Must-Run Status

What Is Must-Run Status?

Must-run status is the regulatory protection granted to renewable energy plants that mandates priority dispatch and prohibits or strictly limits curtailment by grid operators. In India, solar, wind, small hydro, biomass, and other renewable sources carry must-run status under the combined framework of the Electricity Act 2003, MNRE notifications, CERC regulations, and State Grid Codes.

The principle is straightforward: renewable energy is variable and must be consumed when generated. Unlike coal or gas plants that can throttle output on command, solar and wind generation depends on real-time weather. Curtailing renewables wastes zero-fuel energy, increases system costs, and undermines the economic viability of projects that were financed based on expected generation volumes.

Must-run status was formalised in the Electricity Act 2003, which established renewable priority in the national electricity framework. The protection was significantly strengthened by a 2019 MNRE notification that explicitly directed all SLDCs (State Load Despatch Centres) to treat solar and wind as must-run plants. CERC and State Electricity Regulatory Commissions (SERCs) implement the framework through specific regulations, while individual Power Purchase Agreements (PPAs) embed must-run clauses and deemed generation compensation provisions.

For solar developers, must-run status is not a minor legal detail, it is a foundational element of project finance. Lenders assess must-run protection during due diligence, and its absence or weakness can prevent financial closure. For DISCOMs, must-run status imposes an obligation to absorb renewable generation or compensate developers for curtailment that falls outside strictly defined exceptions.

Important: Must-run status does not mean renewables can never be curtailed. It means curtailment is permitted only for grid security, force majeure, or scheduled maintenance, and that unjustified curtailment triggers compensation at the full PPA tariff.

Why Must-Run Status Matters

Must-run status matters because it protects the revenue stream that underpins every renewable energy investment. Solar projects in India are typically financed with 70-80% debt over 15-20 year tenors. Debt service depends on predictable cash flows from energy sales. Curtailment without compensation destroys those cash flows and can trigger loan defaults.

Revenue protection: When a 100 MW solar plant is curtailed for 100 hours annually, the lost generation at Rs 2.50/kWh amounts to approximately Rs 2.5 crore in lost revenue. Must-run status with deemed generation compensation ensures the developer still receives payment, preserving project economics.

Lender confidence: Financial institutions including PFC, REC, IREDA, and private banks require must-run protection as a standard lending condition. Strong must-run provisions reduce the risk premium on project debt, lowering financing costs and improving returns.

Investment climate: Consistent must-run enforcement signals policy stability to domestic and international investors. India attracted over $20 billion in renewable energy investment between 2020 and 2025, much of it contingent on regulatory protections including must-run.

Grid integration: By mandating renewable absorption, must-run status accelerates the transition away from fossil fuels. It forces grid operators to invest in flexibility solutions, transmission capacity, and demand-side management rather than defaulting to curtailment.

Consumer benefit: Ultimately, must-run status ensures that the cheapest source of electricity, solar and wind, reaches consumers. Curtailment of low-cost renewables forces DISCOMs to buy more expensive thermal power, raising electricity bills.

How Must-Run Status Works

The must-run framework operates through a layered mechanism involving legislation, regulation, contracts, and enforcement.

Legislative foundation: The Electricity Act 2003 establishes the National Electricity Policy and National Tariff Policy, both of which articulate renewable promotion as a national priority. Section 86(1)(e) empowers SERCs to promote cogeneration and generation of electricity from renewable sources.

Central notification: The 2019 MNRE notification on must-run status directed all SLDCs to issue operational instructions treating solar and wind power as must-run. This notification applies across all states and union territories, overriding any contrary state-level practices.

Regulatory implementation: CERC issues regulations for inter-state transmission and central-sector projects. SERCs issue state-specific regulations that define must-run obligations for intra-state projects. State Grid Codes operationalise these regulations with specific technical criteria for permissible curtailment.

Contractual embedding: PPAs between developers and off-takers (typically DISCOMs or SECI) include explicit must-run clauses. These clauses reference applicable regulations, define deemed generation calculation methodology, specify compensation at PPA tariff, and establish dispute resolution forums.

Operational enforcement: SLDCs are the first line of enforcement. They must document all curtailment events with justification. Developers monitor curtailment through SCADA and met station data. When unjustified curtailment occurs, developers file claims with the off-taker, escalate to SERC if disputed, and can appeal to APTEL.

