For Nigerians to enjoy stable power supply it is important to have an efficient, effective, and uninterrupted transmission system. The lack of this has been the bane of the current epileptic and unsustainable power supply the country is experiencing.
Nigeria is currently estimated to have between 10,000 to 15, 000 megawatts but unfortunately, it can only wheel just about 5,000 or maximum 7000 megawatts. This is because of the lack of investment in transmission equipment over the years which has resulted in the power industry relying on weak transmission lines and substations among others which have contributed to the bad electricity supply situation.
Various administrations over the years have paid leap services to the power sector, made budget provisions that were not made available to the management of the power sector. The sector, particularly the Transmission subsector was laid prostrate by the government’s inactions.
But realizing that this critical segment forms the nerve centre of the power sector, and also knowing that without a stable and steady transmission system the whole electricity eco–system will be a charade, the management of Transmission Company of Nigeria (TCN) decided to take some pragmatic steps that will eventually relief Nigerians of this harrowing experience they are going through because of lack of supply of electricity.
To address this issue head-on, the TCN is currently working on over 175 ongoing substations; transformer and transmission line projects which are at various completion stages nationwide. There are about 40 ongoing Greenfield substation and control room projects and about 45 new transformer projects and several transmission lines re-conductored or ongoing. TCN equally has almost 90 transformer-related projects across its ten regional offices. Some of the transformers have been completed while others are undergoing installation or reinforcement. On system collapse, can be caused by Generation, transmission or Distribution component of the power sector value chain. Grid stability is a result of efforts by stakeholders in the power sector.
On the part of TCN however, what has the company done? TCN has made several investments to strengthen the grid and this has enabled the Nigerian Grid Control System to be more responsive to preventing collapses.
The results of TCN’s efforts are showing hope and progress and this contributed enormously to a strengthened national grid. For the first time in a long time, TCN’s electrical grid did not experience a total collapse for 421 days. This achievement marks a major advance in the nation’s power infrastructure rebuilding efforts.
Key strategies implemented to prevent system breakdowns
- Configuration and Enforcement of Free Governor Control:
Key TCN operators visited power generating stations nationwide, to configure and activate Primary Reserve, aligning with the Grid code provisions. They established a monitoring and enforcement mechanism for compliance with generator unit governor control. This effort has led to most units in the grid operating under Free Governor Control compliance.
The Free Governor Mode of Operation (FGMO) automatically adjusts generation to compensate for changes in frequency, ensuring stable output. Turbine governors play a crucial role in this process, regulating rotational speed in response to load changes. As electricity demand is varying, the governor control maintains the output frequency to be within the statutory limit by adjusting the generator output. This therefore maintains the output frequency within statutory limits, by adjusting the generator output, contributing to grid stability and reliability while reducing transmission losses significantly.
b.Effective under Frequency Relay Scheme:
Under frequency works by monitoring the system frequency to see if it reaches a threshold below the operating frequency. If this occurs, the relay activates and can either automatically trip a circuit breaker or alert the network operator. This operate when the demand is more than output of generators at a threshold below the operating frequency.
Due to generation shortfall, the load demand is occasionally more than the output of the genera, thus result in decline of frequency below acceptable threshold. To address this decline frequency which can result in cascade tripping of generators on under frequency and eventually lead to system collapse, the TCN management implement a strategic deployment of under frequency relay scheme to operate in two critical stages of frequency to trip a specify load and restore the system frequency to acceptable value. The relays were carefully mapped and successfully deployed across TCN substations on a rotational basis.
The implementation of free governor control and under-frequency relay schemes enables the grid to be stable and reliable.
- Deployment of IoT/VPN for Enhanced Grid Visibility:
Grid visibility has been the fulcrum for Grid operation and management, as efforts are being made to rehabilitate the SCADA/EMS system the management of TCN inaugurated a task force of in-house Engineers that provided a stop-gap solution to the Grid visibility, the System Operators at National Control Centre can see over ninety percent (90%) of the Generating stations and Transmission substations with the corresponding line flows.
This well-considered choice has resulted in notable improvements in overseeing the power grid. By deploying IoT sensors and devices developed by the in-house TCN Engineers, the ability for real-time monitoring has been established, enabling operators to proactively identify potential issues before they escalate into disruptive incidents. This predictive capability has played a pivotal role in maintaining the grid’s stability. Moreover, continuous efforts are in progress to expand this visibility further by incorporating additional transmission stations through this IoT integration.
- Infrastructure Upgrades / N-1 CONTINGENCY:
The TCN management has successfully ringed the Grid by meeting up with N-1 CONTINGENCY, by implication the grid is no longer a radial network where tripping of individual lines may cause instability in the system. The Grid is now a loop system due to massive investment in construction and dualization of critical circuits/Lines.
