Pinnapuram IREP Case Study: India's World-First Integrated Renewable Energy Project Driving Dispatchable Power & Grid Stability

Executive Summary

Pinnapuram IREP — India's first Integrated Renewable Energy Project — stands as the world's largest gigawatt-scale facility to combine solar, wind, and pumped-storage hydropower under one roof, finally delivering what the energy industry calls Dispatchable Renewable Energy: clean power on demand, not just when the sun shines.

Developed by Greenko Group in Kurnool District, Andhra Pradesh, this project has a total installed capacity of 5,230 MW — built up as 3,000–4,000 MW of solar, 550–1,000 MW of wind, and 1,680 MW of closed-loop pumped storage hydropower. Total investment stands at USD 4.2 billion (approximately ₹35,000 Crore). A landmark milestone was reached in October 2024 when Unit #1 of the pumped storage system completed wet commissioning.

For decades, the biggest obstacle to replacing fossil fuels with renewables has been intermittency — the sun does not shine at night, and wind speeds are unpredictable.

Pinnapuram directly solves this by storing surplus solar and wind energy as gravitational potential energy in water, then releasing it on demand. This ability — called Schedulable Power On Demand (SPOD) — is what makes Pinnapuram a genuine global benchmark.

Project at a Glancee

Parameter	Details
Developer	Greenko Group (Greenko AP01 IREP Pvt. Ltd.)
Location	Pinnapuram, Kurnool District, Andhra Pradesh, India
Solar Capacity	3,000–4,000 MW (phased buildout)
Wind Capacity	550–1,000 MW
Pumped Storage	1,680 MW / 10,080 MWh per day (single cycle)
Total Investment	USD 4.2 Billion (~₹35,000 Crore)
CO₂ Avoided	~15 million tonnes per annum
Land Area	714 Ha (including 380 Ha forest land)
Water Allocation	1.3 TMC from Gorakallu Reservoir (non-consumptive)
Key Milestone	Unit #1 wet commissioning — October 2024
Principal Designer	AFRY India (subsidiary of Swedish engineering firm AFRY)
Key Offtaker	SECI (900 MW, long-term contract)

Introduction — Pinnapuram IREP in Context

India's energy story is one of sharp contradiction. The country has some of the world's best solar irradiation levels — averaging 5–7 kWh per square metre per day — and ranks among the top five nations for installed renewable capacity. Yet every evening, as the sun sets, its massive solar fleet goes silent. The national grid has historically relied on coal-fired plants to fill that gap.

India's peak electricity demand regularly crosses 220 GW, climbing each year as air conditioning, electric vehicles, and industrial activity expand.

The Ministry of New and Renewable Energy (MNRE) has set a target of 500 GW of non-fossil fuel capacity by 2030. Meeting that target requires not just installing solar panels — it means making that solar power available at 6 PM when demand peaks, not at noon when the grid already has surplus power. This structural problem is exactly what Pinnapuram solves.

The project began with a Memorandum of Understanding (MoU) signed between Greenko Energies Private Limited and the Government of Andhra Pradesh in February 2018.

Detailed design contracts were awarded to AFRY India in March 2020. Construction formally commenced in May 2022 when Andhra Pradesh Chief Minister YS Jagan Mohan Reddy performed the first concrete pour.

India's Union Minister for New and Renewable Energy, Pralhad Joshi, personally visited the site in April 2025, calling it

"a shining example of India's green energy potential."

What is Pinnapuram IREP? — Definition and Core Components

Pinnapuram IREP is a first-of-its-kind hybrid energy system that brings together three complementary renewable technologies under a single management platform to produce firm, round-the-clock green electricity.

Unlike traditional power projects that rely on one energy source, the IREP uses solar energy during the day, wind energy around the clock, and a water-based storage system to fill the gaps — at a scale the world has never attempted at a single location.

The Three Pillars of Pinnapuram

• Solar Power (up to 3,000–4,000 MW): Large photovoltaic (PV) arrays across Kurnool District's arid terrain capture sunlight during daylight hours. The solar panels feed electricity directly into the grid and simultaneously power the water-pumping system during off-peak hours.

