An electrically enhanced air filtration system is disclosed which uses rear fiber charging is disclosed. In particular, a fibrous filter may be placed in an upstream position within the system with one or more ionization arrays positioned downstream or to the rear of the fibrous filter in terms of airflow direction. The fibrous filter may include a grounded side and fiber side with the grounded side being upstream of the fiber side. The ionization array may include a plurality of electrodes each extending unidirectionally toward the fibrous filter.