The conductivity of large percolation network samples

A new method for calculating the conductivity of large finite random resistor lattices is described. The maximum resistor-lattice sample size and the time efficiency increases when the percolation threshold is approached. The method is applied to bond percolation on the square lattice where the conductivity exponent is found to be t=1.31+or-0.04, in agreement with recent results from renormalisation group treatments.