3. Thermoelectric Effect
Thermoelectric technology is an alternative method of power
generation. The main building structure is the thermoelectric
module (TEM) that can directly convert heat to electricity. This
phenomenon was first observed by Seebeck [15]. The simple
concept is to apply temperature difference between two terminals
that trigger the generation of small amount of power (Fig. 3).
Alternatively, this thermoelectric module can function as a heat
pump according to Seebeck/Peltier effects. As shown in Fig. 3, two
electrical insulating ceramic plates enclose several p-type and ntype
thermo elements that are electrically connected in series and
thermally parallel with electrical insulation. As TEM is bi-functional
device which can either operate as Heating/Cooling device [16] or
generate power, this portability feature can well be exploited in
BIPV system for cooling PV module and simultaneously generating
extra power [17].
Thermoelectric module can be used as cooling system using
Peltier effect. The principle is to get a heat flux between the junction
of two thermo elements P and N. A Peltier cooler allow the
transfer of heat from one side of Peltier module to the other
depending on the current's direction [18]. We can also use the
Peltier cooler or thermoelectric cooler (TEC) as generator. If, we
want to use the thermoelectric as cooler, we apply a voltage across
the device and then we get that one side of the device is hot and the
other side is cold. The performance of TEC depends on ambient
temperature, design of the heat exchanger, Peltier parameters and
geometry of Peltier module.