Detailed List of Action Items for the IBR Roadmap Document

Based on the conversation, the team's objectives, and the provided chapter structure, here is a comprehensive list of action items with specific changes and details to guide the completion and enhancement of the Inverter-Based Resources (IBR) roadmap document:

---

### 1. Clean Up the Current Draft Document

- Action: Revise and streamline the existing draft to create a clean, reviewable document.
- Details:
- Formatting: Ensure consistent formatting throughout the document according to organizational standards.
- Redundancy Removal: Eliminate any repetitive content or redundant sections.
- Logical Flow: Verify that the chapters are organized logically, enhancing the readability and coherence of the document.
- Template Update: Apply any updated LaTeX templates or stylesheets as required.

### 2. Complete and Integrate Chapter 3: International Approaches to IBR Integration

- Action: Finalize the content of Chapter 3 and integrate it into the main document.
- Details:
- Content Completion: Finish any pending sections or case studies within this chapter.
- Integration: Paste the completed content into the main LaTeX document to maintain consistency.
- Alignment: Ensure that the international examples presented are relevant and provide valuable insights for India's context.

### 3. Enhance Chapters 4 and 5 with Detailed Activities

#### Chapter 4: Technical Challenges and Solutions
- Action: Elaborate on the technical activities, adding specificity and practical details.
- Details:
- Elaboration: For each technical challenge, provide a detailed explanation of the solution strategies.
- Target Word Count: Aim for 50–75 words per activity, resulting in 2–3 informative sentences.
- Specificity: Include details such as required IBR model improvements, protection schemes, and stability analyses.
- Examples:
- Modeling Improvements: Describe the specific types of IBR models that need enhancement, such as detailed electromagnetic transient models or positive sequence models.
- Stability Assessments: Explain the methodologies for conducting comprehensive stability studies, including small-signal and large-disturbance analysis.

#### Chapter 5: Institutional Challenges and Solutions
- Action: Expand on the institutional activities by providing concrete steps and recommendations.
- Details:
- Policy Recommendations: Offer detailed suggestions for policy adjustments or developments needed to support IBR integration.
- Training Programs: Outline specific training initiatives for grid operators and planners.
- Inter-Institutional Collaboration: Highlight opportunities for collaboration between Grid India and other organizations (e.g., regulatory bodies, research institutions).

### 4. Reassess and Potentially Rebrand Chapters 6 and 7

- Action: Evaluate Chapters 6 and 7 to determine if they should be consolidated, rebranded, or modified.
- Details:
- Chapter 6: Prioritization of Key Challenges and Activities
- Option A: Integrate the prioritization directly into Chapters 4 and 5 by indicating the short, medium, and long-term relevance of each activity.
- Option B: Retain Chapter 6 but enhance it by summarizing key activities with their prioritization and responsible parties.
- Chapter 7: Roadmap Summary
- Expansion: Use this chapter to provide a comprehensive summary of all activities, serving as a quick reference for stakeholders.
- Visual Aids: Consider including tables or charts that consolidate this information if time allows.

### 5. Develop a Comprehensive Summary of Activities

- Action: Create an aggregated summary of all activities across technical and institutional domains.
- Details:
- Table Creation: Develop tables categorizing activities by domain (technical or institutional), priority level (short, medium, long term), and responsible parties.
- Content Alignment: Ensure that the activities in the summary reflect those detailed in Chapters 4 and 5.
- Justification: Provide brief explanations for the prioritization of each activity.

### 6. Remove Copywritten Figures and Consider Original Graphics

- Action: Eliminate any figures copied from other reports to avoid legal issues and decide on the inclusion of original graphics.
- Details:
- Immediate Removal: Delete any existing copyrighted figures from the document.
- Assessment: Evaluate whether original graphics would significantly enhance understanding.
- Time Constraints: Consider the tight timeline; only include graphics that can be developed quickly.
- Alternative Descriptions: Use descriptive text to convey information where graphics cannot be included.

### 7. Align Content with Grid India's Immediate Needs

- Action: Tailor the document to support Grid India's specific objectives and requirements.
- Details:
- Relevance: Ensure that all recommendations are directly applicable to Grid India's context.
- Proposals Support: Include content that can aid Grid India in developing proposals to bodies like the Central Electricity Authority (CEA).
- Emphasis: Focus on activities that Grid India can implement in the short term or require immediate attention.

### 8. Coordinate Internal and External Reviews

- Action: Plan and facilitate reviews with internal team members and external stakeholders.
- Details:
- Internal Reviewers: Share the draft with team members such as Adarsh for internal feedback.
- Timeline: Ensure internal reviews happen concurrently with external reviews to expedite the process.
- External Stakeholders: Coordinate with Manali to distribute the draft to Grid India and facilitate their feedback.
- Manali's Role: Leverage Manali's position to ensure the document reaches the appropriate reviewers and to push for timely responses.

### 9. Prepare the Document for Submission by Next Wednesday

- Action: Finalize all content revisions and prepare the document for distribution to Grid India by the specified deadline.
- Details:
- Completion: Finish all enhancements in Chapters 3, 4, 5, 6, and 7.
- Quality Check: Proofread the document for errors in grammar, spelling, and technical accuracy.
- Compliance: Verify that the document meets any formatting or submission guidelines required by Grid India or SASEF.

### 10. Expand on Specific Activities as per Stakeholder Feedback

- Action: Based on previous meetings (e.g., with Vivek) and anticipated needs, provide more detailed recommendations in certain areas.
- Details:
- Stability and Resilience Activities: Elaborate on activities that require more specificity, such as:
- Drills and Simulations: Detail the types of resilience drills (e.g., blackstart procedures, load shedding simulations) and expected learning outcomes.
- Operator Training: Specify the skills and knowledge areas that training programs should cover.
- Flexibility Measures: Provide examples of how to enhance grid flexibility, such as demand response programs or energy storage integration strategies.

### 11. Clarify Roles and Responsibilities in the Document

- Action: Clearly outline who is responsible for each activity or recommendation within the roadmap.
- Details:
- Responsible Parties: Identify departments or organizations within Grid India responsible for implementation.
- Collaboration Opportunities: Highlight where external collaboration (e.g., with international experts or technology providers) may be beneficial.

