The thermoelectric conversion offers unique possibility of a gigantic electric power generation utilizing low-temperature heat sources below 600K. Such sources are solar heat, terrestrial heat and exhaust waste heat from the central-station steam-electric plant. They are thermodynamically low grade but infinite and gratis. The immense production of electricity by this principle is made possible exclusively by means of the thermoelectric junction between the iron-based alloys as the conversion materials because these components of the generator can be manufactured on an efficient mass production basis.
Among several possible thermoelectric junctions basically consisted of iron, the Fe13%Al12%Si (p) -Fe12%Al (n) alloy couple has been found to exhibit a relatively high value of thermoelectric power, 71μV/K. The merit of this thermoelectric power junction with respect to the thermoelectric conversion has also been described by measuring other thermoelectric properties of these elements.