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industry [1]. High-temperature TES is especially suitable to be integrated into concentrating solar power (CSP) plants to solve the mismatch between energy supply
and demand. Since 2006, operators have built TES systems into CSP plants almost
exclusively using sensible heat for heat storage [2].
In the TES system, the design of the storage configuration depends on the scaled
capacity and storage media. Therefore, for a given scale of storage capacity, TES
media with higher heat capacity can reduce the amount of materials required,
resulting in smaller size of storage tanks and less pumping power requirement, and
consequently reduce the overall installation and maintenance costs.
Molten salts referring to salts which are heated to the liquid phase have been
regarded as promising TES materials. They have advantages such as low vapour
pressure, high operating temperature, and good thermal stability, which makes them
appealing for high-temperature sensible heat storage. However, the specific heat
capacity of a pure molten salt or salt mixture is often <2 kJ/kg °C, which is not ideal
to meet the industrial criteria for higher efficiency. In this sense, different
nanomaterials are introduced to molten salts to enhance their specific heat capacity
without impacting the melting temperature and thermal stability, taking advantages
of the temperature sensitive interactions between the molten salt and the additive.
2 Sensible Heat Storage Capacity
The energy released by a material as its temperature is reduced or absorbed by a
material as its temperature is increased, is called the sensible heat [1]. It should be
noted that sensible heat storage media undergo no changes in their phase over the
operating temperature range during the charging/discharging process.
Direct full/partial load supply
Charging process
D ischarging process
TES
Power
Block
Heat
Source
Solar DNI
Geothermal
Waste heat etc.
DSG
Fuels
Electricity etc.
Active storage
Passive storage
Latent heat
Sensible heat
Thermochemical
Fig. 1 A process sketch of heat source utilisation with the integration of TES (DNI: Direct Normal
Irradiance. DSG: Direct Steam Generation) [1–3]
Nanomaterials Enhanced Heat Storage in Molten Salts
industry [1]. High-temperature TES is especially suitable to be integrated into concentrating solar power (CSP) plants to solve the mismatch between energy supply
and demand. Since 2006, operators have built TES systems into CSP plants almost
exclusively using sensible heat for heat storage [2].
In the TES system, the design of the storage configuration depends on the scaled
capacity and storage media. Therefore, for a given scale of storage capacity, TES
media with higher heat capacity can reduce the amount of materials required,
resulting in smaller size of storage tanks and less pumping power requirement, and
consequently reduce the overall installation and maintenance costs.
Molten salts referring to salts which are heated to the liquid phase have been
regarded as promising TES materials. They have advantages such as low vapour
pressure, high operating temperature, and good thermal stability, which makes them
appealing for high-temperature sensible heat storage. However, the specific heat
capacity of a pure molten salt or salt mixture is often <2 kJ/kg °C, which is not ideal
to meet the industrial criteria for higher efficiency. In this sense, different
nanomaterials are introduced to molten salts to enhance their specific heat capacity
without impacting the melting temperature and thermal stability, taking advantages
of the temperature sensitive interactions between the molten salt and the additive.
2 Sensible Heat Storage Capacity
The energy released by a material as its temperature is reduced or absorbed by a
material as its temperature is increased, is called the sensible heat [1]. It should be
noted that sensible heat storage media undergo no changes in their phase over the
operating temperature range during the charging/discharging process.
Direct full/partial load supply
Charging process
D ischarging process
TES
Power
Block
Heat
Source
Solar DNI
Geothermal
Waste heat etc.
DSG
Fuels
Electricity etc.
Active storage
Passive storage
Latent heat
Sensible heat
Thermochemical
Fig. 1 A process sketch of heat source utilisation with the integration of TES (DNI: Direct Normal
Irradiance. DSG: Direct Steam Generation) [1–3]
Nanomaterials Enhanced Heat Storage in Molten Salts