Tariff Regulations
Tamil Nadu
The Tamil Nadu Electricity Regulatory Commission has issued the Terms and Conditions for Determination of Tariff for Intra state Transmission / Distribution of Electricity under Tariff Framework regulations dated 11th February 2009. The primary purpose of these regulations is to determine the tariff in all cases covered under these Regulations.
Tamil Nadu Electricity Grid Code, 2005
Resolution By
TNERC
Notification No. and date
TNERC/GC/13/1 Dated 19.10.2005
Objectives
1. To define the services rendered by each wing in the overall electric system and also for identifying the responsibility and performance factor and measurement points for each one of them.
2. To facilitates intra state transmission and wheeling of electricity, with a focus on the operation, maintenance, development and planning of the Tamil Nadu State Electricity Grid.
3. To bring out a single set of technical requirements encompassing all the Generators, Licensees, and State Transmission Utility connected to or related to or using the Intra State Transmission System and provides the following:
3.1. The documentation of the principles and procedures, which define the relationship between various users of the Intra State Transmission System and State Load Despatch Centre as well.
3.2. Responsibilities and obligation with respect to the operation of the State Transmission System (STS)
3.3. Suitable measures for connectivity with the Grid for all generating plants
3.4. The standards with reference to quality, continuity and reliability of service for compliance by the Licensees.
3.5. Planning of the State Electricity Grid and making arrangements for its operation, maintenance, development and expansion.
3.6. Operation of Grid under normal, abnormal and emergency conditions.
3.7. Procedures for black start, fast restart, restoration of supply after major disturbances.
3.8. Penalty for the non-compliance of this Grid Code, Grid Standards and the lawful directions of RLDC and SLDC.
3.9. Facilitation for beneficial trading of electricity by defining a common basis of operation of the Intra State Transmission System applicable to all the users of the system.
3.10. To ensure economy and efficiency in the operation of the power system in the State
3.11. To achieve compliance with the Grid Standards and other relevant Standards, Codes, Regulations and direction of SLDC by every licensee and others involved in the operation of the power system.
2. To facilitates intra state transmission and wheeling of electricity, with a focus on the operation, maintenance, development and planning of the Tamil Nadu State Electricity Grid.
3. To bring out a single set of technical requirements encompassing all the Generators, Licensees, and State Transmission Utility connected to or related to or using the Intra State Transmission System and provides the following:
3.1. The documentation of the principles and procedures, which define the relationship between various users of the Intra State Transmission System and State Load Despatch Centre as well.
3.2. Responsibilities and obligation with respect to the operation of the State Transmission System (STS)
3.3. Suitable measures for connectivity with the Grid for all generating plants
3.4. The standards with reference to quality, continuity and reliability of service for compliance by the Licensees.
3.5. Planning of the State Electricity Grid and making arrangements for its operation, maintenance, development and expansion.
3.6. Operation of Grid under normal, abnormal and emergency conditions.
3.7. Procedures for black start, fast restart, restoration of supply after major disturbances.
3.8. Penalty for the non-compliance of this Grid Code, Grid Standards and the lawful directions of RLDC and SLDC.
3.9. Facilitation for beneficial trading of electricity by defining a common basis of operation of the Intra State Transmission System applicable to all the users of the system.
3.10. To ensure economy and efficiency in the operation of the power system in the State
3.11. To achieve compliance with the Grid Standards and other relevant Standards, Codes, Regulations and direction of SLDC by every licensee and others involved in the operation of the power system.
Regulations called as
Tamil Nadu Electricity Grid Code
Planning Code for Intra-state Transmission- Introduction
1. The System Planning specifies the policy and procedures to be applied in planning of Tamil Nadu State Grid.
2. A requirement for reinforcement or extension of the State Transmission System may arise for a number of reasons such as:
2.1. Development on a User's system already connected to the State Transmission System.
2.2. Iintroduction of a new Connection point between the User's system and the State transmission System.
2.3. Evacuation system for Generating Stations within or outside the State.
2.4. A general increase in system capacity (due to addition of generation or system load) to remove operating constraints and maintain standards of security.
[Chapter 5 Clause no. 1]
2. A requirement for reinforcement or extension of the State Transmission System may arise for a number of reasons such as:
2.1. Development on a User's system already connected to the State Transmission System.
2.2. Iintroduction of a new Connection point between the User's system and the State transmission System.
2.3. Evacuation system for Generating Stations within or outside the State.
2.4. A general increase in system capacity (due to addition of generation or system load) to remove operating constraints and maintain standards of security.
[Chapter 5 Clause no. 1]
Planning Code for Intra-state Transmission- Objective
1. To define the procedure for the exchange of information between STU and a User in respect of any proposed development on the User’s system, which may have an impact on the performance of the User.
