1. Introduction

Priority dispatch for renewable energy refers to the legal and regulatory principle under which electricity generated from renewable sources such as solar, wind, wind-solar hybrid and certain hydro projects is given preferential treatment in scheduling and dispatch. The underlying idea is that renewable generation should ordinarily be evacuated and scheduled before conventional generation and should not be curtailed merely because another generator has a lower commercial cost or because of ordinary merit-order considerations.

In India, this principle is commonly expressed through the concept of “Must-Run” status. The legal framework has developed through the Electricity Act, 2003, the Central Electricity Regulatory Commission's grid regulations, the Electricity (Promotion of Generation of Electricity from Must-Run Power Plant) Rules, 2021, and subsequent grid-code provisions. (Press Information Bureau)

The current framework therefore seeks to balance two objectives:

maximising renewable-energy utilisation; and

maintaining electricity-grid security and reliability.

2. Meaning of Priority Dispatch

Traditional electricity systems frequently use merit-order dispatch. Generating stations are broadly scheduled according to their variable costs, subject to technical and system constraints.

Renewable generation creates a different regulatory problem. Solar and wind have:

zero or very low marginal fuel costs;

no conventional fuel requirement;

variable generation dependent upon weather;

significant capital expenditure;

environmental benefits;

renewable-purchase-policy significance.

Consequently, allowing renewable generators to be routinely backed down because a conventional generator is commercially preferable could undermine renewable-energy investment and statutory renewable-energy objectives.

Priority dispatch therefore means that renewable generation is ordinarily accepted and evacuated whenever technically feasible, with curtailment reserved principally for legitimate grid-security or technical reasons.

3. Statutory Foundation under the Electricity Act, 2003

The Electricity Act, 2003 provides the broader legal foundation for renewable-energy promotion.

Important provisions include:

Section 3

The Central Government is empowered to formulate the National Electricity Policy and Tariff Policy. These policies provide the framework for development of renewable energy and efficient electricity markets.

Section 61

While specifying tariff principles, the Appropriate Commission must take into account factors including the promotion of co-generation and generation of electricity from renewable sources.

Section 86(1)(e)

State Electricity Regulatory Commissions must promote:

co-generation;

generation of electricity from renewable sources;

electricity purchase from renewable sources through a suitable mechanism.

This provision is particularly important because priority dispatch is not an isolated commercial privilege; it forms part of the larger statutory policy of integrating renewable generation into the electricity system.

4. Electricity (Promotion of Generation of Electricity from Must-Run Power Plant) Rules, 2021

The most explicit national legal recognition of renewable priority dispatch came through the Electricity (Promotion of Generation of Electricity from Must-Run Power Plant) Rules, 2021. The Rules were notified under Section 176 of the Electricity Act. (Press Information Bureau)

Rule 3(1)

A:

wind power plant;

solar power plant;

wind-solar hybrid power plant;

hydro power plant, where excess water would otherwise lead to spillage;

or another notified renewable plant that has entered into an agreement to sell electricity is treated as a must-run power plant. (LegitQuest)

This is significant because it converts the concept of renewable priority dispatch from merely a regulatory preference into a formal legal rule.

5. Protection Against Commercial Curtailment

Rule 3 establishes an important principle: a must-run plant should not ordinarily be subjected to curtailment or regulation of generation or supply because of:

merit-order dispatch; or

other commercial considerations. (Press Information Bureau)

Therefore, a distribution licensee or system operator cannot ordinarily say:

“A conventional generator is commercially preferable, therefore the renewable generator should be backed down.”

The purpose is to prevent renewable generation from being displaced merely because another source is commercially more convenient.

6. Exception: Grid Security and Technical Constraints

Priority dispatch is not an absolute right to generate regardless of grid conditions.

The 2021 Rules recognise exceptions where curtailment is necessary because of:

technical constraints in the electricity grid; or

security of the electricity grid.

This distinction is fundamental.

Commercial curtailment

Generally impermissible merely because:

another generator is cheaper;

a conventional generator wants to operate;

the procurer prefers another source; or

ordinary merit-order considerations favour another plant.

Technical/security curtailment

Can be justified where necessary to protect:

grid stability;

transmission-system security;

equipment;

system frequency;

voltage stability;

personnel safety; or

other essential grid-security requirements.

Thus, priority dispatch operates within the boundaries of secure grid operation.

