  A model of a superconducting tunnel junction which refrigerates a nearby
metallic island without any particle exchange is presented. Heat extraction is
mediated by charge fluctuations in the coupling capacitance of the two systems.
The interplay of Coulomb interaction and the superconducting gap reduces the
power consumption of the refrigerator. The island is predicted to be cooled
from lattice temperatures of 200~mK down to close to 50~mK, for realistic
parameters. The results emphasize the role of non-equilibrium correlations in
bipartite mesoscopic conductors. This mechanism can be applied to create local
temperature gradients in tunnel junction arrays or explore the role of
interactions in the thermalization of non-equilibrium systems.
