  We propose an efficient method to compute the vacuum polarization energy of
static field configurations that do not allow a decomposition into symmetric
and anti-symmetric channels in one space dimension. In particular we compute
the vacuum polarization energy of the kink soliton in the $\phi^6$ model. We
link the dependence of this energy on the position of the center of the soliton
to the different masses of the quantum fluctuations at negative and positive
spatial infinity.