### 12. Ensure Legal and Ethical Compliance

- Action: Review the document to ensure all content complies with legal and ethical standards.
- Details:
- Intellectual Property: Confirm that all sources are properly cited and that permissions are obtained where necessary.
- Confidentiality: Exclude any sensitive information that should not be publicly disclosed.
- Ethical Language: Use culturally sensitive and professional language throughout the document.

### 13. Incorporate Relevant Case Studies or Examples

- Action: Add specific case studies or examples, particularly in Chapters 3, 4, and 5, to illustrate key points.
- Details:
- International Examples (Chapter 3): Include case studies from countries that have successfully integrated IBRs, highlighting lessons learned.
- Technical Solutions (Chapter 4): Provide examples of technical challenges and how they were addressed in other contexts.
- Institutional Solutions (Chapter 5): Showcase effective policy or institutional frameworks that support IBR integration.

### 14. Plan for Post-Review Revisions

- Action: Allocate time and resources for making necessary revisions after receiving feedback from Grid India and other reviewers.
- Details:
- Feedback Integration: Develop a system for tracking comments and implementing changes.
- Version Control: Use a version control system to manage document updates.
- Responsive Communication: Be prepared to respond promptly to reviewer queries or requests for clarification.

### 15. Update Chapters 8 and 9: References and Bibliography

- Action: Ensure all references and bibliographic entries are complete and formatted correctly.
- Details:
- Citation Style: Use a consistent citation style throughout the document (e.g., IEEE, APA).
- Source Verification: Verify that all sources cited are credible and relevant.
- Completeness: Include all sources referenced in the text in the bibliography.

### 16. Prepare for Upcoming Meetings and Deadlines

- Action: Schedule and prepare for the next team meeting on Monday to review the updated draft.
- Details:
- Agenda Setting: Develop an agenda focusing on remaining issues, decisions needed, and status updates.
- Progress Reporting: Be ready to report on completed tasks and any challenges faced.
- Time Management: Ensure the meeting stays focused to make the most of everyone's time.

### 17. Document Task Assignments and Roles

- Action: Clearly define and document responsibilities for each team member moving forward.
- Details:
- Speaker 1's Responsibilities:
- Take the first draft at summarizing Chapters 6 and 7.
- Work on the overall coherence and flow of the document.
- Speaker 2's Responsibilities:
- Focus on enhancing the content in Chapters 3, 4, and 5, specifically elaborating on activities and solutions.
- Ensure technical accuracy and applicability to Grid India's context.
- Collaboration: Maintain open communication to support each other's work and address any issues promptly.

---

Note: The above action items are designed to guide the team in effectively completing the IBR roadmap document, ensuring it meets the needs of Grid India, aligns with project timelines, and adheres to all necessary guidelines and constraints.

If further clarification is needed on any of the action items, or if there are additional tasks to include, please let me know, and I will be happy to assist.

Can you implement the changes above in the draft below:

\chapter{Introduction: India as a Leader in Inverter-Based Resource Deployment}\label{introduction-india-as-a-leader-in-inverter-based-resource-deployment}

India has already made significant strides in deploying Inverter-Based Resources (IBRs), primarily in the form of multi-gigawatt solar photovoltaic (PV) systems. In~addition to large-scale solar, India~is also considered utility-scale battery~energy storage system (BESS) solutions. BESS solutions can provide~grid flexibility~and ancillary services~but may need to concentrate at~the same locations~as the large solar parks. These large-scale deployments have positioned India as a leader in renewable energy and IBR deployment and management within South Asia and beyond. The leadership demonstrates a commitment to grid decarbonization while India's demand grows rapidly with population and prosperity.

This rapid growth also presents potential risks if IBR operation is not properly managed. While IBRs such~as PV and~BESS can be economic technologies to decarbonize and supply electricity, they are fundamentally different~from traditional~generating capacity~that uses~large rotating~machinery and provides the grid with inertia and stability using mechanical~governing systems. IBRs lack physical~inertia and must~instead rely on advanced~controls and~power electronics~to provide ancillary services~in a synthesized manner. When there is a locational concentration of IBR systems, there are potential~risks of large~contingencies and~cascading failures~if IBR synthesized responses are not managed~properly. This~fact is made clear in a recent Grid India \emph{Report on Events Involving Transmission Grid Connected Wind \& Solar Plants}\footnote{December 2023, Grid India, \emph{Report on Events Involving Transmission Grid Connected Wind \& Solar Plants} \emph{{[}URL{]}}}, which describes~31 grid~instability events~from January 2022 to May 2023 where contingencies resulted in several gigawatts of lost generation. The events were broadly classified in five categories (a-e) based on the triggering incidents:

\begin{enumerate}
\def\labelenumi{\alph{enumi})}
\item
  Fault within the renewable energy (RE) plant
\item
  Fault external to the RE plant
\item
  Multiple fault ride-through
\item
  Low frequency voltage and reactive power oscillation
\item
  Over-voltage during the line/reactor switching followed by RE generation loss
\end{enumerate}

For example, Events 1--2 from this report resulted in a loss of nearly 10 GW of renewable energy generation -- following the fault on the 765kV Bhadla-Bikaner ckt1 which triggered a loss of 7.1GW and subsequent loss of additional 2.7GW. Similarly, Events 4--11 resulted in a sequential loss of more than 17 GW of renewable energy generation, following the triggering incident -- Line reactor opened at the Bhadla end of the 765kV Bhadla-Bikaner ckt1. In majority of these events, the severity of the event was exacerbated by the loss of IBR resources at a large scale. Without careful planning and new approaches to IBR integration and operation, India and other grids risk growing challenges maintaining a stable, reliable, and resilient grid.

India needs a clear path to proactively address emerging grid challenges and optimize the benefits of IBRs. The recent Grid India Events Report provides many technical, operational, and institutional actions to improve IBR integration and operation. This IBR integration roadmap seeks to build on these initial recommendations and take a critical and thorough long-term perspective for IBR deployment in the context of uncertain future grid conditions. The roadmap was developed in close collaboration with Grid India, and while it covers some of the same near-term actions of the Grid India Events Report, it offers broader suggestions across institutions and time scales while establishing a structured prioritization across actions in order to satisfy the goals and outcomes set forth by Grid India and the broader India electric sector.

