Supreme Court Rules Consumers Cannot Pay Power Plant Depreciation After Electricity Supply Ceases

In Delhi Electricity Regulatory Commission v. Tata Power Delhi Distribution Limited (2026 INSC 461), decided on May 7, 2026, the Supreme Court held that electricity consumers cannot be compelled to bear depreciation costs for a power plant that has stopped supplying electricity to them. The Court restored the order of the Delhi Electricity Regulatory Commission (DERC) and set aside the Appellate Tribunal for Electricity (APTEL) judgment that had permitted Tata Power Delhi Distribution Limited (TPDDL) to recover the entire capital cost of the Rithala Combined Cycle Power Plant through depreciation over fifteen years, even though the plant had ceased electricity supply after March 2018. This ruling has significant implications for electricity tariff regulation across India.

Background: The Rithala Power Plant Dispute

The Rithala Combined Cycle Power Plant was a gas-based power generation facility operated under a Power Purchase Agreement (PPA) with TPDDL. The PPA had a defined tenure during which the power plant was to supply electricity to consumers in the TPDDL distribution area. However, the plant ceased supplying electricity after March 2018 due to operational reasons. Despite this cessation, TPDDL sought to recover the full capital cost of the plant through depreciation charges spread over fifteen years, arguing that the asset continued to have remaining technical life and that the regulatory framework entitled it to full depreciation recovery regardless of whether the plant was actively supplying power. The DERC rejected this claim, holding that consumers should not be burdened with costs for a facility from which they were no longer receiving any benefit.

APTEL's Decision and the Appeal

TPDDL challenged the DERC order before APTEL, which overturned the regulator's decision. APTEL held that under the DERC Tariff Regulations, particularly Regulation 6.32, the distribution licensee had a right to recover depreciation over the normative life of the asset, and that this right was not contingent on whether the plant was actively generating or supplying electricity. APTEL's reasoning effectively meant that consumers would continue paying for the capital cost of an asset that provided them no service. The DERC appealed this decision to the Supreme Court, arguing that APTEL had misinterpreted the regulatory framework and that the tariff determination process must balance the interests of both the utility and the consumers.

The Supreme Court's Reasoning

The Supreme Court allowed DERC's appeal and restored the regulator's original order. The Court held that tariff determination is not merely a mathematical exercise but a regulatory balancing act that must account for the interests of consumers. The bench observed that consumers cannot be required to pay for a service they no longer receive. The Court clarified that Regulation 6.32 of the DERC Tariff Regulations does not create an absolute and unconditional right for the licensee to recover depreciation from consumers even after the asset has ceased supplying electricity. Depreciation recovery, the Court held, cannot be divorced from the approved PPA period and the actual supply of electricity. Once the plant stops generating power for the consumers, the regulatory justification for passing on its capital costs through tariffs ceases to exist. The Court also emphasised that the Electricity Act, 2003, requires regulatory commissions to balance the interests of consumers and utilities, and that a mechanical application of depreciation norms without regard to whether consumers are receiving any benefit would defeat this statutory purpose.

Implications for Electricity Tariff Regulation

This judgment sets an important precedent for electricity tariff disputes across India. Distribution companies that have stranded or underutilised power assets will find it harder to pass on capital costs to consumers if those assets are no longer supplying electricity. State electricity regulatory commissions now have clear Supreme Court backing to disallow depreciation recovery for non-operational plants. For consumers, the ruling means that tariffs should reflect only the actual cost of services received, not the sunk costs of infrastructure that is no longer beneficial to them.

Practical Takeaways

The Supreme Court's ruling in DERC v. Tata Power Delhi Distribution Limited establishes that the regulatory compact between utilities and consumers requires a nexus between the costs recovered through tariffs and the services actually provided. Depreciation recovery under tariff regulations is not an absolute entitlement but is subject to the overriding principle that consumers should pay only for services they receive. Distribution licensees must factor in the risk of asset stranding when making investment decisions, as the regulatory framework does not guarantee full cost recovery if the asset ceases to serve consumers. For regulatory commissions, this judgment reinforces their authority to protect consumer interests in tariff-setting proceedings, even when the tariff regulations appear to provide for mechanical cost recovery. The decision is expected to influence pending and future disputes involving stranded power assets, renewable energy purchase obligations, and the broader transition of India's power sector away from older thermal generation assets.