SolarReserve's $1B Crescent Dunes solar tower barely ran — taxpayers out $225M+

Crescent Dunes, near Tonopah, Nevada, was meant to prove concentrated solar power could keep the lights on after dark: 110 MW from more than 10,000 mirrors focusing sunlight on a 640-foot tower, heating molten salt to over 1,000 degrees so the plant could run ten hours on stored heat. The Department of Energy backed Tonopah Solar Energy with a $737 million loan guarantee in 2011, and utility NV Energy signed up as sole customer under a 25-year power purchase agreement running to 2040.

The plant entered commercial operation in November 2015. Within a year a leak opened in the hot-salt tank — the component that made the whole concept work — and shut it down for eight months. It returned in July 2017 but never delivered reliably: NV Energy issued a default notice on January 1, 2019, and the plant stopped producing in April. In June the utility moved to terminate the PPA because the plant had 'failed to produce the requisite energy levels.' Its power sold for about $139 per MWh while new Nevada photovoltaic farms were signing below $30.

With its only customer leaving and the DOE issuing default notices of its own, Tonopah Solar Energy filed for Chapter 11 in Delaware on July 30, 2020, still owing $425 million on the federal loan. A settlement recovered just $200 million for taxpayers — a shortfall of at least $225 million on a plant that cost roughly $1 billion to build.

$1B project; owner Tonopah Solar Energy went bankrupt owing $425M on the DOE loan; a $200M settlement left taxpayers at least $225M short; SolarReserve collapsed.

SolarReserve scaled an unproven design straight to world's largest: the failure modes of a utility-scale molten-salt tower were unknown when the project was financed.

The entire capital stack was structured debt — a $737M federal loan guarantee plus co-investors — with no deep sponsor balance sheet to absorb repair costs or revenue loss during outages.

The 25-year fixed-price PPA at ~$139/MWh assumed the technology would perform from day one; every outage pushed the plant further underwater as PV costs collapsed below $30/MWh during construction.

A single-customer contract gave the plant no second chance: when performance slipped, NV Energy could — and did — walk, which is what turned a repair problem into a bankruptcy.

First-of-a-kind technology, a 25-year fixed-price offtake and all-project debt leaves zero margin for commissioning surprises; pilot smaller and make the offtaker share the technology risk.

A Delaware court approved the reorganization in December 2020, with Spanish contractor ACS's Cobra unit taking operational control and the plant eventually returning to service for NV Energy. The reprieve didn't last: in January 2026 Tonopah Solar Energy filed for Chapter 11 a second time, saying it owed about $173 million to lender Crescent Dunes Finance and planned to sell the project itself. SolarReserve, the startup that developed the plant, is gone. The US concentrated-solar-tower industry effectively died with it, while PV plus batteries took the market it was built for.