Lots of transmission projects are ongoing across the country in line with TCNs transmission expansion plan. Several 330kV network loops and double circuit lines have been executed and this enhances redundancy and reliability. Some of the transmission lines loops include;
Benin – Osogbo – Lagos – Omotosho – Benin
Benin – Ajaokuta – Abuja – Shiroro – Jebba – Osogbo – Benin
Alaoji – Onitsha – New Haven – Ugwaji – Ikot Ekpene – Alaoji
Alaoji – Afam – Ikot Ekpene – Alaoji
- Benin – Ajaokuta – Abuja – Shiroro – Kaduna – Jos – Makurdi – Ugwaji – New Haven – Onitsha – Benin
Other transmission line loops along with double circuit lines, provide redundancies in the grid, enhancing its stability and reducing the risk of bulk power disruption. This strategic infrastructure development is crucial for ensuring a reliable power supply in Nigeria.
The proactive efforts of the TCN management have led to substantial investments aimed at a comprehensive upgrade and modernization of the transmission infrastructure. These strategic endeavors encompass a multifaceted approach, including the strategic commissioning of new transmission stations and the judicious installation of power transformers and compensating devices in areas where their impact is most needed.
This comprehensive modernization drive has been instrumental in reinforcing the resilience and dependability of the grid. The newly commissioned transmission stations have not only expanded the network’s reach but have also brought a heightened level of operational flexibility. The integration of power transformers has not only augmented the transmission capacity but has also led to improved efficiency, translating into smoother power flow and less susceptibility to bottlenecks. This reinforcement in the grid improved the wheeling capacity of Nigeria Transmission Network from 7.3GW in 2021 to 8.1GW in 2022.
Furthermore, the deployment of compensating devices in critical locations has effectively addressed power quality concerns, ensuring a consistent and stable supply. By minimizing voltage fluctuations and reactive power imbalances, these devices have played a pivotal role in mitigating the risk of voltage sags, flickers, and other disturbances that could potentially disrupt the grid’s performance.
- Enhanced Maintenance Regime:
Maintaining the integrity of the power infrastructure has remained a paramount focus, TCN made a series of concerted efforts, including regular inspections, prompt repairs, and the implementation of proactive preventive maintenance strategies.
Thorough and regular inspections cover all power assets to detect wear, vulnerabilities, or emerging issues. Even minor deviations from optimal functioning are identified, enabling swift corrective actions. The timely repair of faults, worn components, or malfunctions is crucial. This approach prevents minor issues from escalating and ensures the overall efficiency of the infrastructure.
TCN employs predictive and scheduled maintenance techniques to address potential sources of failure proactively. This prevents critical problems from developing and sustains the reliability of the power network.
Preventive maintenance measures further underscore this commitment to infrastructure sustainability. By employing a range of predictive and scheduled maintenance techniques, potential sources of failure are proactively addressed before they can manifest into critical problems.
- Proactive Staff Response:
A team of trained, experience and dedicated staff members has consistently showcased their unwavering commitment through their proactive responses during times of emergencies. The rapid and well-coordinated actions, executed by well-experienced operators, have proven instrumental in averting potential crises from spiraling out of control. This collective effort has not only safeguarded the overall stability of the grid but has also effectively minimized disruptions that could otherwise have had far-reaching consequences.
Furthermore, their seamless collaboration and clear communication have played a pivotal role in maintaining a smooth workflow even under high-pressure circumstances. This has not only ensured a rapid response but has also fostered a sense of trust and confidence within the team.
g.TCN/NESI Collaborative Efforts:
The TCN management, in close partnership with other stakeholders within the Nigerian Electricity Supply Industry (NESI), has cultivated a spirit of collaboration to effectively tackle challenges and execute cohesive strategies. Notably, initiatives such as Power Purchase Agreements (PPA), Service Level Agreements (SLA), Power Evacuation Agreements (PEA) and NESI situation room daily reports have been orchestrated through this joint effort.
The NESI Daily Situation Room Evaluations signify an active commitment to real-time monitoring and adjustment. By scrutinizing grid performance on a regular basis, issues are promptly identified and addressed, bolstering the overall reliability and effectiveness of the power ecosystem.
This collaborative approach has not only addressed existing challenges but has also ushered in a more resilient and robust power landscape.
While good progress in improving its Grid Control System and gaining si This collaborative approach has not only addressed existing challenges but has also ushered in a more resilient and robust power landscape.
While good progress in improving its Grid Control System and gaining significant grid stability has been made, TCN recognizes that excellence in this difficult field is a never-ending road. The pursuit of grid reliability and resilience is never completely accomplished since new challenges and opportunities emerge on a regular basis. TCN on its part is totally committed to this purpose and will continue to pursue innovative ways to completely eliminate the threat of system collapse.
h)several substations projects have been executed while existing ones have also been upgraded. So many more are ongoing.