2. To detail out the information which STU shall make available to Users in order to facilitate the identification and evaluation of opportunities for use of or connection to State Transmission System.
3. To detail out the information required by STU from Users to enable STU to plan the development of its Transmission System to facilitate proposed User developments
4. To specify the planning and design standards, which will be applied by STU in planning and development of the power system.
[Chapter 5 Clause no. 2]
2. To detail out the information which STU shall make available to Users in order to facilitate the identification and evaluation of opportunities for use of or connection to State Transmission System.
3. To detail out the information required by STU from Users to enable STU to plan the development of its Transmission System to facilitate proposed User developments
4. To specify the planning and design standards, which will be applied by STU in planning and development of the power system.
[Chapter 5 Clause no. 2]
Planning Code for Intra-state Transmission- Planning Philosophy
1. STU would develop a perspective transmission plan for next 10 years for State Transmission System.
2. These perspective transmission plans would be updated every year to take care of the revisions in load projections and generation capacity additions.
3. The perspective plans shall be submitted to Commission for approval.
4. STU shall carry out annual planning process corresponding to a 5-year forward term for identification of major State Transmission System.
5. Both the long term and short term plans shall fit into National Electricity Plan formulated by Central Government, perspective plan developed by CEA, Electric Power Survey of India published by the CEA
6.Long term / short term plans prepared by Central Transmission Utility
[Chapter 5 Clause no. 3]
2. These perspective transmission plans would be updated every year to take care of the revisions in load projections and generation capacity additions.
3. The perspective plans shall be submitted to Commission for approval.
4. STU shall carry out annual planning process corresponding to a 5-year forward term for identification of major State Transmission System.
5. Both the long term and short term plans shall fit into National Electricity Plan formulated by Central Government, perspective plan developed by CEA, Electric Power Survey of India published by the CEA
6.Long term / short term plans prepared by Central Transmission Utility
[Chapter 5 Clause no. 3]
Planning Code for Intra-state Transmission- Criterion
1. The planning criterion are based on the security philosophy on which the STS has been planned.
2.The security philosophy may be as per the Transmission Planning Criteria and other guidelines as given by CEA.
The general planning criteria are detailed below:
2.1. As a general rule, the STS shall be capable of withstanding and be secured against the following contingency outages without necessitating load shedding or rescheduling of generation during Steady State Operation:
- Outage of a 110 kV D/C line or,
- Outage of a 230 kV D/C line or,
- Outage of a 400 kV S/C line or,
- Outage of single Interconnecting Transformer.
2.2. All the Generating Units may operate within their reactive capability curves and the network voltage profile shall also be maintained within voltage limits specified.
3. The STS shall be capable of withstanding the loss of most severe single system infeed without loss of stability.
[Chapter 5 Clause no. 7]
2.The security philosophy may be as per the Transmission Planning Criteria and other guidelines as given by CEA.
The general planning criteria are detailed below:
2.1. As a general rule, the STS shall be capable of withstanding and be secured against the following contingency outages without necessitating load shedding or rescheduling of generation during Steady State Operation:
- Outage of a 110 kV D/C line or,
- Outage of a 230 kV D/C line or,
- Outage of a 400 kV S/C line or,
- Outage of single Interconnecting Transformer.
2.2. All the Generating Units may operate within their reactive capability curves and the network voltage profile shall also be maintained within voltage limits specified.
3. The STS shall be capable of withstanding the loss of most severe single system infeed without loss of stability.
[Chapter 5 Clause no. 7]
Planning Code for Intra-state Transmission- Planning Data
For System Planning ISGS/State Generating companies/IPPs/ licensees has to supply two types of data.
1. Standard planning data
Standard planning data consists of details, which are expected to be normally sufficient for the STU to investigate the impact on the STS due to User development.
2. Detailed planning data
Detailed planning data consist of additional, more detailed data not normally expected to be required by STU to assess the impact of User development on the STS. This data shall be furnished by the Users of STS as and when requested by STU.
[Chapter 5 Clause no. 11]
1. Standard planning data
Standard planning data consists of details, which are expected to be normally sufficient for the STU to investigate the impact on the STS due to User development.
2. Detailed planning data
Detailed planning data consist of additional, more detailed data not normally expected to be required by STU to assess the impact of User development on the STS. This data shall be furnished by the Users of STS as and when requested by STU.
[Chapter 5 Clause no. 11]
Planning Code for Intra-state Transmission- Implementation of Transmission Plan
1. The actual program of implementation of transmission lines, Interconnecting Transformers, actors/capacitors and other transmission elements will be determined by STU in consultation with the concerned agencies.
