It is shown that the ozone generation increases when a chopped DC positive voltage, frequency 2.5 kHz, is applied to a point-to-plane gap, compared with production obtained with a DC negative voltage. This method makes it possible to limit the thermal destruction effect and leads to a better repartition into the volume of the production by electron impact and photoionisation. It is thus possible to reach a concentration of 600 PPM with a yield of 125 PPM W-1 h-1.