The roadmap is structured to first establish clear goals and outcomes for India IBR deployment to establish the scope of this roadmap. We then provide further motivation for roadmap design by discussing approaches to IBR integration in other countries. The IBR roadmap actions are divided into two broad categories, technical and procedural, to establish specific actionable tasks that can be undertaken. Finally, we establish a rough prioritization of activities into near-term (next 1--2 years), medium term (next 3--5 years), and long term (5+ years) while also identifying stakeholder groups and institutions that may contribute towards fulfilling each action. This roadmap is intended to support accelerated IBR deployment and decarbonization in India so that the country remains a clear leader in IBR utilization for decades to come.

\chapter{Goals and Outcomes of IBR Integration in India}\label{goals-and-outcomes-of-ibr-integration-in-india}

Roadmap actions must be placed in the context of key goals specific to India IBR integration along with the outcomes that would be achieved if those goals are met. The goals represent high-level aspirations for grid planning and operations to support grid stability, strength, reliability, and resiliency. Outcomes demonstrate the positive impacts of achieving these goals along all time scales from near to long term.

\section{Goal: Accelerate India's leadership in grid decarbonization}\label{accelerate-indias-leadership-in-grid-decarbonization}

If IBR integration challenges are not sufficiently addressed, India risks losing its leadership in IBR deployment due to a forced slowdown to ensure grid reliability and other standards are met. Thus, successful long-term roadmapping for IBR integration will ensure it maintains and improves its status as a regional and global leader in IBR integration and decarbonization. Doing so will require a range of technical and non-technical actions. If India is successful, it can set the standard for IBR integration in the South Asia region and beyond, enabling opportunities to help shape IBR integration globally. It can demonstrate India's ability to achieve ambitious decarbonization goals in the midst of unprecedented growth. Domestically, leadership in decarbonization can be a point of pride and demonstrate firm commitment to sustainable growth and the health of human and natural resources.


\section{Goal: Enhance India's ability to reliably integrate variable renewable energy}\label{goal-enhance-indias-ability-to-reliably-integrate-variable-renewable-energy}

Variable renewable energy growth is central to India's energy sector growth and decarbonization strategy, but such growth must occur with continued maintenance and improvement in grid reliability. India has made significant progress in improving and maintaining grid reliability and resource adequacy in a period of rapid growth and initial deployment of variable renewables, primarily PV. It is critical that there be no reversion in this area. BESS has great promise to balance variable renewable energy, especially at diurnal time scales, but it must be properly managed to ensure successful contribution to reliability. Achieving this goal will facilitate continued economic progress, health, and security through stable energy provision. It will ultimately require coordination beyond IBRs that includes distributed and demand-side resources and infrastructure as well as grid operational and market advancements that will also serve to advance India's leadership role in variable renewable and IBR integration.


\section{Goal: Ensure India's grid remains secure and stable}\label{goal-ensure-indias-grid-remains-secure-and-stable}

Grid stability is a critical component to grid reliability that must be emphasized specifically in the context of IBR integration. As stated above, managing short-term static and dynamic stability becomes increasingly difficult with IBR growth and concentration, so it's important to establish specific goals and activities around stability that might not have held as much importance in a grid dominated by thermal generation. Targeted action must be taken to monitor, analyze, and address any issues involving short-term frequency and voltage stability. Doing so is critical to maintain sufficient power quality for device health throughout the grid and avoid larger grid reliability events triggered by instabilities. Success in this area could position India as a global leader in IBR integration and operation, putting it alongside or ahead of other small and large systems that are quickly increasing IBR shares.


\section{Goal: Strengthen India's grid resilience}\label{goal-strengthen-indias-grid-resilience}

Another key goal for IBR integration is to maintain and improve grid resilience, defined as the ability to withstand and recover from any form of disruption that may occur. Such disruptions might arise from unexpected behavior from IBRs themselves, and these must be addressed directly at the source. Regardless of the source of the grid disruption, IBRs can play a key role in restoring grid services, and it is critical to establish how they will do so in a future, deeply decarbonized system. Successful use of IBRs to mitigate grid disruptions could limit damages from longer (e.g., multi-day) outage events and reduce vulnerability to all grid hazards. This goal will be achieved when IBRs are not considered part of the resilience problem but part of the solution.


\section{Goal: Position India's institutions for the grid of the future}\label{goal-position-indias-institutions-for-the-grid-of-the-future}

Successful IBR integration and achieving broader decarbonization and public goals require more than just technical solutions; institutions must be organized for efficient and effective progress towards these goals. Institutional arrangements in India and elsewhere are often well designed for historical, current, and near-term future challenges but sometimes lack flexibility to address rapidly emerging trends as can occur in the space of energy technology and policy. Positioning India's institutions for the future grid means identifying and addressing areas where institutions could adapt to these emerging needs in ways such as cross-institutional collaboration and clarifying responsibilities. If this is done proactively, India will be better able to craft holistic solutions to IBR and other grid challenges, no matter if they are rooted in technology, policy, market, or public needs.


\chapter{International Approaches to IBR Integration}\label{international-approaches-to-ibr-integration}

As renewable energy deployment accelerates worldwide, many countries are taking proactive measures to facilitate higher penetrations of inverter-based resources like solar PV, wind, and battery storage on their grids. While specific policies and initiatives vary, some common themes have emerged:

\section{Grid Code Updates and New Standards}\label{grid-code-updates-and-new-standards}

Recognizing the need for IBRs to contribute to grid stability and reliability, several system operators and regulatory bodies are updating interconnection requirements and grid codes. For example:

\begin{itemize}
\item
  The U.S. Federal Energy Regulatory Commission (FERC) issued Order 2023 directing updates to generator interconnection standards to ensure IBRs can provide essential reliability services like frequency and voltage support.
\item
  The European Network of Transmission System Operators (ENTSO-E) has developed new grid code requirements for grid-forming inverter capabilities to enable very high IBR penetrations.
\item
  Australia\textquotesingle s Energy Security Board is implementing new frequency control and system strength requirements for IBR integration.
\item
  India\textquotesingle s Central Electricity Authority and grid operators like Grid-India are developing a phased roadmap to mandate advanced IBR capabilities like grid-forming controls and synthetic inertia.
\end{itemize}

