  Three different vortex glass models are studied by examining the energy
barrier against vortex motion across the system. In the two-dimensional gauge
glass this energy barrier is found to increase logarithmically with system size
which is interpreted as evidence for a low-temperature phase with zero
resistivity. Associated with the large energy barriers is a breaking of
ergodicity which explains why the well established results from equilibrium
studies could fail. The behavior of the more realistic random pinning model is
however different with decreasing energy barriers a no finite critical
temperature.
