  Spin caloritronics is the science and technology to control spin, charge, and
heat currents in magnetic nanostructures. The spin degree of freedom provides
new strategies for thermolelectric power generation that have not yet been
fully explored. After an elementary introduction into conventional
thermoelectrics and spintronics, we give a brief review of the physics of spin
caloritronics. We discuss spin-dependent thermoelectrics based on the the
two-current model in metallic magnets as well as the spin Seebeck and Peltier
effects that are based on spin wave excitations in ferromagnets. We derive
expressions for the efficiency and figure of merit ZT of several spin
caloritronic devices.
