Chennai: The Tamil Nadu Electricity Regulatory Commission has come out with separate draft regulations to enforce an intra-state availability based tariff (ABT) and forecasting, scheduling and deviation settlement mechanism for the wind and solar generators here paving the way for efficient management of load within the State by the distribution company.
The Commission, in its draft, said the narrowing down of frequency bandwidth by Central Electricity Regulatory Commission to 49.9 to 50.05 Hertz and the issue of deviation settlement mechanism regulations and its subsequent amendments with impetus on forecasting and scheduling of wind and solar generation, necessitates implementation of ABT in the state to enhance grid discipline. The commission has invited comments from the stakeholders before February 13.
The ABT is a three part tariff comprising of capacity charges, variable charges and deviation charges, the capacity charges being linked to availability, variable charge to scheduled energy and deviation charges at the rate applicable to the deviations from the scheduled.
The ABT is a performance-based tariff for supply of electricity and a new system of scheduling and dispatch that requires both generators and beneficiaries to “commit to day-ahead schedules”.
It is also a system of rewards and penalties to enforce pre-committed schedules, though variations are allowed, if notified early.
One of the main reasons for implementing ABT is to encourage grid discipline by making pricing of power frequency-dependent thereby forcing state participants to improve procedures for forecasting, scheduling and load despatch.
The other objectives are promotion of trade in energy and capacity, economic load despatch and encouragement of higher availability, the commission said.
The commission, in its draft on forecasting, scheduling, DSM and related matters of solar and wind generation sources, said that the objective of these regulations is to facilitate large scale grid integration of wind and solar generating stations.
while maintaining grid stability and security as envisaged under the grid code, through forecasting, scheduling and commercial mechanism for deviation settlement of these generators.
The CERC has issued framework regulations specifying settlement rates varying from Rs 0.50 per unit to Rs1.50 per unit for deviations caused by the wind and solar generators.
