A plasma reactor is provided, which includes a discharge chamber with dimensional characteristics and configuration of dielectric and electrodes so as to enhance efficiency based on the characteristics of the corona discharge streamers generated. Upon application of a pulsed high voltage potential, the discharge chamber enables formation of plasma where surface streamers play a greater role in the overall energy density of the discharge chamber than gas streamers. The formation of gas streamers is constrained. Because surface streamers have a higher energy density, the present invention is able to achieve improved energy efficiency while preserving effectiveness for gas treatment.