Compensation mechanism: Deemed generation provisions calculate lost energy based on pyranometer data, comparable plant performance, or forecast methods. The developer is paid at the contracted PPA tariff for the curtailed energy, typically through monthly billing adjustments or separate settlement mechanisms.

Visual Explanation

Real-World Example

In 2019, the Andhra Pradesh government attempted to renegotiate solar and wind PPAs signed between 2015 and 2017, citing high tariffs. The state argued that tariffs of Rs 4.50 to Rs 5.50/kWh were uncompetitive compared to newer bids at Rs 2.50/kWh. As part of this move, the state also challenged must-run protections, effectively curtailing renewable generation without compensation.

Solar and wind developers filed petitions with APTEL, arguing that the renegotiation violated the sanctity of contract and the must-run framework. APTEL ruled in favour of the developers, upholding the original PPAs and must-run protections. The Supreme Court subsequently declined to interfere with APTEL’s order.

The financial impact was substantial. Developers with 5,000+ MW of capacity in Andhra Pradesh faced revenue uncertainty during the 18-month dispute. Lenders halted disbursements for new projects in the state. The case demonstrated that must-run status, while legally robust, requires active vigilance and litigation to enforce against state-level challenges.

For Gujarat-based developers, the Andhra Pradesh case reinforced the importance of strong PPA drafting, robust data infrastructure for curtailment documentation, and engagement with industry associations like NSEFI and ISMA for collective defence of must-run protections.

Technical Specifications / Benchmarks

Benefits / Advantages

1. Revenue certainty: Developers receive payment for all generation, actual or deemed, ensuring predictable cash flows for debt service and investor returns.

2. Lower cost of capital: Strong must-run protection reduces lender risk perception, enabling lower interest rates and longer debt tenors.

3. Investment attraction: Consistent regulatory protection signals policy stability, attracting domestic and foreign investment into Indian renewables.

4. Grid modernisation pressure: By prohibiting easy curtailment, must-run forces grid operators to invest in transmission, storage, and demand response.

5. Consumer savings: Absorbing the cheapest electricity (solar and wind) rather than curtailing it and buying expensive thermal power reduces average power purchase costs.

6. Climate commitment support: Must-run status ensures that India’s 500 GW renewable target by 2030 translates into actual generation, not just installed capacity.

7. Contract sanctity: The framework reinforces the rule of law in power sector contracts, preventing arbitrary state-level renegotiation.

8. Technology neutrality: Must-run applies to all renewable technologies, allowing market forces to determine the optimal generation mix.

Limitations / Drawbacks

1. Grid stability tension: As renewable penetration crosses 30-40%, mandatory absorption conflicts with grid stability requirements. Flexibility investments lag behind renewable deployment.

2. Slow compensation: Deemed generation claims often face delays of 3 to 12 months, straining developer cash flows even when the legal right to compensation exists.

3. Enforcement variability: Some states enforce must-run more rigorously than others. Gujarat and Rajasthan generally comply well; other states have poorer track records.

4. Documentation burden: Developers must maintain detailed SCADA and met station records to prove curtailment events and quantify losses. This requires ongoing investment in data infrastructure.

5. State-level challenges: Occasional attempts by state governments to renegotiate PPAs or weaken must-run protections create legal uncertainty, as seen in Andhra Pradesh and Tamil Nadu.

6. Definition disputes: What constitutes “grid security” or “force majeure” can be contested, leading to prolonged litigation.

Comparison: Must-Run vs. Other Dispatch Mechanisms

Applications

Residential rooftop solar: Must-run status applies indirectly. Net metering regulations, which vary DISCOM by DISCOM, require most utilities to credit all exported generation. Curtailment of rooftop exports is rare but can occur in areas with high penetration and weak distribution infrastructure.

Commercial and industrial (C&I) solar: Open-access and captive solar projects benefit from must-run status in their wheeling agreements. However, open-access regulations vary by state, and some states impose banking restrictions that functionally limit must-run benefits.

Utility-scale solar: The primary beneficiary of must-run status. Large solar parks with long-term PPAs to SECI or state DISCOMs rely on must-run for revenue certainty. Lender covenants explicitly reference must-run protections.

Wind and hybrid projects: Wind projects have had must-run status longer than solar. Hybrid solar-wind projects benefit from combined must-run protection, though dispatch complexity increases with multiple generation sources.

Battery storage: Standalone battery storage does not have must-run status. However, solar-plus-storage projects may see must-run extended to the solar component, with storage providing grid services that support absorption.