• Wind Power (550–1,000 MW): Wind turbines provide generation during non-daylight hours and during cloud cover, complementing solar. Their combined output ensures the storage system receives near-continuous electricity for pumping operations.

• Closed-Loop Pumped Storage Hydropower (1,680 MW / 10,080 MWh per day): Two newly constructed reservoirs — one at a higher elevation, one below — act as a giant rechargeable battery. Water is pumped uphill using surplus solar/wind power and flows downhill through turbines to generate electricity on demand.

Technical Deep Dive: The Closed-Loop System

The pumped storage component uses a closed-loop, off-stream design. Neither reservoir is connected to a natural river flow — a deliberate design choice that avoids the ecological disruption of traditional dams, reduces flooding risk, and gives operators full control over water levels.

The upper reservoir is constructed across Muni Madugu with a dam height of 35 metres and a storage capacity of 1 TMC (thousand million cubic feet). The lower reservoir reaches a maximum height of 33 metres, with matching storage.

Both are enclosed by 9.6 km-long rockfill embankments. Water was sourced once from the existing Gorakallu Reservoir, with 1.3 TMC allocated on a non-consumptive basis by the Andhra Pradesh government.

The powerhouse contains eight reverse-Francis turbines — six units of 240 MW each and two units of 120 MW each — supplied by Austrian engineering company Andritz. In pump mode, the system uses approximately 1,140 MW to push 1 TMC of water uphill in about 9.2 hours. In generation mode, water flows back through turbines at 862.5 cubic metres per second (Cumec), producing clean peak electricity.

Pinnapuram IREP vs. Standard Solar + Li-Ion Battery

Feature	Pinnapuram IREP (Pumped Storage)	Standard Solar + Li-Ion Battery
Storage Duration	10–16 hours per cycle	2–4 hours per cycle
System Lifespan	50–100 years	10–15 years
Cost per MWh (long-term)	Lower at scale (gravity-based)	Higher (battery replacement cycles)
Environmental Risk	Water evaporation, land use	Mining, chemical waste disposal
Scalability	Highly scalable (geography-dependent)	Scalable but capital-intensive
Round-Trip Efficiency	~75–80%	~85–90%

Why Pinnapuram IREP Matters — Dispatchable & Schedulable Renewable Power

Key Definition: "Dispatchable Renewable Energy" is clean electricity that grid operators can call upon exactly when needed — not just when weather permits. Pinnapuram is India's first project to deliver this at gigawatt scale.

Schedulable Power On Demand (SPOD) means grid operators can tell the Pinnapuram facility exactly how much power they need and exactly when — say, 800 MW starting at 6:30 PM for four hours — and the project delivers precisely that, on schedule.

This makes it functionally equivalent to a coal power plant, but without any carbon emissions, fuel costs, or combustion pollution.

How the Energy Flow Works — Step by Step

1 Daytime Surplus: Solar panels generate peak power from roughly 8 AM to 4 PM. During this window, electricity demand is often lower than solar output. The surplus powers the pumps.

2 Water Pumped Uphill: Using ~1,140 MW of electricity, water transfers from the lower to the upper reservoir — storing gravitational potential energy silently and at scale.

3 Evening Peak Demand: As solar generation drops after sunset, electricity demand surges for cooking, lighting, and industry. The upper reservoir's gates open.

4 Turbines Generate: Water flows downhill, spinning the reverse-Francis turbines at full capacity. Up to 1,680 MW of clean electricity enters the grid precisely when needed.

5 Cycle Repeats: The system resets overnight, ready for the next day's solar cycle. At 10,080 MWh per cycle, the project can supply millions of homes for an entire evening.

"India's national grid now has its first true renewable alternative to coal-fired peaking power — and it can be scheduled like a utility appointment."

Grid Stability: India's Renewable Shock Absorber

India's national grid manages one of the most complex balancing acts in the world — coordinating power across 33 states and union territories with wildly varying demand patterns and an increasing share of variable renewables. Frequency deviations (above or below 50 Hz) can cause widespread outages.

Pinnapuram IREP acts as a grid-scale frequency regulator: when there is surplus power, it absorbs it by pumping; when there is a shortfall, it injects electricity within minutes.