\section{Research and Modeling Initiatives}\label{research-and-modeling-initiatives}

Improving IBR modeling and analysis capabilities is a priority for many grid operators, research institutions, and industry groups:

\begin{itemize}
\item
  The U.S. Department of Energy launched the Interconnection Innovation e-Xchange (i2X) to advance solutions for faster, lower-cost IBR interconnection.
\item
  The National Renewable Energy Laboratory (NREL) published a research roadmap on grid-forming inverters as an enabler for high IBR shares.
\item
  The Energy Systems Integration Group (ESIG) has facilitated extensive research and knowledge-sharing on IBR stability challenges and mitigation approaches.
\item
  Transmission providers like MISO are developing enhanced screening tools and study practices to better evaluate IBR impacts during interconnection studies.
\end{itemize}

\section{Deployment Incentives and Market Reforms}\label{deployment-incentives-and-market-reforms}

Some jurisdictions are implementing financial incentives and market reforms to accelerate IBR adoption and grid-supportive capabilities:

\begin{itemize}
\item
  The U.S. Inflation Reduction Act includes bonus tax credits for installing wind, solar and storage on brownfields, coal communities and mining sites.
\item
  FERC Order 2023 directs reforms to interconnection pricing that could incentivize IBRs to provide grid services.
\item
  Australia is exploring market rule changes and new ancillary services markets to compensate IBRs for providing essential reliability services.
\item
  The U.K.\textquotesingle s National Grid is developing new procurement mechanisms for stability services from grid-forming IBRs.
\end{itemize}

While challenges remain, these coordinated global efforts across policy, research, markets, and operations aim to unlock the full potential of IBRs in enabling a reliable, resilient, and decarbonized power system.

\begin{figure}[h]
    \centering
    \includegraphics[width=6.5in,height=1.44167in]{./usaid_ibr/media/image5.png}
    \caption{Sample -- Roadmap with Timeline}
    \label{fig:roadmap_timeline}
\end{figure}

\chapter{Technical Challenges and Solutions}\label{technical-challenges-and-solutions}

Technical challenges surrounding IBR integration come in many forms that span a wide range of temporal and scales and involve many aspects of grid planning and operation. Here we organize the discussion of those challenges and their solutions around time scales for which actions are taken, spanning from long-term planning to short-term stability. Components of this discussion are, in practice, highly interrelated with significant overlap across challenges and solutions. This structure is largely intended to highlight clear, actionable strategies for successful IBR integration.

\section{System Adequacy and Planning}\label{system-adequacy-and-planning}

System adequacy means the electric system can meet the current and projected demands reliably. It is achieved through investments in assets that ensure reliable grid operation of the grid over a multi-year under a wide range of uncertain future conditions. IBRs, particularly generators such as PV, introduce complexities in maintaining system adequacy due to their variable nature. To contribute to resource adequacy, IBRs must have a degree of both capacity and energy availability and assurance that can contribute to broader system-wide needs. The system as a whole needs sufficient capacity and energy availability to respond to contingency events and the protection systems in place to adequately detect and isolate faults.

The roadmap activities outlined in this section are intended to achieve several outcomes:

\begin{itemize}
\item
  Improve long-term grid planning tools to better characterize power system resource adequacy and the contributions of IBRs and other variable generation technologies.
\item
  Modernize resource adequacy constructs to address emerging attribute risks through improved IBR modeling, accreditation, and qualification requirements.
\item
  Provide greater visibility into future regional system adequacy needs and capabilities through improved forecasting, planning, and reporting.
\end{itemize}

There are many key tools and approaches for assessing and facilitating resource adequacy. These include:

\begin{itemize}
\item
  \textbf{Capacity Expansion Tools}: Optimization-based or other models and tools that facilitate least-cost or other utility-maximizing objectives for the grid, considering investment decisions among generation, storage, transmission, and other assets including IBRs.
\item
  \textbf{Resource Adequacy Models}: Typically probabilistic tools that examine the degree to which a given grid infrastructure can satisfy demand under uncertain contingency events.
\item
  \textbf{Grid Strength Assessment}: Tools that can evaluate the grid strength when subject to planned changes like IBR deployment, voltage/frequency support devices or IBR controls.
\item
  \textbf{Grid} \textbf{Protectability} \textbf{Assessment}: Tools that evaluate the fault detection, isolation, and coordination capabilities of the protection relays for the grid under different grid-strength conditions and IBR penetrations. These ensure safe operation and protect the equipment and the broader system during severe electrical events.
\end{itemize}

\subsection{Activities}

The following activities aim to improve upon existing tools and approaches to facilitate effective planning for resource adequacy under expected growth in IBR deployment.

\begin{enumerate}
\def\labelenumi{\arabic{enumi}.}
\item
  \textbf{Upgrade capacity expansion and other} \textbf{long-term} \textbf{planning tools} \textbf{to consider investments that can facilitate IBR integration.} These include synchronous condensing either through new or upgraded assets that can provide necessary inertia and support grid strength. Planning models could also better characterize transmission assets and investments that can improve grid stability and strength.
\item
  \textbf{Improve resource adequacy characterization} \textbf{to better assess the capacity credit of IBRs} \textbf{and the contingency events that should be examined to ensure} \textbf{investments to support resource adequacy.} Advanced techniques can estimate capacity credit for variable and energy-limited resources such as PV and BESS, and these should be incorporated into planning and resource adequacy assessment tools while also considering conditions where IBR faults create contingency events.
\item
  \textbf{Develop and apply} \textbf{routines for robust grid strength assessment at multiple scales and resolutions to understand} \textbf{grid strength} \textbf{implications of planned system changes.} These techniques could improve site selection for IBRs, synchronous condensers, and other transmission assets. Embedded within this activity is the critical need to develop a library of standardized and validated IBR models for grid strength assessment, including fault response capabilities. These IBR models will facilitate improved electromechanical and electromagnetic transient analysis of the electric grid.
\item
  \textbf{Use the validated grid and IBR models to} \textbf{characterize grid strength and resource adequacy across a broad range of grid infrastructure and operating conditions.}
\item
  Assess IBR interactions with the grid at both current and forecasted states, incorporating loss of load, generation, and transmission scenarios. In each scenario,
\item
  evaluate fault detection, isolation, and protection coordination of relays at varying grid strengths and IBR proximities. Further
\item
  characterize fault responses (voltage, current, frequency) for protection evaluation and IBR coordination.
\end{enumerate}

