  We calculate the colour averaged and colour singlet free energies of static
quark anti-quark sources placed in a thermal gluonic heat bath. We discuss the
renormalization of these free energies using the short distance properties of
the zero temperature heavy quark potential. This leads to the definition of the
renormalized Polyakov loop as an order parameter for the deconfinement phase
transition of the SU(3) gauge theory which is well behaved in the continuum
limit.
