equations are a coupled system of nonlinear partial differential
equations consisting of the Nernst-Planck equation and
the electrostatic Poisson equation with delta distribution sources,
which describe the electrodiffusion of ions in a solvated
biomolecular system. In this paper, some error bounds for a piecewise
finite element approximation to this problem are derived. Several numerical
examples including biomolecular problems are shown to support our analysis.