\section{Flexibility}\label{flexibility}

Grid flexibility refers to the ability to respond to variability in electricity production and consumption swiftly and efficiently, typically in the context of 5-min to 1-hour time scales. Inverter-based resources (IBRs) like PV and battery storage introduce new forms of variability that must be balanced across multiple timescales \textbackslash cite\{clade\_flexibility\_2021\}. Sufficient flexibility has traditionally been achieved with dispatchable thermal generators that can ramp output up or down as needed to balance energy supply and demand. However, as their share of the generation mix declines, alternative sources of flexibility are required to balance the growing share of variable renewables \textbackslash cite\{denholm\_flexibility\_2016\}. The effective use of IBRs for grid flexibility is an emerging industry practice. For example, power electronics can help PV provide some flexibility. Battery storage is typically even more flexible than thermal generators but must be operated within energy storage capacity constraints, cycling limits, and competing uses for ancillary services.

The roadmap activities outlined in this section are intended to achieve several outcomes:

\begin{itemize}
\item
  Determining the need for emerging flexibility services through expanded and new ancillary service markets.
\item
  Identifying technologies and operating strategies for providing flexibility services in a high-renewable, high-IBR system.
\item
  Enabling emerging IBR technologies to fully participate and provide grid flexibility.
\end{itemize}

There are several key approaches for characterizing and facilitating flexibility in high-IBR systems:

\begin{itemize}
\item
  \textbf{Synthetic Inertia Emulation}: Implementing advanced control algorithms in IBRs to emulate the inertial response traditionally provided by synchronous generators, thus aiding in frequency regulation \textbackslash cite\{eriksson\_synthetic\_2017\}.
\item
  \textbf{Flexibility Needs Assessment}: Quantifying flexibility requirements and resource capabilities under different renewable energy deployment scenarios, informing the optimal mix of battery storage, demand response, and thermal assets \textbackslash cite\{denholm\_flexibility\_2016\}.
\item
  \textbf{Market Incentives Evaluation}: Developing new products and pricing mechanisms that incentivize flexibility, such as pay-for-performance schemes, ramping reserves products, and scarcity pricing \textbackslash cite\{ela\_market\_2014\}.
\item
  \textbf{Distributed Flexibility Utilization}: Leveraging smart grid infrastructure and aggregation platforms to harness the flexibility potential of behind-the-meter distributed energy resources like rooftop PV, electric vehicles, and controllable loads.
\end{itemize}

\subsection{Activities}

The following activities utilize these approaches to maintain and improve grid flexibility in a future where IBRs provide a strong contribution to overall grid energy balancing and ancillary services.

\begin{enumerate}
\def\labelenumi{\arabic{enumi}.}
\item
  \textbf{Establish forward-looking requirements for system inertia and identify assets that could perform synchronous condensing} through upgrades, conversions, or new installation. Explore multiple technology options that can maintain grid strength in the near- to long-term, including IBR controllers that enable synthetic inertia emulation and other grid-supportive functions \textbackslash cite\{eriksson\_synthetic\_2017\}.
\item
  \textbf{Assess the impact of storage technologies on net load ramping requirements} and develop optimized charge/discharge schedules coordinated with renewable generation forecasts; conduct cost-benefit analysis of storage for providing frequency regulation, operating reserves, and other ancillary services \textbackslash cite\{denholm\_flexibility\_2016\}. Perform this assessment at the state-to-local level to consider locational differences in grid topology and storage system needs.
\item
  \textbf{Optimize energy and ancillary service market designs} to enable storage, demand response, and distributed energy resources to better participate; develop appropriate performance requirements, compensation structures, and ancillary service products to address emerging flexibility needs while reducing system costs \textbackslash cite\{enel\_flexibility\_2023\} \textbackslash cite\{ela\_market\_2014\}.
\end{enumerate}

By proactively assessing flexibility needs, harnessing the capabilities of battery storage and other IBRs, and reforming operational practices and market structures, India can efficiently integrate high IBR shares. This will require close coordination between system operators, power markets, aggregators, and flexibility providers. Robust price signals and enabling regulatory frameworks are essential to drive investment in flexibility and reward performance \textbackslash cite\{enel\_flexibility\_2023\}. With the right mix of flexible resources and mechanisms, India can reliably balance supply and demand in an IBR-dominant grid.

\section{Stability}\label{stability}

Grid stability relates to its ability to maintain steady voltage and frequency within acceptable ranges and return to a steady-state condition within these ranges after a disturbance without cascading failures \textbackslash cite\{kundur\_definition\_1994\}. With rising shares of IBRs, maintaining stability becomes more challenging due to reduced system inertia, potential oscillatory behavior, and unexpected tripping during disturbances \textbackslash cite\{flynn\_stability\_2017, nerc\_ibr\_2020\}.

