A 25-year power deal locked at Rs 2.64/unit. Then a regulator changed the rules. The Supreme Court just said: no takebacks.

They signed a 25-year power purchase agreement at Rs 2.64 per unit. Then the regulator changed the pricing formula. The generators went to court to raise the rate.

For nearly a decade, wind energy generators in Gujarat sold electricity under a deal they had freely negotiated. Then, in 2013, the Central Electricity Regulatory Commission (CERC) amended its regulations. The new rule required payment at the "actual pooled cost" — a figure that changes every year — rather than at the fixed price locked in their contracts. The generators saw an opportunity. They petitioned the Gujarat State Commission to revise their tariff upward. The State Commission agreed. The distribution company, Gujarat Urja Vikas Nigam Limited (GUVNL), refused to pay more. The question that reached the Supreme Court was simple: can a contract be reopened just because the market shifted?

The courtroom fell still when the coercion argument was read aloud — a single sheet of paper, the generators' claim that they had signed under duress. On the table before the bench lay a stack of Power Purchase Agreements, each one signed, each one bearing the fixed price of Rs 2.64. The judgment that followed would kill the appeal in a single, decisive line.

The deal was signed at Rs 2.64

Gujarat Urja, the bulk buyer of electricity for distribution companies across the state, entered into Power Purchase Agreements (PPAs — long-term contracts to buy electricity) with several wind energy generators, including Renew Wind Energy (Rajkot) Private Limited. These PPAs were signed under the Renewable Energy Certificate (REC — a market-based certificate earned for every unit of green power produced, which can be sold separately) scheme.

The PPAs fixed the electricity price at Rs 2.64 per unit. The term was 25 years. Both sides signed voluntarily. No regulator reviewed or approved the tariff before signing. The contracts were straightforward commercial documents.

Then the regulator changed the formula

In 2013, CERC amended its REC Regulations. The key change: instead of saying the tariff "shall not exceed the pooled cost" of power purchase, the new regulation said the tariff "shall be at the pooled cost." This meant the price would now float year-on-year, tracking the actual average cost at which distribution companies bought power from all sources.

The wind generators argued that this amendment applied to their PPAs too — even though they had signed their contracts years before the change. They claimed the fixed price of Rs 2.64 was no longer viable. They wanted the tariff revised to the year-on-year Average Pooled Power Purchase Cost (APPC — the average price at which distribution companies buy electricity from all sources).

The State Commission said yes

In July 2015, the Gujarat Electricity Regulatory Commission allowed the generators' petition. It directed GUVNL to revise the tariff from the fixed rate to the year-on-year APPC. The order applied to all similarly placed generators — not just those who had filed the petition.

GUVNL appealed to the Appellate Tribunal for Electricity (APTEL — the tribunal that hears appeals from electricity regulators). In December 2018, APTEL dismissed the appeal and upheld the State Commission's order. The generators also raised a new argument before APTEL: they claimed they had signed the PPAs under coercion and duress, because GUVNL held a dominant position in the market. APTEL accepted this argument as well.

Why the Supreme Court stepped in

GUVNL appealed to the Supreme Court. The core issues before the bench — Justices Sanjay Kishan Kaul, S. Ravindra Bhat, and M.M. Sundresh — were threefold.

First, did the State Commission have the jurisdiction to reopen a PPA that had been voluntarily signed without any regulatory approval requirement? Second, did the 2013 CERC amendment apply retrospectively to PPAs executed before the amendment? Third, was the plea of coercion and duress actually established by the generators?

The court answered all three questions in favour of GUVNL.

The contract stood on its own feet

The Supreme Court held that in the absence of specific regulatory provisions mandating prior approval of PPAs by the State Commission for renewable energy sources, a PPA entered into by parties exercising free choice cannot be invalidated for want of such approval. The contract stood on its own feet.

On the second issue, the court ruled that the 2013 amendment to the CERC REC Regulations was prospective — it applied only to PPAs signed after the amendment took effect. PPAs executed before 2013 remained governed by the pre-amendment regime. Their tariff terms could not be retrospectively altered.

The court observed that "a PPA is a commercial transaction freely entered into." Neither party can seek modification of agreed tariff terms merely because of subsequent regulatory changes, unless the regulations expressly provide for retrospective application. The bench wrote that single line — and with it, the generators' case collapsed.

The coercion argument collapsed

The most striking part of the judgment was the court's treatment of the coercion plea. APTEL had accepted the generators' claim that they signed the PPAs under duress because GUVNL was a monopoly buyer. But the Supreme Court found this reasoning hollow.

The court held that a party alleging fraud, coercion, duress, or undue influence must prima facie establish it by laying out material facts with particularity. APTEL could not render findings on coercion without proper pleadings, adequate evidence, or without conducting a probe in a casual or cavalier way.

There was no evidence on record to show that the generators had signed under threat or compulsion. They were sophisticated commercial entities. They had negotiated the PPAs. They had operated under them for years. The coercion argument appeared to be an afterthought — raised only when the market turned favourable to reopening the deal.

