Field Determinations of HVDC Ozone Production Rates

The environment near a high voltage direct current (HVdc) transmission line experiences corona effects, including the production of oxidants. Field determination of ozone production rates were made at the Bonneville Power Administration (BPA) HVdc Test Facility, The Dalles, Oregon, in fall and winter 1977. A novel micrometeorological profiling technique was used to identify sources of ozone plumes. The results indicate that even during precipitation the atmospheric ozone concentrations from HVdc lines at voltages up to ±550 kV are relatively small. Measured atmospheric ozone concentration plumes are consistent with laboratory data predictions of ozone concentrations based on corona, line parameters, and ambient dispersion. This confirmation under worst-case field conditions demonstrates the validity of previous estimates of a very low magnitude of the potential ozone effects.