The Little-Known Nuclear Deal That Could Help Our Climate Crisis

“And then all wars ended / …The Pentagon was turned on its side and painted purple, yellow & green… / The energy from dismantled nuclear weapons provided free heat and light…”

—Terry Riley, “A Rainbow in Curved Air” (1969)

On a cold, rainy day in November 2013, a small group of Russian and American officials gathered on a pier at the Great Port of St. Petersburg, a bleak industrial landscape far removed from the city’s majestic baroque buildings. They were there to see off a freighter called the Atlantic Navigator. Its cargo comprised 40 cylindrical canisters, each of which contained uranium that had once been part of Soviet warheads. Some of the spectators standing in the rain had scrawled messages on the canisters. “Happy Trails to Baltimore,” one read. “Congratulations on the last shipment! Stay safe!” read another.

In total, the shipment contained material from roughly 80 nuclear bombs. But the hazardous content had been diluted — converted from highly enriched uranium (HEU) to the low-enriched variety, no longer suitable for explosions but ideal for nuclear reactor fuel. Upon arrival at the Port of Baltimore several weeks later, it would be transferred to facilities for fuel fabrication and then delivered to nuclear power plants throughout the United States.

This final voyage marked the close of a remarkable chapter in the history of U.S.-Russia relations, nuclear security and energy production. The shipments had begun in 1995, as part of an agreement known by several names; insiders tended to call it the “HEU Purchase Agreement” or “HEU Deal,” while the media preferred “Megatons to Megawatts.”

By its conclusion, a massive quantity of weapons-grade uranium — enough for about 20,000 warheads — had been diluted and fashioned into fuel pellets. The resulting fuel supplied roughly 10% of all electricity generated in the U.S. during those 18 years. The program has been called “the deal of the century,” “one of the most intelligent national security initiatives in U.S. history,” and “the single biggest instance of arms reduction in the nuclear age.”

The Megatons to Megawatts initiative offers many lessons for navigating overlapping crises in a rapidly changing world. The proposition of turning nuclear weapons into low-carbon energy is even more compelling today, given rising electricity demand and the urgent need for decarbonization.

But this astonishing success story is largely unknown. It has gone unmentioned in the memoirs of major Cold War figures, and few have heard the name of the man, Thomas Neff, who dreamt up the idea and labored for years behind the scenes to make it a reality.

Jeffrey Hughes, a retired government official who worked on the program, hopes to change that. He co-directs Columbia University’s new Megatons to Megawatts Evaluation Project, and he recently published an in-depth study detailing the program’s ups and downs.

Through the project, some of the original participants, along with other stakeholders, have begun to gauge prospects for such a program in the future. Could this swords-into-plowshares concept be resurrected in some form — to fight climate change and reduce nuclear risks at the same time?

‘A Grand Uranium Bargain’

I spoke with the late Thomas Neff via Zoom in March 2023, in one of his final interviews, a little more than a year before his death. Neff was a physicist who worked at MIT’s Center for International Studies as an expert on the international uranium market. From his home in Concord, Massachusetts, he explained how he had come up with his “crazy idea.”

It was 1991, and the Soviet Union was disintegrating. The government was bankrupt, and the member states were plunged into a severe economic crisis. Centralized authority had collapsed as tens of thousands of nuclear warheads remained scattered around the region. Weapons-grade uranium was being stored in dilapidated buildings with broken windows. It was a nuclear proliferation nightmare.

“These things are horribly insecure, nobody’s getting paid, you’ve got a million people working for this ministry, and a lot of them have access to the materials and weapons or parts and pieces,” Neff recalled thinking at the time. Many of these weapons were already slated for dismantling or shelving as part of disarmament agreements reached with the U.S. in recent years. But now they were at risk of getting stolen or sold to the highest bidder. Also worrisome was the possibility that personnel with nuclear expertise, now in urgent need of money, might sell their know-how to terrorists or hostile regimes. Neff and many other observers feared that the results could be catastrophic.

In an op-ed for The New York Times that October, Neff proposed, as the headline put it, “A Grand Uranium Bargain.” What would come to be a storied historical text reads as strikingly understated today. The language is dry and technocratic, with no mention of the phrase “swords into plowshares,” which would become all but obligatory in describing the program in the coming years.

“Could this swords-into-plowshares concept be resurrected in some form — to fight climate change and reduce nuclear risks at the same time?”

“The Soviet Government is struggling to transform itself economically and politically while maintaining control of more than 24,000 nuclear weapons in the newly independent republics,” Neff wrote. “Mikhail Gorbachev has pledged to dismantle thousands of them, but the bankrupt Government may not be able to pay for doing so in ways that prevent misuse or wider proliferation.”

Neff offered his solution: “The warheads contain substantial amounts of valuable material that can be processed for use in commercial nuclear power plants. It may be advantageous for the U.S. to buy or barter for such materials and turn them safely to commercial use.”

The scheme promised to help solve several problems at once. Russia would receive a desperately needed infusion of cash. A kilogram of highly enriched uranium converted into fuel went for about $24,000, twice as much as gold, and each weapon contained material worth up to half a million dollars. Once it was down-blended into low-enriched uranium, the U.S. could turn it into cheap fuel to generate electricity (low-carbon, as an under-appreciated bonus). Perhaps most importantly, the threat of nuclear chaos would be much reduced.

The transmutation of atomic warheads into civilian electricity wasn’t an entirely new idea. In 1966, an official in Lyndon B. Johnson’s administration proposed taking weapons-grade uranium and converting it for peaceful purposes, including electricity. But the idea didn’t amount to anything until Neff advanced a specific proposal at the right moment.

