Correlation coefficient of the network has a close relationship with the network survivability. The study shows
that for non-similar hybrid network, removing a few high degree nodes of the network will make devastating
damage. Because those nodes widely distributed in the network forming many channels with other many other
nodes which is the important support for the network connectivity. Therefore, the invulnerability of FEIT is poor,
if the energy war, the energy crisis and other problems occur in those countries with high degree, it is likely to
spread to other countries, so that the global fossil energy trade will be affected.