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D. Moudgil and V. Khullar
Nomenclature
English symbols
m
Mass
Tavg Average temperature
Tatm Atmospheric temperature
Subscripts
f
Fraction
Abbreviations
PCM Phase change material
NPs Nanoparticles
TES Thermal energy storage
OC
Optical charging
TC
Thermocouple
12.1 Introduction
In today’s world the energy demand in the industrial, household, agriculture and service sector vary on daily, weekly and seasonal basis. Thermal energy storage (TES)
provides a simple an economic means of utilizing solar energy even during nonsunshine hours to satisfy our growing needs for heating and cooling. TES essentially
involves three processes: charging, storage and discharging. Furthermore, thermal
storage process could be either sensible TES or latent TES. In sensible heat storage,
the material (concrete, rock, etc.) undergoes temperature change during charging and
discharging processes; whereas in latent TES, the material (ice, salts, etc.) undergoes phase transformation during the charging and discharging processes (Dincer
and Rosen 2002). Latent TES (employing PCMs) in particular offers range of capacities (quantity of energy stored) and capability of storing energy ranging from few
hours to a few days at relatively high energy stored to volume ratio. PCMs could
be classified into three basic types: organic (paraffins, fatty acids), inorganic (salt
hydrates), eutectics (organic, inorganic) (Paksoy 2007). Conventionally, the charging process (melting of PCM) involves bleeding a part of the heated fluid from the
D. Moudgil and V. Khullar
Nomenclature
English symbols
m
Mass
Tavg Average temperature
Tatm Atmospheric temperature
Subscripts
f
Fraction
Abbreviations
PCM Phase change material
NPs Nanoparticles
TES Thermal energy storage
OC
Optical charging
TC
Thermocouple
12.1 Introduction
In today’s world the energy demand in the industrial, household, agriculture and service sector vary on daily, weekly and seasonal basis. Thermal energy storage (TES)
provides a simple an economic means of utilizing solar energy even during nonsunshine hours to satisfy our growing needs for heating and cooling. TES essentially
involves three processes: charging, storage and discharging. Furthermore, thermal
storage process could be either sensible TES or latent TES. In sensible heat storage,
the material (concrete, rock, etc.) undergoes temperature change during charging and
discharging processes; whereas in latent TES, the material (ice, salts, etc.) undergoes phase transformation during the charging and discharging processes (Dincer
and Rosen 2002). Latent TES (employing PCMs) in particular offers range of capacities (quantity of energy stored) and capability of storing energy ranging from few
hours to a few days at relatively high energy stored to volume ratio. PCMs could
be classified into three basic types: organic (paraffins, fatty acids), inorganic (salt
hydrates), eutectics (organic, inorganic) (Paksoy 2007). Conventionally, the charging process (melting of PCM) involves bleeding a part of the heated fluid from the