The Central Electricity Authority (CEA) projects India's pumped storage capacity must grow from 4.7 GW to 90 GW by 2047. Pinnapuram is the trailblazer.

Methodology — Research Approach to This Case Study

This case study is based on a rigorous review of primary and secondary sources: government environmental clearance filings from India's Ministry of Environment, Forest and Climate Change (MoEFCC); technical project data from Greenko Group's official project page; engineering reports from principal design consultant AFRY India; news from Power Technology, NS Energy Business, PV Magazine India, and International Water Power Magazine; policy documents from the Central Electricity Authority (CEA); and the official Government of India Press Information Bureau (PIB) release from Minister Pralhad Joshi's April 2025 site visit.

Key Metrics Evaluated

• Generation Capacity: Installed MW across solar, wind, and pumped storage phases

• Storage Duration: Hours of dispatchable energy per generation cycle (10+ hours)

• Financial Structure: Capital expenditure, green bond financing, equity ownership

• Carbon Metrics: Annual CO₂ equivalent avoided vs. a coal-fired baseline

• Policy Compliance: AP Renewable Energy Export Policy, CEA approvals, Make in India

• Environmental & Social Indicators: Land use, water usage, forest impact, employment

Technical Analysis — Engineering the World's Largest IREP

The engineering complexity of Pinnapuram IREP is unlike any previously attempted project in India. Coordinating solar, wind, and hydro within a single dispatch platform while maintaining grid frequency requires advanced digital infrastructure alongside physical construction excellence.

Reservoir Engineering

Both reservoirs were built in existing natural depressions in Kurnool's landscape, minimising excavation and earthwork. The lower reservoir has a maximum embankment height of 33 metres and the upper reaches 35 metres, with average heights of 12–14 metres across both structures, totalling 9.6 km of rockfill dam wall.

The choice of rockfill embankment with an Asphalt Surface Sealing System (ASSS) is technically significant. Unlike concrete-faced dams, ASSS rockfill construction is faster, more cost-effective, and tolerant of seismic conditions common to the Deccan Plateau. The asphalt layer prevents water seepage and reduces evaporation — critical in Kurnool's semi-arid climate.

The Pump-Generate Cycle: Efficiency and Output

A round-trip efficiency of approximately 75–80% means that for every 100 units of renewable electricity used to pump water uphill, the system recovers 75–80 units during generation. While lower than lithium-ion batteries (85–90%), the 10–16 hour discharge duration and 50-year-plus operational lifespan make pumped storage far more economical at gigawatt scale over the project's full lifetime.

The power station connects to the national grid via two 400 kV double-circuit transmission lines: one 20 km line to Power Grid Corporation of India's (PGCIL) 765/400 kV substation at Orvakallu, and a second 6 km line to Pinnapuram's Central Pooling Station (CPS), which aggregates power from all three generation sources before dispatch.

Intelligent Energy Management

Greenko operates a Renewable Energy Management Centre (REMC) and an Intelligent Energy Platform for this project. These digital systems monitor real-time generation from solar and wind assets, forecast output up to 72 hours ahead, and automatically trigger pumping or generation cycles. This digital layer is what makes SPOD commercially dependable.

Policy & Regulatory Framework

Pinnapuram IREP operates within a supportive but layered policy environment. The Andhra Pradesh Renewable Energy Export Policy provides a structured framework for private developers to set up renewable projects and sell power both within and outside the state. This inter-state sales model is critical — Pinnapuram's primary offtake covers states across India, not just Andhra Pradesh.

The Government of Andhra Pradesh allotted 4,766.28 acres of land to Greenko at market value. A Green Energy Development Charge of ₹1,00,000 (~USD 1,327) per MW per year was levied for the first 25 years for the pumped storage component, and the same rate for 28 years for solar and wind — ensuring the state earns long-term fiscal returns.

The Central Electricity Authority (CEA) provided technical clearances, while environmental clearances were obtained from MoEFCC following an EIA prepared by RS Envirolink Technologies. The feasibility study was conducted by Aarvee Associates Architects Engineers and Consultants.