How TCN Is Addressing The Issue of Ensuring Effective, Efficient and Stable Transmission System.
For Nigerians to enjoy stable power supply it is important to have an efficient, effective and uninterrupted transmission system. The lack of this has been the bane of the current epileptic and unsustainable power supply the country is experiencing.
Nigeria is currently estimated to have between 10,000 to 15, 000 megawatts but unfortunately, it can only wheel just about 5,000 or maximum 7000 megawatts. This is because of the lack of investment in transmission equipment over the years and this has led the power industry to rely on weak transmission lines and substations among others which have contributed to the bad electricity supply situation.
Various administrations over the years have paid leap services to the power sector, made budget provisions that were not made available to the management of the power sector. The sector, particularly the Transmission subsector was laid prostrate by the government’s inactions.
But realizing that this critical segment forms the nerve centre of the power sector, and also knowing that without a stable and steady transmission system the whole electricity system will be a charade, the management of Transmission Company of Nigeria (TCN) decided to take some pragmatic steps that will eventually relief Nigerians of this harrowing experience they are going through because of lack of supply of electricity.
To address this issue head-on, the TCN is currently working on over 175 ongoing substations; transformer and transmission line projects which are at various completion stages nationwide. There are about 40 ongoing Greenfield substation and control room projects and about 45 new transformer projects and several transmission lines re-conductored or ongoing. TCN equally has almost 90 transformer-related projects across its ten regional offices. Some of the transformers have been completed while others are undergoing installation or reinforcement. On system collapse, can be caused by Generation, transmission or Distribution component of the power sector value chain. Grid stability is a result of efforts by stakeholders in the power sector.
On the part of TCN however, what has the company done? TCN has made several investments to strengthen the grid and this has enabled the Nigerian Grid Control System to be more responsive to preventing collapses.
The results of TCN’s efforts are showing hope and progress and this contributed enormously to a strengthened national grid. For the first time in a long time, TCN’s electrical grid did not experience a total collapse for 421 days. This achievement marks a major advance in the nation’s power infrastructure rebuilding efforts.
Key strategies implemented to prevent system breakdowns
- Configuration and Enforcement of Free Governor Control:
Key TCN operators visited power generating stations nationwide, to configure and activate Primary Reserve, aligning with the Grid code provisions. They established a monitoring and enforcement mechanism for compliance with generator unit governor control. This effort has led to most units in the grid operating under Free Governor Control compliance.
The Free Governor Mode of Operation (FGMO) automatically adjusts generation to compensate for changes in frequency, ensuring stable output. Turbine governors play a crucial role in this process, regulating rotational speed in response to load changes. As electricity demand is varying, the governor control maintains the output frequency to be within the statutory limit by adjusting the generator output. This therefore maintains the output frequency within statutory limits, by adjusting the generator output, contributing to grid stability and reliability while reducing transmission losses significantly.
b.Effective under Frequency Relay Scheme:
Under frequency works by monitoring the system frequency to see if it reaches a threshold below the operating frequency. If this occurs, the relay activates and can either automatically trip a circuit breaker or alert the network operator. This operate when the demand is more than output of generators at a threshold below the operating frequency.
Due to generation shortfall, the load demand is occasionally more than the output of the genera, thus result in decline of frequency below acceptable threshold. To address this decline frequency which can result in cascade tripping of generators on under frequency and eventually lead to system collapse, the TCN management implement a strategic deployment of under frequency relay scheme to operate in two critical stages of frequency to trip a specify load and restore the system frequency to acceptable value. The relays were carefully mapped and successfully deployed across TCN substations on a rotational basis.
The implementation of free governor control and under-frequency relay schemes enables the grid to be stable and reliable.
- Deployment of IoT/VPN for Enhanced Grid Visibility:
Grid visibility has been the fulcrum for Grid operation and management, as efforts are being made to rehabilitate the SCADA/EMS system the management of TCN inaugurated a task force of in-house Engineers that provided a stop-gap solution to the Grid visibility, the System Operators at National Control Centre can see over ninety percent (90%) of the Generating stations and Transmission substations with the corresponding line flows.
This well-considered choice has resulted in notable improvements in overseeing the power grid. By deploying IoT sensors and devices developed by the in-house TCN Engineers, the ability for real-time monitoring has been established, enabling operators to proactively identify potential issues before they escalate into disruptive incidents. This predictive capability has played a pivotal role in maintaining the grid’s stability. Moreover, continuous efforts are in progress to expand this visibility further by incorporating additional transmission stations through this IoT integration.
- Infrastructure Upgrades / N-1 CONTINGENCY:
The TCN management has successfully ringed the Grid by meeting up with N-1 CONTINGENCY, by implication the grid is no longer a radial network where tripping of individual lines may cause instability in the system. The Grid is now a loop system due to massive investment in construction and dualization of critical circuits/Lines.