Industry Standards & Regulations

Must-run status is governed by a multi-layered legal and regulatory framework:

• Electricity Act, 2003: The foundational legislation establishing renewable priority and regulatory authority.
• National Electricity Policy, 2005: Articulates the policy objective of promoting renewable energy.
• National Tariff Policy: Defines tariff structures and renewable purchase obligations supporting renewables.
• MNRE Notification, 2019: Specifically directs SLDCs to treat solar and wind as must-run plants.
• CERC Regulations: Central regulator’s framework for inter-state renewable dispatch, including must-run provisions.
• SERC Regulations: State-level implementation. Each state regulator issues specific orders embedding must-run in state Grid Codes.
• State Grid Codes: Operational rules that define permissible curtailment circumstances and documentation requirements.
• PPA Documents: Individual project contracts that reference must-run regulations and specify deemed generation compensation.
• APTEL and Supreme Court Orders: Judicial precedents that reinforce must-run protections and clarify ambiguities.

In Gujarat, the Gujarat Electricity Regulatory Commission (GERC) has generally upheld must-run protections, contributing to the state’s status as a preferred destination for solar investment.

Engineering and permitting teams tracking this fast-moving regulatory landscape alongside interconnection and compliance requirements can reference Heaven Designs’ solar compliance resource center for state-by-state regulatory updates.

India-Specific Context

India’s must-run framework has evolved alongside its renewable energy ambitions. In the early National Solar Mission phases (2010-2015), must-run was less formalised, and curtailment was common in states with surplus thermal capacity. Developers absorbed losses or pursued slow-moving regulatory remedies.

The 2019 MNRE notification marked a turning point by explicitly directing all SLDCs to issue must-run instructions. This central directive reduced state-level variation, though enforcement remains uneven.

Gujarat has been a leader in must-run compliance. The state’s high renewable penetration (over 15 GW of solar and wind) has forced GETCO and state DISCOMs to invest in transmission infrastructure and grid management systems. The result is one of India’s lowest curtailment rates for renewable energy.

Rajasthan, with even higher renewable capacity, has faced more curtailment challenges due to transmission constraints. The Green Energy Corridors project, funded by the Ministry of Power, aims to address these constraints and restore full must-run feasibility.

Tamil Nadu and Andhra Pradesh have had more contentious must-run histories, with state governments occasionally attempting to override central directives. APTEL has consistently ruled in favour of developers, but the litigation imposes costs and delays.

Future Trends

As India approaches its 280 GW solar target within the 500 GW renewable goal by 2030, must-run status faces three structural challenges:

1. High penetration grid management: With renewable share projected to exceed 40% by 2030, the physical ability to absorb all generation will depend on massive investments in transmission, storage, and demand response. Must-run status must evolve from a simple dispatch mandate to a framework that incentivises flexibility.

2. Market integration: As India deepens its power markets (day-ahead, real-time, green markets), must-run may need to coexist with market-based dispatch. The challenge is to maintain renewable priority while allowing price signals to guide efficient system operation.

3. Storage and hybridisation: Solar-plus-storage projects can provide grid services that reduce the need for curtailment. Future must-run frameworks may condition priority dispatch on the provision of ancillary services, creating a more collaborative relationship between renewables and grid operators.

4. Regional coordination: Inter-state transmission and regional load despatch centres will play a larger role in managing renewable variability. Must-run enforcement may shift from state-level SLDCs to regional entities with broader system visibility.

Common Mistakes & Misconceptions

1. Assuming must-run means zero curtailment: Must-run permits curtailment for grid security, force majeure, and maintenance. Developers must understand the exceptions and document when curtailment falls outside them.

2. Weak PPA drafting: Generic must-run clauses without specific deemed generation calculation methods create disputes. Strong PPAs define the formula, data sources, and settlement timeline.

3. Inadequate data infrastructure: Without SCADA and met station records, developers cannot prove curtailment events or quantify losses. Data infrastructure is as important as legal protection.

4. Delayed compensation claims: Waiting months to file deemed generation claims weakens the legal position. Prompt documentation and escalation are essential.

5. Ignoring state-level variation: Must-run enforcement varies by state. Developers in multiple states must track SERC orders and SLDC practices separately.

6. Confusing must-run with open access: Open-access regulations govern the physical wheeling of power and may include banking restrictions. Must-run governs dispatch priority. The two interact but are distinct.

7. Underestimating litigation costs: Enforcing must-run against recalcitrant off-takers requires legal resources. Budget for regulatory and appellate litigation as a cost of doing business.