On the Make in India front, while key electromechanical equipment (reverse-Francis turbines) was sourced from Andritz (Austria) due to specialised engineering requirements, civil works, rockfill material, asphalt surface sealing, and local logistics involved a substantial domestic supply chain. The Andhra Pradesh government sees this project as a catalyst for regional ancillary industry development.

Economic & Financial Analysis

The total capital outlay for Pinnapuram IREP is USD 4.2 billion (~₹35,000 Crore). Of this, USD 1.2 billion is for pumped storage hydropower and the remaining USD 3 billion covers solar and wind infrastructure — making it one of the single largest private renewable investments in India's history.

Financing Structure

Financing Source	Type	Details
GIC (Singapore)	Equity	52% ownership in Greenko
ADIA (Abu Dhabi)	Equity	14% ownership in Greenko
ORIX Corp. (Japan)	Equity	22% ownership in Greenko
Green Bonds (Project)	Debt	USD 750 million raised specifically for IREP
Total Green Bonds (Greenko)	Debt	USD 5+ billion raised cumulatively
IREDA / PFC / REC	Long-term Loans	20–25 year concessional loans for PSP

Greenko is among India's largest green bond issuers, having raised USD 950 million in a single green bond issuance in July 2019 — the largest from Asia at that time, oversubscribed more than three times. Across its history, the company has raised over USD 10 billion total: USD 2.5 billion in equity and over USD 5 billion in green bond debt.

Tariff Competitiveness

In January 2020, Greenko won a Solar Energy Corporation of India (SECI) competitive auction for 900 MW of round-the-clock (RTC) renewable power at a peak tariff of ₹6.12 per kWh. While higher than simple solar tariffs (₹2.0–2.5/kWh), this is significantly lower than gas turbine or diesel peaking power, which can exceed ₹8–12/kWh. Key long-term offtakers include SECI (900 MW) and ArcelorMittal Nippon Steel India.

Environmental & Social Impacts

Pinnapuram IREP is projected to avoid approximately 15 million tonnes of CO₂ equivalent per annum relative to a coal-fired power baseline, calculated on India's average grid emission intensity of approximately 0.71 kg CO₂ per kWh. Across a 25-year project life, cumulative climate benefit exceeds 375 million tonnes of CO₂.

Land Use and Forest Management

The project uses 714 hectares (~1,764 acres), of which 380 hectares is classified as forest land under Gani Forest, Kurnool Range. Environmental clearances required Greenko to submit plans for Catchment Area Treatment, Compensatory Afforestation, and rehabilitation measures. The closed-loop reservoir design avoids disrupting downstream river ecosystems — a significant advantage over conventional dams.

Water Usage

The project makes non-consumptive use of 1.3 TMC of water from the Gorakallu Reservoir. The water is not depleted — it circulates between the two reservoirs indefinitely. Only minor evaporation losses need periodic replenishment. This is critical in Kurnool, which is a semi-arid region that faces periodic drought.

Employment and Regional Development

Construction at this scale typically generates 5,000–10,000 direct construction jobs over 3–4 years, with a multiplier effect on local services.

During operations, the project creates several hundred permanent skilled positions for engineers, technicians, and plant operators. Greenko CEO Anil Chalamalasetty confirmed the project will "catalyze strong economic growth in the region and aid development of ancillary industries."

Comparative Perspective — Pinnapuram Against Global Benchmarks

Pinnapuram's defining characteristic is not just storage capacity, but the integration of all three renewable technologies at gigawatt scale at a single location.

Most global projects do one of these things — not all three, simultaneously.

Project	Country	Capacity	Technology	Key Differentiator
Pinnapuram IREP	India	5,230 MW+	Solar + Wind + Pumped Storage	World's first tri-tech IREP at single location
Snowy 2.0	Australia	2,000 MW	Pumped Storage only	Longest PSP tunnels in Southern Hemisphere
Fengning PSP	China	3,600 MW	Pumped Storage only	Largest PSP globally by power output
Gujarat HREP	India	30,000 MW	Solar + Wind + H₂	Larger planned capacity; no PSP integration
Nant de Drance	Switzerland	900 MW	Pumped Storage only	High-altitude Alpine PSP, no solar/wind

Challenges & Lessons Learned

No project of this scale is built without difficulty. Pinnapuram's development — from the 2018 MoU to 2024's first unit commissioning — took six years and surfaced engineering, supply chain, and environmental challenges that future developers must prepare for.

