APTEL Sets Aside INR 6.44/kWh Solar Tariff Order, Upholds INR 5.68/kWh Rate For 5 MW Siwana Project In Haryana

The Appellate Tribunal for Electricity (APTEL) has set aside an order of the Haryana Electricity Regulatory Commission (HERC) that directed the Haryana Power Purchase Centre (HPPC) to pay a higher solar tariff of ₹6.44 per kWh to M/s Siwana Solar Power Projects Ltd. The judgment was delivered on September 18, 2026, by a bench comprising Officiating Chairperson Seema Gupta and Judicial Member Virender Bhat.

The dispute relates to a 5 MW solar power project operated by Siwana Solar Power Projects in Bhiwani, Haryana. The company had entered into a Power Purchase Agreement (PPA) with the relevant authorities in February 2014 for the sale of electricity. Under the PPA, the applicable tariff was to be the lowest among specified benchmark rates, including rates discovered through competitive bidding.

During the procurement process, a tariff of ₹6.44 per kWh was discovered. Siwana had initially sought application of higher generic tariffs, but subsequent regulatory and judicial proceedings established ₹6.44 per kWh as the applicable rate at that stage.

The tariff dispute later changed following litigation involving competitive bidding by other solar developers. A lower tariff of ₹5.68 per kWh was subsequently established based on benchmark costs applicable to later years. HPPC began making payments to Siwana at ₹5.68 per kWh from March 2019.

The parties also undertook financial reconciliations concerning earlier payments and pending dues. Siwana accepted a settlement covering outstanding amounts up to March 2019. The settlement and related proceedings were subsequently upheld by the Supreme Court.

In 2024, Siwana approached HERC through Petition No. 26 of 2024, seeking restoration of the ₹6.44 per kWh tariff and payment of the differential amount over the ₹5.68 per kWh rate. HERC dismissed the petition on November 12, 2024, holding that the matter was barred by res judicata, a legal principle that prevents the same issue from being litigated again after it has been finally decided.

Siwana did not challenge that HERC order and instead filed another petition, No. 78 of 2025, seeking substantially the same relief. In May 2026, HERC took a different view and held that the earlier settlement covered only dues up to March 2019. It directed HPPC to pay ₹6.44 per kWh prospectively and reimburse the differential amount, along with 9.15% interest.

HPPC challenged the decision before APTEL. The Tribunal found that the prayers in the 2024 and 2025 petitions were identical and that HERC’s earlier dismissal had not been challenged. APTEL held that the tariff issue had therefore attained finality and could not be reopened by separating past and future payments.

Accordingly, APTEL set aside HERC’s May 2026 order and held ₹5.68 per kWh to be the binding tariff between the parties. HPPC was consequently relieved from paying the higher tariff and the associated differential amount and interest.