ENERGY LAW AND ECONOMIC DISPATCH OF RENEWABLE RESOURCES

1. Introduction

Economic dispatch of renewable resources concerns the legal and regulatory rules governing how electricity system operators select and schedule available generation to meet demand at the lowest reasonable system cost while maintaining reliability. Traditional economic dispatch follows the merit-order principle, under which generating units with lower short-run marginal costs are generally dispatched before more expensive units.

Renewable resources such as wind and solar create distinctive issues because their fuel cost is effectively zero, their output is weather-dependent, and many regulatory systems accord them preferential or must-run status. Energy law therefore has to reconcile cost-efficient dispatch with renewable-policy objectives, congestion management, balancing requirements, transmission limits, storage operation, and system security.

2. Merit Order and Renewable Generation

In conventional markets, economic dispatch compares the variable costs of available generators. Because solar and wind have very low marginal operating costs, they normally enter the merit order ahead of fossil-fuel generation.

However, renewable dispatch is not determined by economics alone. Grid operators must also account for:

transmission congestion;

minimum stable generation limits of thermal plants;

reserve requirements;

frequency and voltage security;

ramping capability;

forecasting error; and

transmission availability.

Consequently, even low-cost renewable generation may sometimes need to be curtailed for genuine technical reasons.

3. Must-Run Status and Curtailment

Indian regulation has historically granted must-run treatment to many renewable generators. The purpose is to prevent arbitrary backing down of renewable projects merely because conventional generation is commercially cheaper to keep online or because of contractual convenience.

CERC proceedings continue to address alleged violations of this principle. In 2025 and 2026, petitions were pending concerning solar generators seeking enforcement of must-run status and compensation for generation losses caused by alleged unlawful curtailment or inadequate transmission facilities.

The Electricity (Promotion of Generation of Electricity from Must-Run Power Plant) Rules, 2021 also form part of the current legal framework invoked in such proceedings.

Thus, economic dispatch cannot automatically justify backing down renewable generation where binding grid-code or must-run rules limit curtailment.

4. Storage and Firm Renewable Dispatch

The traditional distinction between variable renewables and dispatchable generation is becoming less rigid because battery storage can shift renewable electricity across time.

India is increasingly procuring firm and dispatchable renewable energy combined with energy-storage systems. CERC records show tariff-adoption proceedings for firm and dispatchable renewable projects using storage, demonstrating the movement toward renewable resources capable of satisfying specified delivery profiles rather than merely producing when weather conditions permit.

This changes economic dispatch because renewable-plus-storage projects may provide peak energy, reserves, ramping support, and dispatchable capacity.

5. Curtailment, Compensation and Grid Discipline

A lawful dispatch framework must distinguish between technical curtailment and commercial curtailment.

Technical curtailment may be justified where necessary to prevent grid instability, manage congestion, or respond to emergencies. Commercial curtailment merely to favor another generator may conflict with applicable must-run requirements.

Recent CERC matters include claims for compensation where renewable generators allege backing-down instructions caused generation loss.

At the same time, renewable generators remain subject to scheduling and grid-discipline requirements. Preferential dispatch does not create an unrestricted right to inject electricity regardless of system conditions.

6. Case Law

FERC v Electric Power Supply Association, 577 U.S. 260 (2016)

Facts: FERC established rules allowing demand-response resources to compete with generation in organized wholesale electricity markets.

Legal Issue: Whether FERC could regulate compensation for resources that alter electricity demand rather than physically generate electricity.

Judgment: The United States Supreme Court upheld FERC's rule.

Legal Principle/Ratio: Wholesale-market regulation may recognize technologically different resources where their actions directly affect wholesale rates and market operation.

Significance: The case supports technology-neutral economic dispatch in which renewables, storage, and demand response can compete according to the services they provide rather than traditional generator classifications.

Wardha Solar (Maharashtra) Pvt Ltd & Anr., Petition No. 287/MP/2019, CERC

Facts: Solar generators challenged backing-down instructions and sought enforcement of their must-run status under the Indian Electricity Grid Code.

Legal Issue: Whether renewable generators could be curtailed contrary to must-run requirements except where justified by genuine grid-security considerations.

Judgment: The dispute formed part of CERC proceedings concerning enforcement of must-run protections and renewable curtailment.

Legal Principle/Ratio: Renewable curtailment must comply with the governing grid-code framework and cannot be treated as an unrestricted commercial dispatch choice.

Significance: The proceedings illustrate the legal limits placed upon purely economic dispatch where renewable-support rules create preferential scheduling rights.

7. Conclusion

Economic dispatch of renewable resources requires coordination between merit-order economics, must-run protections, forecasting, congestion management, balancing, storage, reliability, and compensation rules. Modern energy law increasingly seeks to dispatch the lowest-cost and cleanest available resources while preserving system security. The central legal challenge is ensuring that renewable curtailment occurs only for legitimate operational reasons and through transparent, enforceable rules rather than arbitrary commercial preference.