Using Keldysh's non-equilibrium Green's function formalism within different decoupling schemes in the equation of motion (EOM), we have analyzed thermoelectric transport properties of a single quantum dot (QD) coupled to Bardeen-Cooper-Schrieffer (BCS) superconductor (S) and/or normal metal (N). At the infinite-U limit, we will first present the linear and non-linear thermoelectric transport properties of the N-QD-N particle exchange heat engine. The infinite-U results in Coulomb blockade and weak coupling regime show a good quantitative agreement with recent experiments. Next, we will briefly highlight our results for a hybrid QD system in which a BCS superconductor replaces the normal metallic drain reservoir. The results show that the N-QD-S system exhibits a finite Seebeck and Peltier cooling effect, thus making it a promising candidate for low-temperature thermal applications such as quantum dot-based power generators, refrigerators, quantum heat valves, and rectifiers.