  We calculate the gravitational self-energy of vacuum quantum field
fluctuations using a Casimir approach. We find that the Casimir gravitational
self-energy density can account for the measured dark energy density when the
SUSY-breaking energy is approximately 5 TeV, in good agreement with current
estimates. Furthermore, the Casimir gravitational self-energy appears to
provide a quantum mechanism for the well-know geometric relation between the
Planck, SUSY and cosmological constant energy scales.
