Civil Engineering Reference
In-Depth Information
4.5 Sea Water Thermal Energy Storage
The sea water can act as an essential source for distributing the cooling energy to a
large-district cooling facility, wherein the low-temperature sea water is fed to a
series of chiller systems for producing the required cooling effect in buildings. The
chiller or the heat exchanger cools down the temperature of sea water to around
5-6 C, which is then pumped to the air-handling units to serve the cooling
demand in buildings. The warm return sea water coming from the building side at
a temperature of 12-15 C is then pumped back to the chiller plant, and the
process is repeated.
The volume flow rate of the sea water is maintained in such a way that the
desired quantity of sea water only would be supplied to the district cooling plant,
and the excess would be returned to the seabed. The issues of corrosion, salt
deposition and other scale formation are of main concern in utilizing this system,
but by providing proper corrosion-proof coatings, these challenges can be effec-
tively confronted. The cooling capacity of the district cooling plant can be achieved
in the order of 30-50 MW using the sea water cool thermal storage system.
4.6 Cavern Thermal Energy Storage
The cavern thermal storage is an attractive way of meeting the cooling/heating
load requirements in the small- to medium-scale building construction. The
schematic representation of the cavern TES system is illustrated in Fig.
7
. Basi-
cally, this system performs the storage and distribution of heat energy using the
underground water reservoirs on large landscape. There are two types of cavern
energy storage systems, namely the hot water storage and gravel water storage.
In the hot water storage, huge volumes of water are filled inside the insulated
cavity or the pit-like structure (tank) built underground, which in turn facilitate to
take advantage of the underground heat energy, i.e. cool and heat energy in
Fig. 7 Schematic
representation of the cavern
TES system