Lots of transmission projects are ongoing across the country in line with TCNs transmission expansion plan. Several 330kV network loops and double circuit lines have been executed and this enhances redundancy and reliability. Some of the transmission lines loops include;
Benin – Osogbo – Lagos – Omotosho – Benin
Benin – Ajaokuta – Abuja – Shiroro – Jebba – Osogbo – Benin
Alaoji – Onitsha – New Haven – Ugwaji – Ikot Ekpene – Alaoji
Alaoji – Afam – Ikot Ekpene – Alaoji
- Benin – Ajaokuta – Abuja – Shiroro – Kaduna – Jos – Makurdi – Ugwaji – New Haven – Onitsha – Benin
Other transmission line loops along with double circuit lines, provide redundancies in the grid, enhancing its stability and reducing the risk of bulk power disruption. This strategic infrastructure development is crucial for ensuring a reliable power supply in Nigeria.
The proactive efforts of the TCN management have led to substantial investments aimed at a comprehensive upgrade and modernization of the transmission infrastructure. These strategic endeavors encompass a multifaceted approach, including the strategic commissioning of new transmission stations and the judicious installation of power transformers and compensating devices in areas where their impact is most needed.
This comprehensive modernization drive has been instrumental in reinforcing the resilience and dependability of the grid. The newly commissioned transmission stations have not only expanded the network’s reach but have also brought a heightened level of operational flexibility. The integration of power transformers has not only augmented the transmission capacity but has also led to improved efficiency, translating into smoother power flow and less susceptibility to bottlenecks. This reinforcement in the grid improved the wheeling capacity of Nigeria Transmission Network from 7.3GW in 2021 to 8.1GW in 2022.
Furthermore, the deployment of compensating devices in critical locations has effectively addressed power quality concerns, ensuring a consistent and stable supply. By minimizing voltage fluctuations and reactive power imbalances, these devices have played a pivotal role in mitigating the risk of voltage sags, flickers, and other disturbances that could potentially disrupt the grid’s performance.
- Enhanced Maintenance Regime:
Maintaining the integrity of the power infrastructure has remained a paramount focus, TCN made a series of concerted efforts, including regular inspections, prompt repairs, and the implementation of proactive preventive maintenance strategies.
Thorough and regular inspections cover all power assets to detect wear, vulnerabilities, or emerging issues. Even minor deviations from optimal functioning are identified, enabling swift corrective actions. The timely repair of faults, worn components, or malfunctions is crucial. This approach prevents minor issues from escalating and ensures the overall efficiency of the infrastructure.
TCN employs predictive and scheduled maintenance techniques to address potential sources of failure proactively. This prevents critical problems from developing and sustains the reliability of the power network.
Preventive maintenance measures further underscore this commitment to infrastructure sustainability. By employing a range of predictive and scheduled maintenance techniques, potential sources of failure are proactively addressed before they can manifest into critical problems.
- Proactive Staff Response:
A team of trained, experience and dedicated staff members has consistently showcased their unwavering commitment through their proactive responses during times of emergencies. The rapid and well-coordinated actions, executed by well-experienced operators, have proven instrumental in averting potential crises from spiraling out of control. This collective effort has not only safeguarded the overall stability of the grid but has also effectively minimized disruptions that could otherwise have had far-reaching consequences.
Furthermore, their seamless collaboration and clear communication have played a pivotal role in maintaining a smooth workflow even under high-pressure circumstances. This has not only ensured a rapid response but has also fostered a sense of trust and confidence within the team.
g.TCN/NESI Collaborative Efforts:
The TCN management, in close partnership with other stakeholders within the Nigerian Electricity Supply Industry (NESI), has cultivated a spirit of collaboration to effectively tackle challenges and execute cohesive strategies. Notably, initiatives such as Power Purchase Agreements (PPA), Service Level Agreements (SLA), Power Evacuation Agreements (PEA) and NESI situation room daily reports have been orchestrated through this joint effort.
The NESI Daily Situation Room Evaluations signify an active commitment to real-time monitoring and adjustment. By scrutinizing grid performance on a regular basis, issues are promptly identified and addressed, bolstering the overall reliability and effectiveness of the power ecosystem.
This collaborative approach has not only addressed existing challenges but has also ushered in a more resilient and robust power landscape.
While good progress in improving its Grid Control System and gaining si This collaborative approach has not only addressed existing challenges but has also ushered in a more resilient and robust power landscape.
While good progress in improving its Grid Control System and gaining significant grid stability has been made, TCN recognizes that excellence in this difficult field is a never-ending road. The pursuit of grid reliability and resilience is never completely accomplished since new challenges and opportunities emerge on a regular basis. TCN on its part is totally committed to this purpose and will continue to pursue innovative ways to completely eliminate the threat of system collapse.
h)several substations projects have been executed while existing ones have also been upgraded. So many more are ongoing.
