  We have studied the electrical conductivity of two-dimensional nanowire
networks. An analytical evaluation of the contribution of tunneling to their
electrical conductivity suggests that it is proportional to the square of the
wire concentration. Using computer simulation, three kinds of resistance were
taken into account, viz., (i) the resistance of the wires, (ii) the wire---wire
junction resistance, and (iii) the tunnel resistance between wires. We found
that the percolation threshold decreased due to tunneling. However, tunneling
had negligible effect on the electrical conductance of dense nanowire networks.