The roadmap activities outlined in this section are intended to achieve several outcomes:

\begin{itemize}
\item
  Facilitating the development and deployment of detailed models and tools that assess IBR impacts on system stability, characterize emerging risks, and identify mitigation measures.
\item
  Strengthening IBR frequency response characteristics and ensuring IBRs provide adequate voltage control and reactive power support \textbackslash cite\{eriksson\_synthetic\_2017\}.
\item
  Mitigating sub-synchronous oscillations and control interactions between IBRs and other grid management systems \textbackslash cite\{wang\_ssci\_2016\}.
\item
  Enhancing ride-through performance to avoid tripping or cessation of active power during disturbances \textbackslash cite\{nerc\_ibr\_2018\}
\end{itemize}

Key approaches that help describe and improve grid stability with high IBR shares include:

\begin{itemize}
\item
  \textbf{Enhancing Stability Analysis Capabilities}: Developing and validating high-fidelity, vendor-specific IBR dynamic models for small-signal and transient stability studies. Conducting comprehensive assessments across deployment scenarios, contingencies, and mitigation options to identify regional stability limits and critical IBR performance requirements \textbackslash cite\{vittal\_ssci\_2019, ramasubramanian\_ibr\_2020\}.
\item
  \textbf{Refining Grid-Forming Inverter Deployment}: Deploying grid-forming inverters that can independently maintain voltage and frequency stability, provide synthetic inertia, and enable stable grid operation at very high IBR shares. Establishing performance requirements and conduct pilot demonstrations to evaluate and refine capabilities \textbackslash cite\{matevosyan\_gfi\_2019\}.
\item
  \textbf{Implementing Advanced IBR Controls}: Developing and mandating advanced control functions like fast frequency response, power oscillation damping, and adaptive voltage/reactive control to enhance stability. Updating interconnection requirements, grid codes, and standards to ensure IBR capabilities align with evolving grid needs \textbackslash cite\{shah\_ffr\_2019, ieee\_p2800\_2021\}.
\end{itemize}

\subsection{Activities}

The following activities use these approaches to maintain and improve grid stability as IBR deployment accelerates.

\begin{enumerate}
\def\labelenumi{\arabic{enumi}.}
\item
  \textbf{Develop and validate high-fidelity, vendor-specific IBR dynamic models} for small-signal and transient stability studies, in close coordination with manufacturers \textbackslash cite\{ramasubramanian\_ibr\_2020\}.
\item
  \textbf{Conduct comprehensive system stability assessments across a range of possible scenarios}, including IBR deployment scenarios, contingency events, and mitigation options. Identify regional stability limits and critical IBR performance requirements.
\item
  \textbf{Establish forward-looking frequency response requirements} and incentivize fast frequency response and synthetic inertia capabilities from new and existing IBRs \textbackslash cite\{eirgrid\_ffr\_2020\}.
\item
  \textbf{Deploy pilot projects that demonstrate advanced IBR capabilities} like grid-forming inverters, fast frequency response, power oscillation damping, and adaptive voltage control. Evaluate performance and refine requirements.
\item
  \textbf{Update interconnection requirements, grid codes, and standards} (e.g. IEEE P2800) to mandate key IBR capabilities for stability, including fault ride-through, dynamic voltage support, and frequency response \textbackslash cite\{ieee\_p2800\_2021\}.
\item
  \textbf{Enhance real-time situational awareness and decision support tools} for operators to quickly detect and mitigate emerging stability risks in high-IBR conditions.
\end{enumerate}

By implementing these stability measures, India can operate the grid reliably even with very high shares of IBRs. Close collaboration between grid operators, planners, IBR developers, and manufacturers to analyze, demonstrate and deploy advanced capabilities will be critical to maintaining a stable grid through the clean energy transition.

\section{Resilience}\label{resilience}

Resilience refers to the grid\textquotesingle s ability to withstand and recover from major disruptions such as extreme weather events, cyberattacks, or equipment failures \textbackslash cite\{NREL\_resilience\_2021\}. While closely related to reliability, resilience focuses on mitigating the consequences of low-probability, high-impact events. The growing frequency and severity of extreme weather events poses a significant threat to India\textquotesingle s power grid resilience, with several major blackouts triggered by such events in recent years \textbackslash cite\{Cyclone\_Amphan\_2020\}.

The roadmap activities outlined in this section are intended to achieve several outcomes:

\begin{itemize}
\item
  Enable the creation of comprehensive contingency plans considering IBR characteristics, fuel dependencies, and cyber-vulnerabilities.
\item
  Establish pathways for IBRs to provide black start and restoration services that can quickly re-energize the grid post-disturbance.
\item
  Improve wide-area monitoring, protection, and control schemes to successfully contain cascading outages while maintaining bulk power transfer paths.
\item
  Facilitate the development and deployment of grid-enhancing technologies that improve IBR integration and grid resilience.
\end{itemize}

There are several key approaches for enhancing grid resilience in high-IBR systems:

\begin{itemize}
\item
  \textbf{Resilience-by-Design}: This refers to infrastructure hardening that improves grid resilience. Hardening IBR infrastructure against threats like extreme weather can be achieved in many ways, such as flood-proofing, fire protection, and undergrounding critical equipment \textbackslash cite\{NREL\_resilient\_RE\_2021\}.
\item
  \textbf{Grid-Forming Inverters}: Grid-forming inverters could independently maintain voltage and frequency stability during disturbances and enable islanded operation \textbackslash cite\{NREL\_GFM\_roadmap\_2022\}.
\item
  \textbf{Microgrids and DERs}: IBR-rich microgrids and distribution systems can disconnect and operate autonomously during bulk grid outages to sustain critical loads \textbackslash cite\{LBNL\_microgrid\_2018\}.
\end{itemize}

\subsection{Activities}

The following activities aim to leverage the growing proliferation of IBRs to build a more resilient power system:

\begin{enumerate}
\def\labelenumi{\arabic{enumi}.}
\item
  \textbf{Conduct wide-area resilience studies} to identify critical nodes, common failure modes, and regional interdependencies under a wide range of potential hazards and severity. Then develop cohesive mitigation strategies that address a broad spectrum of hazards while maintaining cost effectiveness.
\item
  \textbf{Design market mechanisms and/or} \textbf{regulatory frameworks} \textbf{that} \textbf{incentivize} \textbf{investments} \textbf{that improve grid resilience}. For existing and new market and regulatory frameworks, develop methods to compensate IBRs and other flexible technologies for grid-enhancing services.
\item
  \textbf{Develop technical standards and interconnection requirements} that mandate key resilience capabilities for new IBRs, such as ride-through, grid-forming, and black start.
\item
  \textbf{Implement distributed energy resource management systems (DERMS) and predictive outage management tools} that leverage IBRs for system restoration.
\item
  \textbf{Establish cybersecurity standards and compliance procedures for IBRs} to mitigate risks during normal and degraded grid conditions.
\item
  \textbf{Conduct regular resilience drills and simulations} to train operators and identify areas for improvement in IBR-dominant grids.
\end{enumerate}

By proactively implementing these resilience strategies and solutions, India can leverage the growing shares of IBRs to build a power system that is more robust against the rising threats of hazards such as extreme weather and cyberattacks. Close coordination between policymakers, regulators, grid operators, IBR developers, and research institutions will be key to prioritizing and staging the required investments and regulatory reforms. Integrating resilience considerations into every stage of the clean energy transition is critical to delivering reliable, sustainable, and affordable power while safeguarding public safety and economic security.