7. Compensation for Curtailment

The 2021 Rules also introduced an important economic protection.

Where supply from a must-run power plant is curtailed, compensation can become payable to the renewable generator at the rates specified in the relevant electricity purchase/supply agreement. The framework also provides for the renewable generator to sell curtailed electricity through a power exchange in specified circumstances where advance notice of curtailment is provided. (Press Information Bureau)

This is important because renewable projects generally involve substantial upfront investment. If the procurer could freely prevent generation after the project had been built, the economic assumptions underlying the PPA could be seriously affected.

8. Indian Electricity Grid Code and Priority Dispatch

The Indian Electricity Grid Code has historically provided specific protection for renewable generators.

Under the earlier IEGC 2010, Regulation 5.2(u) required the system operator to make efforts to evacuate available solar and wind power and treat them as must-run stations. Backing down could nevertheless be ordered where grid security or equipment/personnel safety was endangered.

Regulation 6.5(11) similarly treated specified renewable-energy plants as must-run and excluded them from ordinary merit-order dispatch. These provisions became central to several disputes before CERC. (CaseMine)

The IEGC Regulations, 2023 continue the regulatory recognition of renewable must-run treatment, while incorporating the contemporary requirements of system flexibility, storage and grid security. CERC's statement of reasons records stakeholder submissions concerning renewable must-run status and explains that the regulatory framework is intended to address curtailment while protecting system security. (CERC)

9. Role of Load Despatch Centres

Priority dispatch cannot operate without the cooperation of:

National Load Despatch Centre (NLDC);

Regional Load Despatch Centres (RLDCs);

State Load Despatch Centres (SLDCs).

These institutions perform real-time scheduling and dispatch functions.

An SLDC may therefore issue instructions to renewable generators, but such instructions must operate consistently with:

the Electricity Act;

applicable regulations;

the Grid Code;

must-run rules; and

legitimate grid-security requirements.

The existence of operational authority does not mean that the SLDC has unlimited discretion to curtail renewable generation.

10. Case Law: Wardha Solar (Maharashtra) Pvt. Ltd. v. KSLDC

One of the most important disputes concerning renewable priority dispatch is Wardha Solar (Maharashtra) Private Limited & Anr. v. Karnataka State Load Despatch Centre, CERC Petition No. 287/MP/2019.

The petition concerned alleged backing down of solar projects despite their must-run status. The petitioners sought:

enforcement of must-run status;

cessation of backing-down instructions;

recognition of deemed generation; and

compensation for generation allegedly lost because of curtailment. (CERC)

The case illustrates the central legal principle: renewable generators cannot ordinarily be backed down merely according to commercial merit order when applicable regulations classify them as must-run plants.

The case also demonstrates the importance of distinguishing lawful grid-security curtailment from ordinary commercial curtailment.

CERC ultimately dealt with the petition in an order dated 14 November 2023, after extensive proceedings. (CaseMine)

11. Prayatna Developers and Other Must-Run Proceedings

CERC's records show repeated proceedings involving enforcement of renewable must-run status.

For example, Prayatna Developers Private Limited brought a petition concerning enforcement of must-run status for a solar project and directions against backing-down instructions issued by the State Load Despatch Centre. (CERC)

These proceedings demonstrate that priority dispatch is not merely a theoretical policy principle. Renewable developers have repeatedly invoked the regulatory framework when they contend that renewable generation has been curtailed contrary to the Grid Code.

12. CERC Petition No. 204/MP/2020

Another important proceeding involved GRID Controller of India Limited/Southern Regional Load Despatch Centre and disputes concerning must-run status of solar and wind generators.

The proceeding invoked Regulation 5.2(u) and Regulation 6.5(11) of the IEGC 2010 and concerned directions to an SLDC regarding backing down of renewable generators. CERC records continue to identify this matter as involving enforcement of must-run status. (CERC)

The case demonstrates the institutional tension between:

renewable priority;

State-level operational control;

inter-State grid requirements; and

system-security considerations.

13. CERC Petition No. 147/MP/2021

In Petition No. 147/MP/2021, the Commission considered issues concerning renewable generation and grid operation. The record notes the position that renewable energy was to be treated as must-run and that increases in renewable generation should ordinarily be accommodated by reducing conventional generation while maintaining demand-generation balance. (CERC)

This illustrates the practical operation of priority dispatch: where renewable generation increases, conventional generation may need to be adjusted rather than automatically curtailing renewable generation.