The smell of old paper hung in the air as the bench read its findings. The stack of PPAs on the table — each one signed, each one at Rs 2.64 — told the real story. There was no duress in those pages. There was only a deal that had soured in the generators' favour and then soured again when the market changed.

The procedural journey: a decade of litigation

The case had travelled a long road before reaching the Supreme Court. In July 2015, the Gujarat Electricity Regulatory Commission allowed the generators' petition and directed tariff revision. GUVNL appealed to APTEL, which dismissed the appeal in December 2018 and affirmed the State Commission's order. The generators then raised the coercion argument before APTEL, which accepted it.

GUVNL approached the Supreme Court for the first time in February 2019. The court disposed of the matter with liberty to seek review or rectification before APTEL. The generators filed a review petition before APTEL in July 2020, but it was dismissed. Finally, in April 2023, the Supreme Court heard the final appeal and allowed it.

The court set aside the orders of APTEL dated December 6, 2018, and July 24, 2020, as well as the State Commission order dated July 1, 2015. The PPA terms were upheld as binding. The fixed price of Rs 2.64 per unit remained in force.

The legal framework: what the court interpreted

The Supreme Court engaged with several provisions of the Electricity Act, 2003. Section 86(1)(a), (b), and (e) — which define the functions of the State Commission — were the primary interpretation targets. The court held that these provisions did not require prior approval of PPAs for renewable energy sources in the absence of specific regulatory mandates.

Section 62, which deals with the determination of tariff, and Section 64, which lays down the procedure for tariff orders, were interpreted to support the view that voluntarily negotiated tariffs could not be reopened without clear regulatory authority. Section 181, which empowers State Commissions to make regulations, was interpreted consistently with this view.

The court also examined Regulation 5 of the CERC REC Regulations, 2010, which deals with eligibility and registration for certificates. The 2013 amendment to this regulation was held to be prospective, not retrospective. Rule 8 of the Electricity Rules, 2005, which governs tariffs of generating companies under Section 79, was applied to reinforce the principle of contractual sanctity.

Precedents that guided the court

The Supreme Court relied on several of its own decisions. In Gujarat Urja Vikas Nigam Ltd. v. Solar Semi-Conductors Power Ltd. (2017), the court had held that PPAs cannot be reopened without specific regulatory authority. In Transmission Corporation of Andhra Pradesh Ltd. v. Sai Renewable Power Pvt. Ltd. (2010), the court had emphasised the binding nature of commercial contracts. In Gujarat Urja Vikas Nigam Ltd. v. EMCO Ltd. (2016) and Gujarat Urja Vikas Nigam Ltd. v. ACME Solar Technologies (Gujarat) Pvt. Ltd. (2017), the court had reinforced the principle that regulatory changes do not automatically alter existing contractual terms.

The court also cited PTC India Ltd. v. CERC (2010), which dealt with the scope of regulatory authority, and Hindustan Zinc Ltd. v. Rajasthan Electricity Regulatory Commission (2015), which addressed the limits of retrospective application of regulations. In Kerala State Electricity Board v. Principal Sir Syed Institute (2020), the court had held that contractual obligations must be honoured unless there is clear statutory authority to modify them.

What this means for power contracts

The judgment sends a clear signal to the renewable energy sector: a contract is a contract. If you sign a 25-year PPA at a fixed price, you cannot walk into a regulator's office years later and demand a higher rate simply because the regulatory framework has changed.

For distribution companies like GUVNL, the ruling provides certainty. They can plan their power purchase costs without fear of retrospective tariff revisions. For generators, the message is equally clear: negotiate your terms carefully at the time of signing, because the courts will hold you to them.

The court's ratio decidendi established four key principles. First, in the absence of specific regulatory provisions mandating prior approval of PPAs by the State Commission for renewable energy sources, a PPA entered into by parties exercising free choice cannot be invalidated for want of such approval. Second, the 2013 amendment to CERC REC Regulations applies prospectively; PPAs executed prior to the amendment remain governed by the pre-amendment regime and their tariff terms cannot be retrospectively altered. Third, a party alleging fraud, coercion, duress, or undue influence must prima facie establish it by laying out material facts with particularity; APTEL cannot render findings on coercion without proper pleadings, adequate evidence, or without conducting a probe in a casual or cavalier way. Fourth, a PPA is a commercial transaction freely entered into; neither party can seek modification of agreed tariff terms merely because of subsequent regulatory changes, unless the regulations expressly provide for retrospective application.

THE PLAY: When drafting a long-term PPA, include an express clause stating whether tariff revisions will follow future regulatory changes — silence means the contract price is final.

The Supreme Court allowed GUVNL's appeal, set aside the orders of APTEL and the State Commission, and upheld the original PPA terms. The fixed price of Rs 2.64 per unit remained binding. The 25-year deal stayed exactly as it was written. The generators had bet on a market shift to break their contract — and lost.