8. Neglecting lender communication: Lenders monitor must-run compliance closely. Proactive communication about curtailment events and compensation claims maintains lender confidence.

Key Takeaways

• Must-run status is the regulatory protection that mandates priority dispatch and restricts curtailment of renewable energy plants to strictly defined technical circumstances.
• The framework rests on the Electricity Act 2003, the 2019 MNRE notification, CERC/SERC regulations, and State Grid Codes.
• Solar, wind, small hydro, and biomass plants typically have must-run status in India.
• Permitted curtailment is limited to grid security, force majeure, and scheduled maintenance; all other curtailment triggers deemed generation compensation.
• Deemed generation compensates developers at the full PPA tariff for unjustified curtailment.
• Enforcement involves SLDCs, SERCs, CERC, APTEL, and the Supreme Court.
• Strong must-run protection reduces financing costs, attracts investment, and ensures consumer access to low-cost renewable power.
• Gujarat has been a leader in must-run compliance, contributing to its status as India’s top solar state.
• Future challenges include managing must-run with 40%+ renewable penetration and integrating must-run with evolving power markets.
• Developers must invest in data infrastructure and strong PPA drafting to realise the full benefit of must-run protection.

Frequently Asked Questions

Q1: What is must-run status? Must-run status is regulatory protection that requires the grid to accept generation from designated renewable plants without curtailment, except under strictly defined technical circumstances.

Q2: Which plants have must-run status in India? Solar, wind, small hydro (under 25 MW), biomass, and other renewable sources have must-run status under MNRE and CERC regulations.

Q3: When was must-run formalised? The Electricity Act 2003 established renewable priority. The 2019 MNRE notification specifically strengthened must-run protection for renewables.

Q4: When can must-run plants be curtailed? Only for grid stability issues, force majeure events, and scheduled maintenance. All other curtailment is illegal and triggers compensation.

Q5: What is deemed generation? Compensation paid to developers at the PPA tariff when curtailment occurs despite must-run protection. Lost generation is calculated from plant data.

Q6: How is must-run enforced? Through SLDCs, SERCs, CERC, and APTEL. Developers document curtailment and file claims, escalating to regulators and courts as needed.

Q7: Does must-run apply to rooftop solar? Indirectly, through net metering regulations that require DISCOMs to credit all exported generation.

Q8: How does must-run affect financing? Lenders require must-run protection as a standard condition. Strong protection reduces risk and lowers financing costs.

Q9: Has must-run been challenged? Yes, notably in Andhra Pradesh in 2019. APTEL and the Supreme Court have generally upheld must-run protections.

Q10: What is the future of must-run? As renewable penetration grows, must-run must be balanced with grid stability. Storage, demand response, and transmission investments are essential.

Q11: Do all states enforce must-run equally? No. Gujarat and Rajasthan generally comply well. Other states have had more contentious enforcement histories.

Q12: What should developers do to protect must-run rights? Draft strong PPA clauses, maintain robust SCADA and met station data, file claims promptly, and engage with industry associations for collective defence.

Related Glossary Terms

• Solar Curtailment
• Power Purchase Agreement
• Lithium Iron Phosphate
• Solar Bidding Types
• Wheeling Charges
• RPO
• Reverse Auction (Solar)
• DREBP

Related Resources

• PM Surya Ghar Complete Guide, Understand how residential solar fits within India’s broader renewable policy framework.
• Net Metering in India, Learn how net metering regulations complement must-run protections for distributed solar.
• OPEX vs CAPEX Solar, Financing structures that depend on must-run protection for revenue certainty.
• Residential Solar Systems, Home solar solutions from Gujarat’s #1 ranked PM Surya Ghar installer.
• Commercial Solar Solutions, C&I solar with performance guarantees backed by strong regulatory protections.
• Ground Mount Solar Parks, Utility-scale projects where must-run status is critical to project finance.
• Solar Calculator, Estimate savings and system size for your property.

Sources & References

• Electricity Act, 2003 (India)
• MNRE Notification on Must-Run Status for Renewable Energy, 2019
• CERC (Terms and Conditions for Tariff determination from Renewable Energy Sources) Regulations, 2020
• State Grid Codes (various states)
• APTEL Judgments on Must-Run and Deemed Generation
• National Electricity Policy, 2005
• Heaven Green Energy policy analysis and project documentation
• Gujarat Electricity Regulatory Commission (GERC) orders