The reactor would have been rated at 1000 megawatts of thermal output, with a net plant output of 350 MW and a gross output of 380 MW. The reactor core was designed to contain 198 hexagonal fuel assemblies, arranged to form a cylindrical geometry with two enrichment zones. The inner core would have contained 18% plutonium and would have consisted of 108 assemblies. It would have been surrounded by the outer zone, which would have consisted of 90 assemblies of 24% plutonium to promote more uniform heat generation. The active fuel would have been surrounded by a radial blanket consisting of 150 assemblies of similar, but not identical, design containing depleted uranium oxide; outside of the blanket would have been 324 radial shield assemblies of the same overall hexagonal geometry. The primary and secondary control rod systems would have provided overall plant shutdown reliability. Each system would have contained boron carbide. The secondary rods were to be used only for SCRAM, and would have been required to be fully withdrawn before startup could be initiated.
Project economics and politics
The Clinch River Breeder Reactor was initially conceived as a major step toward developing liquid-metal fast breeder reactor technology as a commercially viable electric power generation system in the United States. In 1971 U.S. President Richard Nixon established this technology as the nation’s highest priority research and development effort. However, the Clinch River project was controversial from the start, and economic and political considerations eventually led to its demise.
Project costs
One issue was continuing escalation in the cost of the project. In 1971 the Atomic Energy Commission estimated that the Clinch River project would cost about $400 million. Private industry promised to contribute the majority of the project cost. By the following year, however, projected costs had jumped to nearly $700 million. By 1981 $1 billion of public money had been spent on the project, and the estimated cost to completion had grown to $3.0-$3.2 billion, with another billion dollars needed for an associated spent nuclear fuel reprocessing facility. A Congressional committee investigation released in 1981 found evidence of contracting abuse, including bribery and fraud, that added to project costs. Before it was finally canceled in 1983, the General Accounting Office of the Congress estimated the total project cost at $8 billion.
Technology costs
Another issue was the high cost of building and operating breeder reactors to produce electricity. In 1981, it was estimated that construction costs for a fast breeder reactor would be twice the cost of building a conventional light-water nuclear reactor of similar capacity. That same year it was estimated that the market price of mined, processed uranium, then $25 per pound, would have to increase to nearly $165 per pound in 1981 dollars before the breeder would become financially competitive with the conventional light-water nuclear reactor. United States electric utility companies were reluctant to invest in such an expensive technology.
Concerns about potential nuclear weapons proliferation were another serious issue for the commercial breeder reactor program, because this technology produces plutonium that potentially could be used to make nuclear weapons. Because of international concern about proliferation, in April 1977 President Jimmy Carter called for an indefinite deferral of construction of commercial breeder reactors. President Carter was a consistent opponent of the Clinch River project. In November 1977, in a statement explaining his veto of a bill to authorize funding for continuation of the project, Carter said it would be "large and unnecessarily expensive" and "when completed, would be technically obsolete and economically unsound." Furthermore, he said the project would have little value for determining the commercial viability of breeder technology in the United States. Congress persisted in keeping the Clinch River project alive over the President's objections, and Carter repeatedly chastised Congress for its actions. In a speech in 1979, after the House Science and Technology Committee had voted to proceed with the project over his opposition, he said "The Clinch River breeder reactor is a technological dinosaur. It's a waste of more than $1-1/2 billion of taxpayers' money. It's an assault on our attempts to control the spread of dangerous nuclear materials. It marches our nuclear policy in exactly the wrong direction.... This is no time to change America into a plutonium society." Instead of investing public resources in the breeder demonstration project, he urged attention to improving the safety of existing nuclear technology.
Cancellation of the project
The Clinch River Breeder Reactor Project was revived after President Ronald Reagan took office in 1981. In spite of growing opposition from Congress and analysts inside and outside the government, ground was broken and construction began. The project was finally terminated when, on October 26, 1983, the U.S. Senate voted 56-40 to deny any further financing for the project.
B&W mPower
In February 2013, plans were announced to build a B&W mPower small modular reactor at the site.