The power sector is undergoing major changes owing to the changing consumer load profile and expectations, greater integration of renewables, the growth of distributed generation and microgrids, the proliferation of electric vehicles and charging infrastructure, and theuptake of battery storage systems. The market is also changing, with the augmentation in network transfer capability, introduction of new products and an expected growth in cross-border trading. The grid needs to evolve alongside these changes without compromising on reliability and resilience. This will require greater automation, additional reserves and a robust communication backbone, among other things. At Power Line’s recent conference on “Power Transmission in India”, S.K. Soonee, adviser, Power System Operation Corporation Limited, shared his views on the changing sector dynamics, future grid requirements, and challenges and opportunities. Excerpts…
During the pandemic, the demand for electricity may have decreased, but its value is higher than ever before. The robust Indian transmission system facilitated the availability of reliable power across the country even under these challenging circumstances. The credit goes to those who built it, those who are maintaining and operating the grid with matching support from generation and other utilities. The power sector is on the cusp of change and, accordingly, grid operations are expected to undergo a transition.
Changing sector dynamics
The energy mix is changing rapidly as the share of fossil fuels is expected to decrease while that of renewable energy, particularly solar, is likely to increase.
The shape of the load curve is also changing. The days of having evening peaks are almost over. Now, a peak would either occur in the morning, when the maximum number of activities take place, or in late evening, when consumers need thermal comfort or air conditioning. The lighting load is also decreasing, firstly because of LEDs and secondly, because of consumer behavioural changes. The functioning of the power sector depends on consumer load and if the load changes, naturally, everything else has to also change. In this scenario, load forecasting has become crucial because the load is no longer following the historical patterns.
Changes have also been witnessed on the market side, where new products are being introduced. For instance, the real-time market was introduced last year. In case of ancillary services, regulated ancillary services are working very well, but we need a market at the tertiary reserves level. In the near future, financial derivatives are also expected to be launched, which would require significant capacity building and preparatory actions. In times to come, the market will become more nuanced and granular as newer niche products come in.
Net, net, there would be many changes, such as variations in net load, growing flexibility needs, and declining system inertia with renewable energy integration, but the need for a strong grid would prevail. Today, if India has an upper edge, it is because of its strong national grid. The country is now thinking of “one-sun-one-world-one-grid” (OSOWOG), which will entail more interconnections, but the strength of the grid must not be compromised.
“Load forecasting has become crucial because of the load not following historical patterns.”
First and foremost, our systems and processes need to change. This is a lesson from the Covid-19 crisis. There is a need to accelerate the application of robotics. Transcos can carry out several activities remotely, except physical tasks, which cannot be automated. We have already seen how IEC 61850 has helped reduce large control rooms to miniature terminals.
The distribution segment also needs toning up. There is a need to introduce the concept of distribution system operators (DSOs). However, establishing DSOs will take time, as it needs a strong policy framework. These DSOs would take care of the changes that are happening at the load side, such as an increasing fleet of electric vehicles and storage systems. Also, gradually, we will need greater interaction between DSOs and the independent system operators.
There is also a need for risk-based planning while keeping probabilistic scenarios in mind, strengthening cross-border links, and modernising load despatch centres.
The first job of load despatch centres is to ensure the reliability of the grid and the second is to enable economic despatch of power. For reliability, we need more controls and reserves. Automatic generation control is entering the regional and national levels in a big way, but similar steps have to be taken at the intra-state level. Every state must keep reserves. Further, flexibile resources are required at the state level. Security constrained economic despatch is operational for interstate generating stations. Similar initiatives are needed at the intra-state state level too.
The communication network and bandwidth available for power system operation needs to be augmented for seamless remote operations. The power sector must have its own cyber secure and strong communication backbone. Now that the Central Transmission Utility has started functioning, serious deliberations must take place regarding communication, backup communication, and closed user group communication in the sector.
Utilisation of the recently commissioned Renewable Energy Management Centres has to be ramped up. Another key area is data analytics and extracting insights out of the available data and information.
The national open access registry (NOAR), a digital platform for the pan-Indian electricity market, is going to be a big gamechanger in the sector. So far, we have only had fragmented software for market transactions and, therefore, the NOAR will be a key change in terms of IT infrastructure and layout. I hope the NOAR becomes operational this year.
“There is a need to accelerate the application of robotics.”
Challenges and opportunities
Since systems and processes are changing in the power sector, particularly post Covid, there are numerous opportunities for all stakeholders. Non-utility businesses, such as battery storage, are expected to grow well in the coming years. In addition, there are opportunities in the areas of cybersecurity, reliability and automation solutions. However, there are issues and challenges as well.
Since the value of electricity has increased tremendously, the value of lost load has also risen and therefore, the reliability and resilience of grids/networks have become extremely crucial. While grid economy is important, reliability and resilience should not be compromised. Further, with the fast evolution of technologies, the skillsets of the existing workforce will need enhancement. Capacity building initiatives will need to be taken up on a priority basis.
The physical grid currently follows the conventional “N-1” reliability criterion, which means that if one element trips, the grid will still remain secure. The criterion is well understood by policymakers, bureaucrats and regulators alike, but N-1 is not as simple as it sounds. It is a century-old concept. Now we need to work on criteria such as N-1-1, N-2 and N-G-1. The Mumbai outage in October 2020 has shown that if a generating element is out and at the same time, a transmission element also goes out, it becomes a critical contingency.
Going forward, there is need for a policy push for cross-border power trading and OSOWOG. Similarly, a greater push is required at the intra-state level. For grid reliability and resilience, more reserves need to be added to the system.They will come at a cost, but they are crucial nonetheless.