\chapter{Institutional Challenges and Solutions}\label{institutional-challenges-and-solutions}

Integrating high~shares of inverter-based resources~(IBRs) into the~grid requires~more than just~technical solutions. Re-evaluation of the Procedural and institutional~policies may facilitate a~smooth transition. This section~explores key~procedural challenges~and potential~solutions across~integrated planning, operator coordination, and grid standards.

\section{Integrated Planning}\label{integrated-planning}

Integrated planning involves holistically assessing generation, transmission, and distribution needs to optimize investments and ensure grid reliability with rising IBR shares. It requires close coordination between multiple stakeholders including central and state agencies, grid operators, generators, and distribution companies.

\subsection{Key activities:}

\begin{itemize}
\item
  Establish methods for integrating investment planning for grid strengthening components (synchronous condensers, STATCOMs, etc.) with generation and transmission planning to achieve a holistic integrated planning approach.
\item
  Develop modeling procedures, metrics, and processes to co-optimize generation and transmission expansion considering IBR variability, grid strength needs, and flexibility requirements.
\item
  Implement regulatory frameworks that incentivize coordinated planning across the electricity value chain rather than siloed decision-making.
\item
  Build institutional capacity and knowledge sharing platforms to enable effective integrated planning practices at the central and state level.
\item
  Proactively augment transmission infrastructure and deploy grid-strengthening solutions in renewable-rich areas through integrated generation-transmission planning
\item
  Streamline processes to enable rapid deployment of utility-scale renewable energy parks and distributed IBRs in line with India\textquotesingle s ambitious 500 GW non-fossil target by 2030
\item
  Clearly delineate roles and responsibilities for central and state agencies in maintaining reliability during the energy transition
\item
  Promote cross-institutional collaboration and knowledge sharing with states, industry and global partners to adopt best practices
\end{itemize}

\section{Operator Coordination}\label{operator-coordination}

As the grid transitions from centralized synchronous generation to distributed IBRs, close coordination between grid operators at the national, regional, and state level becomes critical. Real-time data sharing, aligned operating procedures, and clear roles and responsibilities are essential for managing the complexity.

\subsection{Key activities:}

\begin{itemize}
\item
  Establish clear protocols for coordination and data sharing across grid dispatch operators at various scales and jurisdictions, including event records and detailed operational data.
\item
  Harmonize scheduling, dispatch, and settlement procedures across regions to facilitate efficient renewable energy integration and enable balancing over larger areas.
\item
  Determine what system and market data must be shared or made public for asset owners and operators to enable cost-optimal and reliable system operation.
\item
  Conduct regular operator training and knowledge exchange programs to build capacity for managing high-IBR grids.
\item
  Establish processes to regularly report on grid performance metrics, progress on IBR integration, and mitigation of emerging challenges
\end{itemize}

\section{Grid Standards}\label{grid-standards}

Robust technical standards allow a diverse group of stakeholders to integrate IBRs in a reliable and sustainable manner into the grid. India should evaluate its standards framework to expand upon the specifications of grid-friendly capabilities and measures to mandate compliance by all IBR assets. If necessary, international standards like IEEE 1547-2018 and IEEE 2800 may be considered for additional perspectives.

\subsection{Key activities:}

\begin{itemize}
\item
  Evaluate existing standards and grid codes to determine the capabilities of the state-of-the-art IBRs towards voltage/frequency ride-through, dynamic reactive support, active power control, etc.
\item
  Develop and enforce mechanisms to ensure that IBRs comply with grid codes and standards, including validation procedures and mechanisms for coordinating directly with IBR developers to improve performance.
\item
  Establish dedicated standards for emerging technologies critical for IBR integration, such as grid-forming inverters, battery energy storage, hybrid plants, etc.
\item
  Actively participate in international standards development bodies to align with global best practices and contribute to the standards making process.
\item
  Adopt grid codes mandating advanced grid-support capabilities for new IBRs to provide voltage/frequency support as conventional plants retire
\end{itemize}

Evaluating these procedural challenges through policy, regulatory and institutional reforms can accelerate India\textquotesingle s ambitious efforts to achieve its renewable energy targets. An integrated approach spanning planning, operations, and standards will help optimize investments, improve grid efficiency and reliability, and accelerate the clean energy transition.


\chapter{Prioritization of Key Challenges and Activities}\label{prioritization-of-key-challenges-and-activities}

This roadmap is structured to prioritize the key actions based on the timeline of needs:

\begin{itemize}
\item
  Immediate term (1-2 years): Focus on actions to manage transmission expansion, renewable integration and grid strength during the ongoing transition
\item
  Medium term (3-5 years): Prepare for emerging needs such as enhanced IBR capabilities, market reforms and operational tools
\item
  Long term (5+ years): Proactively address issues like declining inertia and advanced grid-forming technologies
\end{itemize}

\section{Near-Term Priorities (1-2 years)}\label{near-term-priorities-1-2-years}

\subsection{Transmission Expansion and Technology Evaluation}

\begin{itemize}
\item
  Conduct detailed studies to compare HVDC and AC options for evacuating power from renewable-rich areas, considering system strength, losses and cost
\item
  Identify priority transmission corridors and implement grid-strengthening measures like synchronous condensers in weak pockets
\item
  Develop state-level transmission plans in coordination with renewable deployment targets
\end{itemize}

\subsection{Renewable Integration and Grid Code Enhancements}

\begin{itemize}
\item
  Assess regional grid strength (SCR) and identify areas with potential voltage stability risks
\item
  Update grid interconnection requirements for IBRs to provide voltage and frequency support
\item
  Pilot projects to demonstrate grid-forming inverter technology and inform future standards
\end{itemize}

