  In N=1 supergravity the scalar potential may have supersymmetric (SUSY) and
non-supersymmetric Minkowski vacua (associated with supersymmetric and physical
phases) with vanishing energy density. In the supersymmetric Minkowski (second)
phase some breakdown of SUSY may be induced by non-perturbative effects in the
observable sector that give rise to a tiny positive vacuum energy density.
Postulating the exact degeneracy of the physical and second vacua as well as
assuming that at high energies the couplings in both phases are almost
identical, one can estimate the dark energy density in these vacua. It is
mostly determined by the SUSY breaking scale M_S in the physical phase.
Exploring the two-loop renormalization group (RG) flow of couplings in these
vacua we find that the measured value of the cosmological constant can be
reproduced if M_S varies from 20 TeV to 400 TeV. We also argue that this
prediction for the SUSY breaking scale is consistent with the upper bound on
M_S in the higgsino dark matter scenario.
