for maintaining thermal comfort by enhancing the thermal energy storage of the wall and the roof. This work deals with experimental study of the thermal behavior of new plaster composite containing a nanoencapsulated PCM. Nanocapsules containing phase change material (NPCM) n-dodecanol as core and polymethyl me*thacrylate (PMMA) and CuO nanoparticles as shell were synthesized by miniemulsion polymerization and characterized by using FTIR, SEM, TEM, DSC, TGA and laser particle diameter analyzer. The average diameter of PCP was 195 nm, and the latent heat of phase change and encapsulation efficiency were 148.88 J/g and 72.28%, respectively. The Plaster - NPCM composites were produced in this project using compression molding and their effective thermal conductivity, latent heat and apparent specific heat were investigated. The addition of the PCM to the wall can enhance the heat storage in the wall. CuO consisted nanocapsules exhibited better thermal stability and conductivity and reliability determined by thermal cycling analysis. Reduce-scale test cells, (including room 1 without PCM wallboard and room 2 PCM wallboard) were compared to study the thermal performance of the PCM contained wallboard in passive systems. The results indicate that the PCM system can narrow indoor air temperature fluctuations and maintain indoor thermal comfort at most of the time of the year. The results demonstrate the suitability of incorporating nanoencapsulated PCM into plaster.
Phase Change Materials have been acknowledged for their potential to be used as passive strategy for improving energy efficiency and occupants’ thermal comfort in buildings. However, their performance still needs to be enhanced to have them effectively used. In this view, this study investigates the potential improvement of PCMs performance for passive cooling application by efficient natural ventilation in residential building stock. Therefore, coupled dynamic simulation and optimization analysis is performed to explore the optimum melting temperature of PCM integrated in the external building envelope to minimize cooling loads in different Italian climate zones. Moreover, various natural ventilation control strategies are implemented to assess their influence on the process of PCM charge-discharge cycle. Results show that PCM inclusion in the building envelope provides significant cooling savings, up to about 300 kWh/year in mild climates. Furthermore, both night and temperature controlled natural ventilation are able to enhance the efficiency of PCMs thermal energy storage charge-discharge cycle. However, the optimum performance is obtained by coupling PCMs with natural ventilation controlled by indoor/outdoor temperature difference in all considered climate contexts. Accordingly, considerable building cooling energy need reduction is achievable through the optimum combination of PCMs and natural ventilation control, especially in milder climates.
Buildings in the United States account for nearly half of total U.S. energy use. The energy used for space conditioning can be reduced by utilizing thermal energy storage, such as phase change materials (PCMs), into building envelopes; however, the energy savings of PCM-integrated building envelopes reported in the literature vary widely. In the absence of established guidelines, thermophysical requirements of an optimal PCM, its method of application into the building envelope, and the corresponding energy savings under various climates remain unknown. In this study, we perform an extensive numerical investigation on the integration of PCM into building walls to establish the key conditions required for effective utilization of PCM in reducing heat gains in the cooling season and heat losses in the heating season. We also determine the optimal transition temperature, optimal PCM location in the wall, and the energy-saving potential of the PCM-integrated building walls in five U.S. cities located in different International Energy Conservation Code climate zones. Results show that employing PCMs in building walls does not always lead to an improvement; in fact, incorrect applications of PCMs can substantially increase energy use in the buildings. In the climates we studied, PCMs were found effective in reducing heat gains during the cooling season while mostly ineffective in managing heat losses during heating season. Depending on the climate, optimized PCMs in U.S. building walls can provide reduction in the annual heat gain in the range of 3.5% to 47.2% and the annual heat loss in the range of -2.8% to 8.3%. Future consideration of buildings with substantial solar gains in winter may lead to more reduction in heat losses by PCMs.
