  We analyze the heat current flowing across interacting quantum dots within
the Coulomb blockade regime. Power can be generated by either voltage or
temperature biases. In the former case, we find nonlinear contributions to the
Peltier effect that are dominated by conventional Joule heating for
sufficiently high voltages. In the latter case, the differential thermal
conductance shows maxima or minima depending on the energy level position.
Furthermore, we discuss departures from the Kelvin-Onsager reciprocity relation
beyond linear response.
