India's 42 GW of Unsold Solar Turns to Batteries for a Buyer
India's renewable energy secretary says 42 GW of solar capacity is still hunting for buyers, and the 18 GW without batteries faces the hardest road. Developers are responding by adding storage.
Santosh Sarangi, Secretary of India's Ministry of New and Renewable Energy, said on Friday at the BNEF Summit in New Delhi that 42 GW of Indian solar projects still lack offtakers, with roughly 18 GW of solar-only capacity without batteries most at risk, prompting developers to bolt storage onto photovoltaic projects to attract buyers and cut curtailment.
India has built solar farms faster than it has built customers for them. On Friday, Santosh Sarangi, Secretary of the Ministry of New and Renewable Energy, put a number on the mismatch: as much as 42 gigawatts of solar capacity is still looking for an offtaker — a buyer willing to sign a long-term power purchase agreement. Of that, roughly 18 GW consists of solar-only projects with no battery attached, and those, Sarangi said, are the ones most likely to keep struggling.
Speaking at the BNEF Summit in New Delhi, Sarangi said developers have started bolting battery storage onto photovoltaic projects specifically to make them saleable and to reduce curtailment — the share of generated electricity that grids simply cannot absorb and therefore instruct plants to stop producing. The remarks were reported by OilPrice.
Why a solar-only project has become hard to sell
The economics of Indian solar have been inverted by their own success. A plant that delivers its entire output in a bunched midday window is competing against every other plant doing exactly the same thing at exactly the same hour. Distribution companies — the state-owned discoms that are the ultimate buyers of most Indian renewable power — have all the midday electrons they can use. What they are short of is power at dusk, when air-conditioning load peaks and solar output collapses.
That is the practical meaning of the 18 GW figure. It is not that those projects are badly built or badly located. It is that their product arrives at the wrong time of day, and a discom signing a 25-year contract has to live with the consequences of that mismatch for a quarter of a century. Curtailment is the visible symptom: energy generated, energy paid for under some contract structures, energy thrown away.
Adding four hours of battery storage changes the product being sold. Instead of an intermittent midday block, the developer offers something closer to a dispatchable slice — power delivered when the buyer asks for it. That is a materially different bid, and it is why storage-attached tenders in India have found takers while bare solar tenders have gone begging.
Who gets paid when storage is bolted on
Attaching batteries to 42 GW of orphaned solar, or even a meaningful fraction of it, is a procurement event of real size. The beneficiaries sit in several distinct layers.
- Cell and module makers — lithium iron phosphate cells remain overwhelmingly Chinese-sourced, and India's domestic cell manufacturing base is thin relative to the deployment ambition.
- System integrators and EPC contractors — the firms that package cells, inverters, thermal management and controls into a containerised product and warrant it for a decade.
- Power conversion and grid-interface suppliers — inverters and transformers sized for bidirectional flow, a different specification from solar-only.
- Lenders — a storage-attached project carries a higher capital cost per megawatt but, if it wins a signed PPA, a bankable revenue line the solar-only version does not have.
The financing point deserves emphasis. A 42 GW pipeline without offtakers is stranded capital: money already spent or committed against contracts that do not exist. Storage raises the upfront bill but converts an unsellable asset into a sellable one. For a developer holding an idle project, that arithmetic can favour spending more.
Curtailment is a grid problem before it is a battery problem
Batteries at the project boundary treat a symptom. The underlying constraint is transmission and the willingness of discoms — many of them financially strained — to commit to long-dated purchases. Storage shifts power a few hours; it does not move power across states, and it does not repair a balance sheet.
The underlying constraint is transmission and the willingness of discoms — many of them financially strained — to commit to long-dated purchases.
Sarangi's framing is nonetheless significant because it comes from the ministry rather than from the industry. When a government secretary publicly identifies solar-only projects as the ones at risk, that is a signal to developers about where future tender design is heading. Firm and dispatchable renewable energy tenders, which specify delivery profiles rather than raw capacity, have been the direction of travel; a 42 GW overhang is the strongest argument yet for making them the default.
