Performance of a wire-plate electrostatic precipitator in the removal of particles with a wide particle size distribution was evaluated. The experimental rig utilized consisted of a set of three precipitators whose dimensions could be varied. It was observed that precipitator performance increased with an increase in the gap between the collecting plates, which resulted in a substantial increase in energy consumption per volume of cleaned gas. The grade efficiency predicted by correlations from the literature did not match the experimental measurements, and a new correlation is proposed.