2. The completion of these works, in the required time frame, shall be ensured by STU through the concerned agency.
[Chapter 5 Clause no. 12]
2. The completion of these works, in the required time frame, shall be ensured by STU through the concerned agency.
[Chapter 5 Clause no. 12]
Connection Code/ Grid connectivity- Objective
1. To ensure the basic rules for connections are complied with to treat all agencies in a nondiscriminatory manner
2. To ensure that any new or modified connections, when established, shall neither suffer unacceptable effects due to its connection to the transmission system nor impose unacceptable effects on the system of any other connected agency
3. To ensure that the ownership and responsibility for all the equipments, shall be clearly specified in a schedule (Site Responsibility Schedule)
4. To ensure that a prospective user is well informed, in advance, of the standards and conditions that his system has to meet, for being integrated into the existing power system
[Chapter 6 Clause no. 1]
2. To ensure that any new or modified connections, when established, shall neither suffer unacceptable effects due to its connection to the transmission system nor impose unacceptable effects on the system of any other connected agency
3. To ensure that the ownership and responsibility for all the equipments, shall be clearly specified in a schedule (Site Responsibility Schedule)
4. To ensure that a prospective user is well informed, in advance, of the standards and conditions that his system has to meet, for being integrated into the existing power system
[Chapter 6 Clause no. 1]
Connection Code/ Grid connectivity- Scope
The connectivity conditions apply to all State / Central Government sponsored generating companies, captive power generators, IPPs, STU, transmission / distribution Licensees, Bulk Consumers and all the users seeking new connection with the intra state transmission system including the existing
transmission licensees and the users who may be required to modify / upgrade their systems.
[Chapter 6 Clause no. 2]
transmission licensees and the users who may be required to modify / upgrade their systems.
[Chapter 6 Clause no. 2]
Connection Code/ Grid connectivity- Procedure for connection
1. STU shall identify opportunities for new connections and optimal locations after conducting the system studies.
2. STU shall furnish details of the prospective connection points in respect of their system on their web-site inviting initial application from the users.
3. The prospective users shall be required to pay to the STU/transmission licensee the charges as (proposed by STU/transmission licensee) approved by the Commission.
4. On receipt of the request from the user & transmission licensee along with the prescribed charges, the STU / transmission licensee shall, within one month of receipt of the proposal, accept the proposal or suggest modifications
5.The STU/ transmission licensee and the user/ transmission licensee shall enter into a Connection Agreement within two months of acceptance of the proposal.
6. The Connection Agreement shall contain time schedule for completion of the facilities of User and STU/ transmission licensee
7. Copies of the Connection Agreement shall be sent to the transmission licensee, load dispatch centre, Regional Power Committee, Commission and the Authority.
8. Upon fulfillment of all the conditions, STU shall notify the agency that it can be connected to the STS.
9. In respect of existing connections, the Commission may allow relaxation up to 2 years in respect of connection agreements. The process of renegotiation of the connection conditions of the STS should be completed within the above period.
[Chapter 6 Clause no. 3]
2. STU shall furnish details of the prospective connection points in respect of their system on their web-site inviting initial application from the users.
3. The prospective users shall be required to pay to the STU/transmission licensee the charges as (proposed by STU/transmission licensee) approved by the Commission.
4. On receipt of the request from the user & transmission licensee along with the prescribed charges, the STU / transmission licensee shall, within one month of receipt of the proposal, accept the proposal or suggest modifications
5.The STU/ transmission licensee and the user/ transmission licensee shall enter into a Connection Agreement within two months of acceptance of the proposal.
6. The Connection Agreement shall contain time schedule for completion of the facilities of User and STU/ transmission licensee
7. Copies of the Connection Agreement shall be sent to the transmission licensee, load dispatch centre, Regional Power Committee, Commission and the Authority.
8. Upon fulfillment of all the conditions, STU shall notify the agency that it can be connected to the STS.
9. In respect of existing connections, the Commission may allow relaxation up to 2 years in respect of connection agreements. The process of renegotiation of the connection conditions of the STS should be completed within the above period.
[Chapter 6 Clause no. 3]
Connection Code/ Grid connectivity- Connection Agreement
1. Every connection of a user’s system to the transmission system shall be covered by a Connection Agreement between the user and the transmission licensee.
2. The Connection Agreement shall contain general, specific, technical and financial conditions, applicable to that connection.
3. A connection agreement shall include the following (but not limited), within its terms and conditions, :
3.1. A condition requiring both parties to comply with Indian Electricity Grid Code and Tamil Nadu Electricity Grid code, provisions under the Act, other Codes and regulations issued by the commission / CEA.