\subsection{Storage Deployment for Ancillary Services}

\begin{itemize}
\item
  Conduct detailed cost-benefit analysis of battery storage for frequency regulation and other ancillary services
\item
  Develop a state-wise roadmap for battery storage deployment in coordination with renewable procurement plans
\item
  Implement mechanisms for storage to participate in ancillary service markets on a pilot basis
\end{itemize}

\section{Medium-Term Priorities (3-5 years)}\label{medium-term-priorities-3-5-years}

\subsection{Advanced IBR Capabilities}

\begin{itemize}
\item
  Establish requirements for grid-forming capability for new IBRs
\item
  Develop a national roadmap to retrofit existing IBRs with advanced controls
\item
  Pilot hybrid renewable + storage projects to provide virtual inertia and fast frequency response
\end{itemize}

\subsection{Ancillary Service Market Reforms}

\begin{itemize}
\item
  Implement co-optimized energy and ancillary service markets at the regional level
\item
  Enable demand response, distributed energy resources and storage to provide reserves
\item
  Explore innovative service products such as fast frequency response and inertia
\end{itemize}

\subsection{Operational Tools and Processes}

\begin{itemize}
\item
  Develop and deploy wide-area monitoring systems to observe IBR response in real-time
\item
  Enhance dynamic system models with accurate IBR characteristics for online security assessment
\item
  Implement operator tools and training programs to manage high-IBR conditions
\end{itemize}

\section{Long-Term Priorities (5+ years)}\label{long-term-priorities-5-years}

\subsection{Inertia Management}

\begin{itemize}
\item
  Conduct detailed studies on regional inertia requirements and trends with increasing IBRs
\item
  Pilot synchronous condensers and other technologies to provide local inertia support
\item
  Explore alternate frequency response metrics and requirements suitable for low-inertia grids
\end{itemize}

\subsection{Grid-Forming Technology Roadmap}

\begin{itemize}
\item
  Develop a long-term roadmap for transitioning to grid-forming IBRs as the default
\item
  Collaborate with manufacturers on next-generation grid-forming controls and protection
\item
  Conduct detailed system stability analysis to determine grid-forming inverter requirements
\end{itemize}

\subsection{Microgrids and Distributed Energy Resources}

\begin{itemize}
\item
  Develop a comprehensive framework for integrating microgrids and DERs into grid operations
\item
  Pilot advanced microgrid controllers with grid-forming capabilities to enhance resilience
\item
  Implement retail market reforms to incentivize DER aggregation and virtual power plants
\end{itemize}

\chapter{Roadmap Summary}\label{roadmap-summary}

The table below summarizes the key activities identified in this roadmap and maps them to relevant stakeholder categories and specific entities in the Indian context. Coordinated action by these stakeholders, guided by the recommendations herein, can help India efficiently integrate high shares of inverter-based resources and emerge as a global leader in renewable energy.

\begin{longtable}[]{@{}
  >{\raggedright\arraybackslash}p{(\linewidth - 4\tabcolsep) * \real{0.2726}}
  >{\raggedright\arraybackslash}p{(\linewidth - 4\tabcolsep) * \real{0.3937}}
  >{\raggedright\arraybackslash}p{(\linewidth - 4\tabcolsep) * \real{0.3337}}@{}}
\toprule\noalign{}
\begin{minipage}[b]{\linewidth}\raggedright
Activity
\end{minipage} & \begin{minipage}[b]{\linewidth}\raggedright
Key Participant Types
\end{minipage} & \begin{minipage}[b]{\linewidth}\raggedright
Key Entities in India
\end{minipage} \\
\midrule\noalign{}
\endhead
\bottomrule\noalign{}
\endlastfoot
Planning Grid Strength Assessment & Grid Operators, Planners, Researchers & CEA, CTU, STUs, GRID-INDIA, NREL \\
Synchronous Condensers & Grid Operators, Generators, Researchers & CEA, CTU, STUs, NTPC, NHPC, NREL \\
Protectability of the Grid & Grid Operators, Researchers, Equipment OEMs & CEA, CTU, STUs, GRID-INDIA, NREL, Protection and SCADA Vendors \\
Synthetic Inertia & Grid Operators, Researchers, IBR Developers & GRID-INDIA, SLDCs, NREL, IBR Manufacturers \\
Disturbance Modeling \& Analysis & Grid Operators, Researchers & GRID-INDIA, Academia, NREL \\
Contingency Modeling \& Analysis & Grid Operators, Planners & GRID-INDIA, CTU, STUs \\
Operational Grid Strength Assessment & Grid Operators, Researchers & GRID-INDIA, SLDCs, NREL \\
Grid-Forming Inverters & Grid Operators, IBR Developers, Researchers, Site owners & GRID-INDIA, NREL, IBR Manufacturers, Site-Owners \\
Integrated Planning & Policymakers, Planners, Regulators & MoP, CEA, CERC, SERCs \\
Operator Coordination & Grid Operators & GRID-INDIA, RLDCs, SLDCs \\
Grid Standards & Policymakers, Regulators, Researchers & MoP, CEA, CERC, NREL \\
\end{longtable}

\emph{CEA - Central Electricity Authority}

\emph{CTU - Central Transmission Utility}

\emph{STU - State Transmission Utility}

\emph{NREL - National Renewable Energy Laboratory}

\emph{NTPC -- National Thermal Power Corporation}

\emph{NHPC -- National Hydro Power Corporation}

\emph{MoP - Ministry of Power}

\emph{CERC - Central Electricity Regulatory Commission}

\emph{SERC - State Electricity Regulatory Commission}

\emph{RLDC -- Regional Load Dispatch Center}

\emph{SLDC -- State Load Dispatch Centers}

Technologies like grid-forming inverters and synchronous condensers provide unique opportunities to strengthen the grid and ensure stable operation with high shares of renewable energy. India's planning and operation procedures and grid standards may be re-evaluated to optimize infrastructure investments and enhance coordination. By engaging the diverse stakeholders in India, the country can accelerate its ongoing energy transition and achieve a reliable, affordable and sustainable electricity future.

\chapter{References}\label{references}


\chapter{Bibliography}\label{bibliography}


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