Coal fleet’s changing role in the power system

India's coal fleet is shifting from baseload to flexible balancing to integrate rising solar and wind energy. By FY 2031–32, coal plants will need to operate closer to their technical minimums, with a projected average plant load factor (PLF) drop from 69% to 55%. This transition will disproportionately impact high-cost, less efficient units, suggesting that the 35 GW of coal capacity currently under construction is sufficient for supply security without further additions.

• The role of coal generation is shifting from steady baseload to flexible balancing resources, requiring deeper mid-day turndowns and faster evening ramp-ups to accommodate variable renewable energy.
• The 2023 Grid Code formalises the Minimum Thermal Load (MTL)—the lowest reliable output level—at 55% of rated capacity, with ramping expectations of approximately 1% of rated capacity per minute.
• Modelling for FY 2031–32 indicates a significant daily swing in coal output, peaking at approximately 190 GW during non-solar hours and ramping down to roughly 112 GW at midday solar peaks.
• To avoid solar curtailment and expensive gas-based generation, many plants may need to operate at an effective MTL of around 40%, which is lower than the current 55% standard.
• Flexibility burdens currently fall disproportionately on a few Inter-State Generating Station (ISGS) plants, while intra-state generators remain largely unresponsive to flexibility needs.
• Average plant load factors (PLF) for the coal fleet are projected to decline from approximately 69% in FY 2024–25 to 55% by FY 2031–32.
• The reduction in utilisation will be non-uniform, with plants having variable costs higher than roughly INR 2.8/kWh seeing significant reductions in run hours.
• India does not require new coal capacity beyond the 35 GW currently under construction to maintain supply-side security through FY 2031–32.

APA

Ember (2025). Coal fleet’s changing role in the power system. https://ember-energy.org/chapter/coal-fleets-changing-role-in-the-power-system/

Chicago

Ember. Coal fleet’s changing role in the power system. 2025. https://ember-energy.org/chapter/coal-fleets-changing-role-in-the-power-system/.

Wikipedia

{{cite report |author=Ember |title=Coal fleet’s changing role in the power system |date=29 October 2025 |url=https://ember-energy.org/chapter/coal-fleets-changing-role-in-the-power-system/ |access-date=17 August 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{ember2025coal, author = {{Ember}}, title = {{Coal fleet’s changing role in the power system}}, institution = {Ember}, year = {2025}, month = oct, url = {https://ember-energy.org/chapter/coal-fleets-changing-role-in-the-power-system/}, urldate = {2026-08-17}, note = {Indexed by Climate Insights Directory} }