3.2. Details of connections, technical requirements and commercial arrangements.
3.3. Details of capital expenditure if any required to be met before extending open access to the open access consumer
3.4. Site responsibility schedule
3.5. Details of the protection arrangements made and its coordination with the Grid.
3.6. Procedure necessary for site access, site operational activities and maintenance standards for STU equipment at the premises of the users and vice versa.
3.7 Specific clause to the effect that necessary guidelines for insulation coordination in live working shall be followed by the STU / Agency.
3.8. Commitment to provide the data requirements as per Annexure B-1 of the grid code.
[Chapter 6 Clause no. 5]
2. The Connection Agreement shall contain general, specific, technical and financial conditions, applicable to that connection.
3. A connection agreement shall include the following (but not limited), within its terms and conditions, :
3.1. A condition requiring both parties to comply with Indian Electricity Grid Code and Tamil Nadu Electricity Grid code, provisions under the Act, other Codes and regulations issued by the commission / CEA.
3.2. Details of connections, technical requirements and commercial arrangements.
3.3. Details of capital expenditure if any required to be met before extending open access to the open access consumer
3.4. Site responsibility schedule
3.5. Details of the protection arrangements made and its coordination with the Grid.
3.6. Procedure necessary for site access, site operational activities and maintenance standards for STU equipment at the premises of the users and vice versa.
3.7 Specific clause to the effect that necessary guidelines for insulation coordination in live working shall be followed by the STU / Agency.
3.8. Commitment to provide the data requirements as per Annexure B-1 of the grid code.
[Chapter 6 Clause no. 5]
Connection Code/ Grid connectivity- Important technical requirements for connectivity to the grid
1. Generating Stations including IPPs:
1.1.Generating stations Switchyard Voltage may be at the level of 400, 230 and 110 kV or as agreed to by the STU.
1.2. All the terminal, communication, protection and metering equipments owned by the generating agency, within the perimeter of their site shall be maintained by them.
1.3 From the outgoing feeder gantry onwards, all electrical equipments shall be maintained by the STU.
2. Distribution Licensee
2.1.The Voltage may be at the level of 110, 33, 22 and 11 kV.
2.2. The connection point shall be the outgoing feeder gantry of the STU’s sub-station, if the sub station is owned by STU, else, the connection point shall be the terminal structure feeder gantry at the entry into the sub station.
3. Inter-State transmission System
3.3. For the Southern Regional Transmission System, the inter state transmission link to the intra state system, the connection point, protection scheme, metering scheme, metering point and the voltage shall be in accordance with the mutual agreement between CTU and the STU.
4. Captive Generators, Co-generators and HV consumers
4.1. The voltage level may be at 230, 110, 66, 33, 22, 11 kV or as agreed to by STU.
4.2. Sub-stations shall be owned by Co-Generators, CPPs and the HV consumers.
4.3. The connection point shall be the feeder gantry on their premises.
[Chapter 6 Clause no. 7]
1.1.Generating stations Switchyard Voltage may be at the level of 400, 230 and 110 kV or as agreed to by the STU.
1.2. All the terminal, communication, protection and metering equipments owned by the generating agency, within the perimeter of their site shall be maintained by them.
1.3 From the outgoing feeder gantry onwards, all electrical equipments shall be maintained by the STU.
2. Distribution Licensee
2.1.The Voltage may be at the level of 110, 33, 22 and 11 kV.
2.2. The connection point shall be the outgoing feeder gantry of the STU’s sub-station, if the sub station is owned by STU, else, the connection point shall be the terminal structure feeder gantry at the entry into the sub station.
3. Inter-State transmission System
3.3. For the Southern Regional Transmission System, the inter state transmission link to the intra state system, the connection point, protection scheme, metering scheme, metering point and the voltage shall be in accordance with the mutual agreement between CTU and the STU.
4. Captive Generators, Co-generators and HV consumers
4.1. The voltage level may be at 230, 110, 66, 33, 22, 11 kV or as agreed to by STU.
4.2. Sub-stations shall be owned by Co-Generators, CPPs and the HV consumers.
4.3. The connection point shall be the feeder gantry on their premises.
[Chapter 6 Clause no. 7]
Corrigendum/ Amendment, if any
Yes, but not related to above parameter
Tamil Nadu Electricity Grid Code -2005 (1st Amendment)
Resolution By
TNERC
Notification No. and date
TNERC/GC/ 13-2, dated 12-09-2013
Corrigendum/ Amendment, if any
Changes made in
a.Scheduling and Despatch-
b.Demarcation of responsibilities
a.Scheduling and Despatch-
b.Demarcation of responsibilities