UC BERKELEY FIRM CLEAN POWER RESEARCH
Solar and batteries can run like a thermal plant, at less than the price of new coal power
An analysis of India’s landmark 1,000 MW “thermal mimic” auction finds that about 3 GW of solar and 12 GWh of batteries per 1,000 MW contracted can serve the tender’s round-the-clock profile at ₹5.15 per kWh — inside the ₹5.25 discovered tariff, and below recent thermal power purchase agreements of ₹5.4 to 6.3.
SECI’s delivery floor across one day: at least 90% of contracted capacity through six night-and-morning peak hours, 50–60% through solar hours, 70% elsewhere — with the simulated output of the least-cost plant meeting it.
UC BERKELEY ANALYSIS · AUGUST 2026
THE AUCTION, SIMULATED
ALL-IN DELIVERED COST
₹5.15/kWh
₹0.10 inside the discovered tariff of SECI's auction, from 3.0 GW-AC of solar and 12 GWh of usable storage per 1,000 MW.
RAJASTHAN · WEATHER YEARS 2015–2024
HOURS MET OUTRIGHT
94%
94% of all hours clear the floor outright in a typical weather year; the tender's 5% green-market allowance covers nearly all of the rest.
RAJASTHAN LEAST-COST DESIGN · TYPICAL YEAR
COAL, UNDER ITS OWN TEST
48%
48% of India's 213 coal stations would have paid penalties under this tender's rules, scored on their actual outage records.
CEA DAILY OUTAGE DATA · JUN 2024 – MAY 2025
A thermal mimic is a renewable plant contracted to deliver a thermal plant’s operating profile — block by block, every day, for 25 years.
STUDIES
Three separate studies, three different questions. The tender analysis prices SECI’s shaped “thermal mimic” contract — 3 GW of solar and 12 GWh of storage per 1,000 MW, at ₹5.15/kWh. The two working papers ask a different question with a different plant: whether solar-plus-storage can replace coal outright — one 5 GW + 16 GWh plant holding a flat 1 GW (Part 1), and 120 such plants holding 100 GW across the country (Part 2). Configurations and costs differ by design; all three run on weather years 2015–2024.
Inside SECI's ₹5.25 thermal-mimic auction
Can solar and batteries serve the FDRE-RTC-V profile at the discovered tariff? Hourly simulation of the final rules — the least-cost design, its penalty exposure, and what the result implies for battery prices.
₹5.15/kWh all-in cost94% hours met outright10×10 states × weather years
A single plant can match a coal plant's availability
A 5 GW solar + 16 GWh storage configuration behind one grid connection clears the CERC coal availability norms in every state and every weather year simulated — at a plant-gate LCOE below the new-coal PPA range.
90.7% median availability85% coal norm₹5.08/kWh plant-gate LCOE
A fleet of such plants can match the coal fleet
120 plants across 18 states, dispatched as a portfolio: geographic diversification turns plant-level weather failures into shallow fleet-level dips, the same mechanism that makes coal fleets reliable.
99.2–100% fleet reliability120 plants · 18 states600 GW solar · 2,134 GWh storage
PRESS
The press release, the full deck, and every chart in print resolution are available for reporting. Read the release and media kit →