A commercial cooking equipment exhaust system, comprising: at least one filter unit (26, 28) positioned along an exhaust flow path; at least one electrostatic precipitator unit positioned downstream of the filter unit (26, 28) along the exhaust flow path and through which exhaust gases are moved during exhaust operations, the electrostatic precipitator including an ionizing section upstream of a collecting section, wherein the ionizing section comprises a plurality of ionizing wires and a plurality of ground plates (68A, 68B), said ground plates (68A, 68B) defining a plurality of ionizing flow paths through the ionizing section, each ionizing flow path having a side profile pattern, characterizing in that the side profile pattern of each ionizing flow path varies in width between at least one wide section and at least one narrow section, wherein the ionizing wires are located in wide sections and not in narrow sections, wherein the collecting section comprises a plurality of collecting plates, said collecting plates defining a plurality of collecting flow paths through the collecting section, each collecting flow path having a side profile pattern, wherein the side profile pattern of each collecting flow path has a substantially uniform width and a repeating undulating side profile pattern, and wherein the plurality of ionizing wires include multiple first ionizing wires and multiple second ionizing wires, the first ionizing wires lying in a first common plane perpendicular to a flow direction through the electrostatic precipitator, and the second ionizing wires lying in a second common plane perpendicular to the flow direction. at least one filter unit (26, 28) positioned along an exhaust flow path; at least one electrostatic precipitator unit positioned downstream of the filter unit (26, 28) along the exhaust flow path and through which exhaust gases are moved during exhaust operations, the electrostatic precipitator including an ionizing section upstream of a collecting section, wherein the ionizing section comprises a plurality of ionizing wires and a plurality of ground plates (68A, 68B), said ground plates (68A, 68B) defining a plurality of ionizing flow paths through the ionizing section, each ionizing flow path having a side profile pattern, characterizing in that the side profile pattern of each ionizing flow path varies in width between at least one wide section and at least one narrow section, wherein the ionizing wires are located in wide sections and not in narrow sections, wherein the collecting section comprises a plurality of collecting plates, said collecting plates defining a plurality of collecting flow paths through the collecting section, each collecting flow path having a side profile pattern, wherein the side profile pattern of each collecting flow path has a substantially uniform width and a repeating undulating side profile pattern, and wherein the plurality of ionizing wires include multiple first ionizing wires and multiple second ionizing wires, the first ionizing wires lying in a first common plane perpendicular to a flow direction through the electrostatic precipitator, and the second ionizing wires lying in a second common plane perpendicular to the flow direction.