For storing energy in thermal form, there are three types of storage: sensible heat storage (SHS), latent heat storage (LHS), and thermochemical storage (TCS). In the third millennium, LHS technology has been the most attractive technology for researchers and specialists, because of its enormous storage density compared to sensitive storage (high energy storage density, greater than 100 kJ/kg) in a small temperature range. Nevertheless, due to the low thermal conductivity of phase change materials (PCM), the thermal performance of the LHTES system is generally unsatisfactory. Therefore, this study highlights the role of annular fins on coaxial heat exchanger LHTES with annular fins, examined using software Comsol Multiphysics based on the finite element method. The present investigation is only for the process of charging. DelcoTerm is used as heat transfer fluid (HTF), and NaNO2-NaNO3 is used as PCM. In fact, the results show that the coaxial system with annular fins has a significant effect on the charging time compared to the reference case without fins. As the number of fins increases, the performance of LHTES increases.
The composites own super-hydrophobicity and thermal energy storage capacity. • The composites further prevent liquid leakage of TD in humid environment. • The composites could improve energy storage capacity in humid environment. • The composites with self-cleaning have efficient solar-to-thermal energy storage. A B S T R A C T Form-stable composite phase change materials, as thermal energy storage technology, show great promise for reducing energy consumption and relieving current energy shortage problems. However, porous supporting materials and most phase change materials are hydrophilic and hygroscopic, which cause crack-formation at the interfaces between supporting materials and phase change materials and decrease in thermal energy storage capacity of composite phase change material in wet or humid environment. There are almost no reports concerning this topic. Herein, form-stable and superhydrophobic composite phase change materials are fabricated by spraying superhydrophobic coating on the surface of composite phase change materials, in which delignified wood acts as a supporting material to protect against liquid leakage of 1-tetradecanol. The superhydrophobic composite phase change materials possess large water contact angle of 155° and superhydrophobic stability at 20-100 °C and pH 3-12, which prevents supporting materials and phase change materials from contacting with moisture in wet environment. In addition, the superhydrophobic composite phase change materials exhibit large latent heat of fusion (125.40 J/g), 29.58 J/g higher than that of composite phase change materials without superhydrophobic coating in wet environment. Moreover, the superhydrophobic composite phase change materials possess excellent thermal reliability and stability, efficient solar-to-thermal energy conversion and self-cleaning property, which are potential in the application of advanced energy-related devices and systems for thermal energy storage in wet or humid environment.
This study aims at providing a formidable solution to rapid increasing building energy demands. It projects Phase Change Material (PCM) incorporated bricks as a passive solution for cooling load abatement. The PCMs for this research are selected based on their thermal characteristics through Differential Scanning Calorimeter (DSC) and climatic conditions of the place. In this study, the experimental testing of PCM bricks under actual conditions, followed by, assessing the impact of various PCM configurations is carried out. The experiments are carried out for peak summer conditions, with ambient temperature above 40 °C, during the day. The temperature reduction of 4 °C–9.5 °C is observed across single and dual PCM layer bricks, compared to the conventional ones. The heat transfer reduction between 40% and 60% is observed, during the day. These bricks are also used to determine the effect of increasing the PCM thickness and using it in combination with fins, to assess the impact in terms of temperature and heat transfer to the inside surface. However, the results showed that using fins has a detrimental impact on temperature and heat flow.
Buildings have a major contribution to the global energy consumption. Heating, ventilating and air conditioning systems (HVAC) are responsible for most of the energy use in buildings. Thus, clean and sustainable alternatives such as free cooling of buildings have recently gained much attention as means to reduce the operation hours and capacity of the conventional cooling and heating systems. The free cooling could be provided by collecting the natural cold energy during night time in appropriate thermal storage form and this could be retrieved when needed. Phase change materials are exploited by a number of investigators as a storage medium in free cooling applications, as these substances possess high energy densities, and absorb and release heat at a narrow temperature range, hence, the comfort temperature can be maintained day and night. The objectives of this article are to provide a comprehensive review on recent development on free cooling technologies incorporating latent heat storage and to shit lights on the most significant parameters affecting the performance of these materials in free cooling strategy. The outcomes of this review would be helpful in providing clear insight information on potential improvements that can be applied to the storage materials. All the reviewed studies demonstrated that the night cooling strategy using PCMs has the capacity to maintain the indoor temperature well within the comfort zone whilst providing a considerable reduction in cooling loads in all considered climates.