  Despite its intrinsic non-equilibrium origin, thermoelectricity in nanoscale
systems is usually described within a static scattering approach which
disregards the dynamical interaction with the thermal baths that maintain
energy flow. Using the theory of open quantum systems we show instead that
unexpected properties, such as a resonant structure and large sign sensitivity,
emerge if the non-equilibrium nature of this problem is considered. Our
approach also allows us to define and study a local temperature, which shows
hot spots and oscillations along the system according to the coupling of the
latter to the electrodes. This demonstrates that Fourier's law -- a paradigm of
statistical mechanics -- is violated at the nanoscale.
