The quantification of harmonic emission requires an accurate representation of the network harmonic impedances. A number of techniques have been proposed to make the assessment of the network harmonic impedances practical and less invasive. Using actual event data, captured at a solar farm, this paper aims to utilize existing assessment techniques to develop an online network harmonic impedances assessment model. The harmonic impedances can then be updated per event and automatically be corrected as the network develops. This technique is noninvasive and will provide an accurate estimation of the network impedances enabling the continuous assessment of power quality emissions.