Engineering: Coordinating Three Technologies

Integrating solar, wind, and pumped storage under a single dispatch platform has no established global template. Greenko and AFRY India had to develop new grid balancing algorithms, control software, and interface protocols between electromechanical hydro systems and solar inverters.

Managing the transition from pump mode to generate mode within reverse-Francis turbines required extensive commissioning trials — as evidenced by the October 2024 wet commissioning milestone coming after the original 2023 commercial operation target.

Supply Chain: Material Sourcing and Logistics

Specialised electromechanical equipment — the eight reverse-Francis turbines from Andritz — had to be transported to a site located 60 km from Kurnool and 81 km from the nearest rail head, requiring dedicated road upgrades and heavy-haulage logistics.

Supply chain disruptions during 2021–2022 (COVID-19 aftermath and global freight challenges) affected timelines.

Environmental: Water Stress and Forest Land

Kurnool is periodically water-stressed. Public concerns about water resource allocation in a dryland agricultural district required transparent regulatory assurance.

The use of 380 hectares of forest land required compensatory afforestation under the Forest Conservation Act, adding time and cost to the clearance process. Future projects in similar geographies must build local stakeholder engagement and robust environmental monitoring into timelines from day one.

Future Outlook — Scaling the IREP Model

Pinnapuram is not Greenko's endpoint — it is the starting point. The company's publicly stated ambition is to build a 100+ GWh per day energy storage cloud platform across India using the Pinnapuram model as the template, creating a national network of dispatchable renewable energy hubs managed digitally.

Contribution to India's 500 GW Target by 2030

India's National Electricity Plan (NEP 2023) maps a path to 500 GW of non-fossil capacity by 2030. Simple solar and wind additions can get the country most of the way there in installed capacity — but making that capacity firm and dispatchable requires massive storage investment.

The CEA's projection of 90 GW of pumped storage by 2047 requires dozens of Pinnapuram-scale projects. Pinnapuram proves that the engineering, financing, and regulatory pathways are all viable within the Indian context.

Green Hydrogen: The Next Frontier

Green hydrogen — produced by splitting water using 100% renewable electricity via electrolysis — requires round-the-clock, low-cost clean power to be economically viable. A facility like Pinnapuram, capable of supplying schedulable green power at ₹6.12/kWh, is well-positioned to power dedicated green hydrogen and green ammonia production — exactly what Greenko's offtake strategy has already factored in.

India's National Green Hydrogen Mission, with a budget of ₹19,744 Crore (USD 2.3 billion), targets 5 million metric tonnes of green hydrogen by 2030, requiring approximately 125 GW of dedicated renewable power. Projects like Pinnapuram are the foundational infrastructure for that industrial future.

Conclusion — A Blueprint the World Can Follow

Pinnapuram IREP is proof of concept for an entirely new category of energy infrastructure — one that solves the oldest problem in renewable energy: how do you deliver clean power when the customer needs it, not just when the weather allows?

In delivering 10,080 MWh of clean, dispatchable energy per day — backed by up to 4,000 MW of solar, 1,000 MW of wind, and 1,680 MW of closed-loop pumped storage — at a total investment of USD 4.2 billion, Greenko has demonstrated that commercial-scale dispatchable renewable energy is financially viable, technically achievable, and grid-compatible, even within the regulatory and geographic complexities of a developing nation.

The project avoids an estimated 15 million tonnes of CO₂ per annum, supports regional employment, advances green hydrogen readiness, and provides the Indian national grid with its first genuine renewable alternative to coal-fired peaking power.

Is the Pinnapuram model replicable? Yes — for countries with the right topography, water access, renewable resources, and policy frameworks. Thanks to this project, those countries now also have the blueprint.

FAQs — Pinnapuram IREP

Q1: What makes Pinnapuram IREP unique compared to other renewable projects?

