We examine the thermopower Q of a mesoscopic normal-metal (N) wire in contact with superconducting (S) segments and show that even with electron-hole symmetry Q may become finite due to the presence of supercurrents. Moreover, we show how the dominant part of Q can be directly related to the equilibrium supercurrents in the structure. In general, a finite thermopower appears both between the N reservoirs and the superconductors and between the N reservoirs themselves. The latter, however, strongly depends on the geometrical symmetry of the structure.