Section 8(4) in Tamil Nadu Electricity Grid Code, 2005
(4)Demarcation of responsibilities:(i)The SLDC shall have the total responsibility for:• [Scheduling or despatching the generation of all agencies including the Utilities, IPPs, Generators based on renewable sources of energy, Co-Generators, etc. connected to the Grid.] [Substituted by Noti. No. V1(21/207/2013. dated 12.09.2013.]• Regulating the demand of the beneficiaries / Distribution licensee in the State.• Regulating the drawal from the central generating stations and regulating the bilateral interchanges, if there is any.• Adopting merit order despatch, ABT procedures and free governor operation at power stations wherever possible.(ii)SLDC shall always endeavor to restrict its net drawal from central generating stations and other generating stations within their respective drawal schedules and the guidelines of ABT.(iii)The generating stations shall be responsible for power generation generally according to the daily schedule provided to them by the SLDC on the basis of the drawal schedules received from the beneficiaries / distribution licensee and also in accordance with Merit Order Despatch and Connectivity Agreements. However, the generating stations may deviate from the given schedules depending on the plant and system conditions with the prior approval from SLDC.Provided that when, the frequency is higher than 50.5 Hz, the actual net injection shall not exceed the scheduled despatch for that hour. Also while the frequency is above 50.5 Hz, the generating stations may (at their discretion) back down without waiting for the advice from SLDC. When the frequency falls below 49.5 Hz, the generation at all stations (except those on peaking duty) shall be maximized, at least up to the level, which can be sustained, without waiting for the advice from SLDC. Notwithstanding the above, the SLDC may direct the generating stations / beneficiaries to increase / decrease their generation/ drawal in case of contingencies e.g. overloading of lines / transformers, abnormal voltages, threat to system security. Such directions shall immediately be acted upon.(iv)For all outages of generation and transmission system, which may have an effect on the State Grid, all entities shall co-operate with each other and co-ordinate their actions as per the approved procedures separately. In particular, outages requiring restriction of generation which a beneficiary / distribution licensee can receive (and which may have a commercial implication) shall be planned carefully to achieve the best optimization. The entities shall furnish to the SLDC al81 requisite information for billing purposes.(v)All entities shall abide by the concept of frequency linked load despatch and pricing of deviations from schedule i.e. unscheduled interchanges. All generating units of the entities and the licensees shall normally be operated according to the standing frequency linked load despatch guidelines issued by the SLDC to the extent possible, unless otherwise advised by the SLDC.(vi)The STU shall opt to install special energy meters on all inter connections between the State entities and other identified points for recording of actual net MWh interchanges and MVArh drawals. The SLDC shall be responsible for computation of actual net MWh injection of each generating stations and actual net drawal of each beneficiary, 15 minute-wise, based on the above meter readings. The SLDC shall be responsible for Intra-State Energy Accounting as per the scheme approved by STU, and all entities shall extend the necessary assistance to the STU personnel in timely collection of metered data. The generators shall furnish the data as per Annexure D-2.(vii)The STU will undertake necessary Energy Audits in the Grid.