Pinnapuram IREP is the world's first project to combine solar, wind, and closed-loop pumped storage hydropower at gigawatt scale at a single location, delivering fully schedulable, dispatchable clean energy. Unlike conventional solar farms or standalone pumped storage, it can supply firm renewable power on demand — 24 hours a day — making it functionally equivalent to a thermal power plant without any carbon emissions.

Q2: How does pumped storage hydro work in the context of IREP?

Pumped storage works like a giant rechargeable water battery. Surplus solar/wind electricity powers pumps that move water from a lower reservoir to a higher one. When demand spikes, water flows back down through turbines to produce electricity. At Pinnapuram, this generates up to 1,680 MW for approximately 6 hours per cycle, with a total daily storage capacity of 10,080 MWh.

Q3: What is Scheduled Power On Demand (SPOD) and why is it important?

SPOD stands for Schedulable Power On Demand — the ability to pre-commit to a specific volume of electricity delivery at a precise time. This lets renewable energy compete directly with fossil fuel plants for firm power contracts, a market essential for enabling coal plant retirement and industrial decarbonisation. Without SPOD, renewable energy remains secondary to dispatchable fossil generation.

Q4: How much carbon emission reduction can IREP achieve?

Pinnapuram IREP is projected to avoid approximately 15 million tonnes of CO₂ equivalent per annum relative to a coal-fired power baseline. Based on India's grid emission intensity factor, over a 25-year operational life, total cumulative avoidance exceeds 375 million tonnes of CO₂ — equivalent to taking tens of millions of petrol cars off the road permanently.

Q5: When is Pinnapuram IREP expected to be fully operational?

The pumped storage component achieved a major milestone when Unit #1 completed wet commissioning in October 2024. The project was originally targeted for Q4 2023 but faced delays typical of large-scale infrastructure. Full commercial operation for all 1,680 MW of pumped storage, together with the complete solar and wind arrays, is expected on a phased basis through 2025–2026.

Q6: What are the environmental concerns associated with the project?

Primary environmental concerns include use of 380 hectares of forest land requiring compensatory afforestation; water evaporation from open reservoirs in Kurnool's semi-arid climate; and biodiversity impacts on local ecosystems. Greenko has addressed these through an Environmental Impact Assessment by RS Envirolink Technologies, afforestation plans, and the inherently water-efficient closed-loop design.

Disclaimer:

The information in this article is published for general informational and educational purposes only. GreenFuelJournal.com does not provide financial, investment, or legal advice. All data, statistics, and project details are sourced from publicly available information at the time of publication and may be subject to change. Readers are advised to verify all figures independently and consult qualified professionals before making any investment or business decisions. GreenFuelJournal.com is not affiliated with Greenko Group or any of its subsidiaries.

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References & Citations

This article is backed by authoritative sources and research. All references were verified and cross-checked at the time of writing.

[R1] Greenko Group — Official Pinnapuram IREP Project Page: greenkogroup.com/ap01.php

[R2] Power Technology — Pinnapuram Integrated Renewable Energy Project, India: power-technology.com

[R3] NS Energy Business — Pinnapuram IRESP, India: nsenergybusiness.com

[R4] AFRY India — Pinnapuram IRESP Project Profile: afry.com

[R5] Press Information Bureau (PIB), Government of India — Pralhad Joshi Visit, April 2025: pib.gov.in

[R6] International Water Power Magazine — Unit #1 Wet Commissioning, October 2024: waterpowermagazine.com

[R7] Mercom India — AP Government Approves Greenko Solar, Wind & Storage, June 2020: mercomindia.com

[R8] PV Magazine India — Greenko $4.2 Billion IREP, April 2025: pv-magazine-india.com

[R9] Power Line Magazine — Addressing Intermittency: Greenko's IREP, August 2025: powerline.net.in

[R10] NS Energy Business — Greenko begins construction, May 2022: nsenergybusiness.com

[R11] Renewable Watch — Greenko IRESPs Overview: renewablewatch.in

[R12] PV Magazine India — Deputy CM visits Greenko IREP, January 2025: pv-magazine-india.com

[R13] Central Electricity Authority — National Electricity Plan 2023: cea.nic.in

[R14] Ministry of New and Renewable Energy — National Green Hydrogen Mission: mnre.gov.in

© Green Fuel Journal Research Division | Published: February 2026