The read-across for energy investors
India is the second large market in a short span to make grid storage the binding constraint on renewables growth rather than generation itself. The investable consequence is that capital allocation within the clean energy complex keeps rotating away from panel manufacturing — a commoditised, oversupplied business — and toward cells, integration and grid hardware, where pricing power is better defended.
Broad equity markets closed the week firm. The S&P 500 tracker SPY finished at $765.72, up 0.41% on the day from a prior close of $762.60, with a session range of $764.17 to $767.85. The Nasdaq 100 proxy QQQ closed at $713.44, up 0.35% from $710.93, and the Dow tracker DIA ended at $532.22, up 0.89% from $527.51 — figures as of the last trade at 20:00 GMT on Friday, 21 August 2026. None of those moves reflects Indian energy policy, but they set the risk backdrop against which storage developers will be raising capital in the coming quarters.
What to watch from here
Three things will show whether the battery pivot is working. First, the shape of upcoming Indian tenders: how many specify storage or a delivery profile rather than nameplate solar capacity. Second, the rate at which the 42 GW backlog shrinks, and whether the 18 GW of unbatteried projects retrofit storage or simply stay idle. Third, cell supply — India's ability to source or manufacture the lithium iron phosphate cells this pivot requires, at a cost that lets a retrofitted project still clear a discom's tariff threshold.
If retrofits do not clear that threshold, the 18 GW does not become a storage opportunity. It becomes a write-down.
Key facts
- Solar capacity without offtakers: Up to 42 GW, per India's renewable energy ministry
- Most at-risk segment: About 18 GW of solar-only projects with no battery storage
- Source of statement: Santosh Sarangi, Secretary, Ministry of New and Renewable Energy, at the BNEF Summit, New Delhi, Friday
- Market backdrop: SPY closed $765.72 (+0.41%), QQQ $713.44 (+0.35%), DIA $532.22 (+0.89%) as of 20:00 GMT, 21 Aug 2026
Frequently asked questions
What did India's renewable energy ministry actually say?
Santosh Sarangi, Secretary of the Ministry of New and Renewable Energy, said on Friday at the BNEF Summit in New Delhi that up to 42 GW of Indian solar projects have yet to find offtakers, and that roughly 18 GW of those are solar-only projects without batteries, which he identified as the most likely to keep struggling to secure buyers.
What is curtailment and why does it matter here?
Curtailment is when a grid operator instructs a generator to reduce or stop output because the network cannot absorb the electricity. In India, solar output peaks in a narrow midday window when demand is already well supplied, so a share of generation is discarded. Batteries let developers shift that energy to hours when the grid actually needs it.
Why does adding a battery make a solar project easier to sell?
Without storage, a developer sells intermittent midday power that buyers already have in surplus. With storage, the same plant can deliver electricity in the evening peak when demand and prices are higher. That converts an inflexible product into something closer to dispatchable supply, which is what distribution companies are willing to sign long-term contracts for.
Who is the buyer for Indian solar power?
Most long-term power purchase agreements in India are signed by state-owned distribution companies, known as discoms, often via central intermediaries. Many discoms carry weak balance sheets, which makes them cautious about committing to 25-year contracts for power that arrives at times of day when they already have enough supply.
Which parts of the supply chain benefit from this shift?
Battery cell manufacturers, system integrators that package cells into containerised storage units, and suppliers of power conversion and grid-interface equipment such as bidirectional inverters and transformers. Solar module makers benefit least, since panel manufacturing is a commoditised segment with heavy global oversupply and thin pricing power.
Does adding storage solve India's curtailment problem entirely?
No. Batteries shift power by hours, but they do not move electricity between states or fix transmission bottlenecks, and they do not repair distribution companies' finances. Storage addresses the timing mismatch at the project boundary while the deeper constraints on grid capacity and offtaker creditworthiness remain unresolved.
Sources
Photo: Mark Stebnicki · Pexels Licence — source
