The levy was on account of disproportionate current usage
The Tamil Nadu Electricity Regulatory Commission (TNERC) has directed the Tamil Nadu Generation and Distribution Corporation (Tangedco) to refund the compensation charges levied on Indian Oil Corporation (IOC) for discharge of harmonics during the three months time granted for rectification.
Harmonics are generated by any load that draws current disproportionate to the voltage applied.
According to the petition, Tangedco had issued a notice on October 31, 2014 to IOC, granting a three-month period to bring down the harmonic limit within permissible limits. This was following an inspection in September that year. The notice said if there is a default, IOC would have to pay compensation charges at 15% of current consumption charges. Even when the measures to mitigate the harmonics was under process, Tangedco imposed a compensation charge of Rs. 17,35,877 with retrospective effect from October 2014 in the Current Consumption (CC) bills of March 2015, IOC said.
‘Charges not in order’
The state utility continued raising the compensation charges in the monthly bills of April 2015, May 2015, June 2015, July 2015 for Rs. 2,99,193, Rs. 2,97,174, Rs. 3,70,830 and Rs. 3,75,939 respectively, it added. Tangedco said discharge of harmonics severely affected its grid power quality and it was the responsibility of the company to reduce its harmful effects by maintaining within limits.
The TNERC said the levy charged retrospectively before the expiry of the three-month period granted to the consumer to rectify the limits of harmonics was not in order.
The compensation charges collected prior to the expiry date of the three-month period, i.e prior to 24.12.2014, is liable for refund, it said.
However, the TNERC said that IOC is liable to pay compensation charges for the period after the expiry date of the three-month notice on 23.12.2014 to the date of rectification of limits of harmonics, which is 28.11.2015.

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