EXPLAINER: Mambilla Power Plant Saga: 23 Years, 3 Presidents, 1 Final Award for Nigeria

The Origin (2003): The then-minister of Power, Olu Agunloye awarded Sunrise Power and Transmission Company a contract to build the 3,050MW Mambilla Hydropower Plant in Taraba State on a build-operate-transfer basis, valued at $6 billion.

A Contested Mandate: Former President Olusegun Obasanjo has repeatedly denied authorising the deal, saying no minister could commit Nigeria to a project of that size without his express consent — and that he had told Agunloye to step the idea down before it went to the Federal Executive Council.

The Project Stalls: Despite the contract, construction never meaningfully progressed, and the Mambilla project became one of Nigeria’s most prominent stalled infrastructure ambitions, dragging on across successive administrations.

First Arbitration Filed (2017): After years without resolution, Sunrise took Nigeria to the ICC International Court of Arbitration on October 10, 2017, seeking $2.354 billion in damages for alleged breach of contract.

A Settlement Attempt (2020): Nigeria and Sunrise entered a settlement agreement and addendum in 2020 intended to end the dispute — but former President Muhammadu Buhari later said he personally refused to approve the deal when it was presented to him, convinced there was no basis for Sunrise’s claim.

The Settlement Collapses: With the 2020 agreement allegedly unhonoured, Sunrise returned to arbitration, this time seeking $400 million — the combined settlement sum and a default penalty — triggering a second, parallel dispute track.

Nine Years Of Arbitration: From the first filing in 2017 to the final award in 2026, the arbitration proceedings themselves ran nine years, presided over by a three-member ICC panel chaired by Melaine van Leeuwen.

The Final Ruling (September 2026): The tribunal dismissed both Sunrise’s $2.35 billion claim and its $400 million settlement demand, finding no breach by Nigeria under either the original contract or the settlement agreement.

Costs Reversed Onto Sunrise: Rather than Nigeria paying out, the panel ordered Sunrise and its promoter, Leno Adesanya, to refund $11.82 million in Nigeria’s legal costs — with Adesanya held personally bound by the arbitration agreement — plus a 75 per cent share of arbitration costs, with 10 per cent annual interest on unpaid sums.

A Pattern Beyond Mambilla: The late former President Buhari had linked the case to a broader trend of “invisible contractors” pursuing Nigeria for large out-of-court settlements, comparing it to the earlier P&ID saga — making this ruling one of several recent wins for Nigeria against contested legacy contracts.