However, this principle remains subject to system-security requirements.

14. Recent Regulatory Enforcement

The continuing relevance of the principle is evident from CERC proceedings in 2024–2026.

For example, CERC records show petitions concerning compensation for alleged unlawful curtailment of solar generation and enforcement of must-run status under:

the IEGC 2010;

the IEGC 2023;

the Must-Run Rules, 2021; and

Section 79 of the Electricity Act. (CERC)

Thus, priority dispatch remains an active regulatory issue rather than a settled historical doctrine.

15. Relationship with Renewable Purchase Obligations

Priority dispatch should be distinguished from Renewable Purchase Obligations (RPOs).

RPOs require obligated entities to purchase or consume specified quantities of renewable electricity.

Priority dispatch addresses a different question:

Once renewable electricity is available to the grid, should it be curtailed in favour of conventional generation?

The two principles complement one another.

RPOs stimulate renewable demand, while priority dispatch protects renewable generation from unnecessary curtailment.

The Supreme Court has also considered the statutory framework concerning renewable purchase obligations and renewable-energy regulations, demonstrating the broader legislative objective of promoting renewable electricity. (Sci API)

16. Priority Dispatch and Merit-Order Dispatch

The legal tension can be represented as follows:

17. Importance of Priority Dispatch

Priority dispatch serves several legal and economic objectives.

A. Renewable investment protection

Investors can make long-term investment decisions with greater certainty that contracted renewable generation will not be arbitrarily curtailed.

B. Climate policy

Priority dispatch supports India's broader transition toward lower-carbon electricity generation.

C. Reduction of fossil-fuel dependence

When renewable electricity is available, conventional generation can potentially be reduced, subject to technical constraints.

D. PPA stability

Unjustified curtailment may interfere with the commercial assumptions underlying long-term PPAs.

E. Regulatory certainty

Clear must-run rules reduce disputes concerning whether SLDCs can order renewable generators to back down.

18. Limitations of the Rule

Priority dispatch should not be misunderstood as an unconditional guarantee that every unit of renewable electricity will always be generated.

Important limitations include:

Grid security remains paramount.

Transmission congestion can necessitate curtailment.

Equipment or personnel safety may require backing down.

Renewable intermittency creates balancing requirements.

Storage and flexible generation may increasingly be used to accommodate renewable electricity.

Scheduling and forecasting requirements remain applicable.

The precise rights of a generator may depend upon its PPA, applicable Grid Code and regulatory jurisdiction.

The modern regulatory approach is therefore better described as “priority dispatch subject to grid security” rather than absolute dispatch priority.

19. Emerging Role of Battery Energy Storage

The increasing deployment of battery energy-storage systems changes the priority-dispatch debate.

Historically, renewable curtailment occurred partly because solar and wind generation could not always be shifted to another time.

Storage can:

absorb surplus solar generation;

shift electricity to evening demand;

reduce congestion;

provide ancillary services;

improve frequency regulation; and

reduce renewable curtailment.

Consequently, India's future dispatch framework is likely to combine renewable priority + flexible conventional generation + storage + better transmission planning.

20. Conclusion

Priority dispatch rules constitute a central component of India's renewable-energy regulatory framework. The legal principle has evolved from provisions in the Indian Electricity Grid Code into the more explicit Electricity (Promotion of Generation of Electricity from Must-Run Power Plant) Rules, 2021.

The basic rule is that qualifying renewable generators—particularly solar, wind, wind-solar hybrid and specified hydro plants—should ordinarily be treated as must-run and should not be curtailed merely because of merit-order economics or other commercial considerations. (Press Information Bureau)

At the same time, priority dispatch is not absolute. Grid security, technical constraints, equipment safety and system reliability can justify curtailment. The important legal question in a dispute is therefore whether the curtailment was genuinely required for a legitimate technical or security reason or was instead imposed for an impermissible commercial reason.

The Wardha Solar, Prayatna Developers, and subsequent CERC proceedings demonstrate the continuing importance of this distinction. (CaseMine)

Ultimately, India's priority-dispatch regime attempts to reconcile three objectives: renewable-energy promotion, contractual/investment certainty, and secure operation of the electricity grid. The future of the doctrine will increasingly depend on transmission expansion, storage, forecasting, flexible generation and sophisticated system-operation rules.