How does the Seebeck effect create a voltage in a thermoelectric generator?

The Seebeck effect creates a voltage in a thermoelectric generator by utilizing a temperature differential across a circuit composed of dissimilar conductive materials.12

In a typical thermoelectric power generator, this is achieved by connecting two legs of material—often p-type and n-type semiconductors—between a heat source and a heat sink. When the junctions are maintained at different temperatures, the temperature gradient ($\Delta T$) induces an electromotive force.31

The resulting voltage ($V_{\alpha }$) is determined by the relationship $V_{\alpha }=\alpha \Delta T$, where $\alpha$ represents the Seebeck coefficient of the materials used. This voltage drives an electric current through the circuit when an electrical load is connected. By maintaining this temperature difference, the device continuously converts thermal energy directly into electrical power without intermediate conversion processes.314