“Technically, I knew it would work,” Neff told me. “That’s the physics part. So that was not the big problem. It was more a matter of the politics of doing it.”

Neff was plugged into a network of American and Soviet scientists and government operatives who had begun to form ties in the waning years of the Cold War. At the State Plaza Hotel in Washington, D.C., several days before his op-ed was published, Neff attended a meeting on the emerging nuclear perils. In the hallway, he approached Victor Mikhailov, head of the Soviet weapons program, who was taking a smoke break. Speaking through Mikhailov’s interpreter, Neff outlined his idea and handed him a draft of his op-ed. Neff told me that Mikhailov instantly grasped the potential benefits.

What followed was a tale of almost cinematic intrigue as Neff poured his energies into getting the George H.W. Bush administration on board and serving as a back channel between the two countries. He traveled repeatedly to the former Soviet Union (“Never drink with a Russian,” he advised me.). He faxed unsolicited memos to various government officials; he flew frequently to Washington, D.C, showing up at meetings with his luggage in tow. In sum, he leveraged his unique combination of physics expertise, mastery of the uranium market, network of professional connections and sheer obstinacy to bring his idea to fruition.

And it worked. Less than a year after his op-ed was published, in September 1992, the Bush administration announced the contours of a deal. William J. Broad, The Times’ longtime science correspondent, reported, “Last week a new kind of unthinkable came to pass, marking a milestone in the transformation of nuclear swords into plowshares.” The article quotes a Department of Energy official: “Instead of lighting up mushroom clouds, this stuff is going to light up homes in the United States with electricity,” he said. “It’s kind of incredible.”  

The Deal

Per the agreement, the U.S. government promised to buy a fixed annual amount of down-blended uranium from the Russian Federation. The two governments partnered with commercial enterprises to execute the arrangement.

After multiple delays and disputes about compensation, the first shipment arrived in the Port of Baltimore in June 1995.

A rhythm developed in the following years. In four formerly secret “nuclear cities,” Russian technicians carried out different aspects of the work: they used machines to slice the weapon components into fine metal shavings and then oxidized, purified and fluorinated the shavings before blending the material with uranium that was only slightly enriched. The final product was a substance enriched to about 3-5%, rather than roughly 90%.

American experts visited the Russian facilities and monitored activities, taking notes and Polaroid photographs, to ensure that the Russians were complying with requirements. Russian experts were also permitted to visit the U.S. facilities in Paducah, Kentucky and Portsmouth, Ohio, for monitoring. Over the years, these visits fostered goodwill and the exchange of technical knowledge that benefited both nations. The project was so rewarding that one person who was involved told me some of the participants postponed retirement to continue their work.

“For two decades, one in 10 light bulbs in America has been powered by nuclear material from Russian nuclear warheads.”

The revenue from the deal was essential to stabilizing the Russian nuclear sector. Mikhailov was now able to pay his employees, ensuring that they wouldn’t be tempted to leave their posts or peddle their nuclear expertise. By the end of the program, the U.S. had forked over about $17 billion to Russia. Because it was a commercial agreement, it was at no taxpayer expense. And it helped integrate Russia into the global economy.

“The genius of the HEU deal was to tie a national security imperative to a genuine market need,” Daniel Poneman, who served as the U.S. Department of Energy deputy secretary in the Obama administration, told me.

As the program came to an end in November 2013, Ernest Moniz, President Obama’s Secretary of Energy, celebrated the accomplishment, calling it “one of the most successful nuclear nonproliferation partnerships ever undertaken.” Since the program’s start, 101 of the 103 nuclear reactors in the United States received fuel that was once part of Soviet bombs. This fuel supplied about half of the country’s nuclear power. Moniz noted, “For two decades, one in 10 light bulbs in America has been powered by nuclear material from Russian nuclear warheads.”

Equally crucial, though harder to measure, is what the program may have prevented: the bombs not dropped, accidents that didn’t occur and entities that didn’t acquire nuclear weapons. In the absence of Megatons to Megawatts, we’d likely be living in an even more dangerous world.

Resurrecting Neff’s Brainchild

When I spoke with Neff a decade later, in March 2023, Russia and Ukraine were at war, and U.S.-Russia relations were at a nadir. Although prospects looked grim, I had to ask: Can Megatons to Megatons be resurrected? Can something like this happen again?

“Never say never,” he told me. “But when the Soviet Union broke up, they were really bankrupt. They had no money. It was a propitious time to go and pitch them something that would give them hard currency.”

In the years since our conversation, the war in Ukraine has dragged on, and what’s left of the post-Cold War world order has eroded under the Trump administration. Such prospects look, if anything, bleaker. But back in the early 1990s, the idea also seemed unlikely. As Hughes, the retired government official, noted when we spoke: “It could have easily run off the rails and been just determined to be too hard at the outset.”

Several nuclear security and nonproliferation experts told me they still believe the deal could serve as a workable model for the future. “The idea that Dr. Neff came up with is, of course, one that we could use again and should use again,” Pranay Reddy Vaddi, at the time a senior nuclear fellow at MIT’s Center for Nuclear Security Policy, told me.

One point in its favor is the renewed interest in nuclear power, driven by a combination of climate concerns and rising energy demand. Some nuclear startups in the U.S. are working with high-assay low-enriched uranium (HALEU) fuel, which is enriched to between 5% and 20%, making it harder to produce from scratch and more conducive to down-blending from weapons-grade uranium.

A Megatons to Megawatts sequel could take different forms. One possibility would be another deal with Russia — most likely in a post-Trump, post-Putin era. Another would be a deal with a different country, and a third would be to down-blend our own supply.

Megatons to Megawatts 2.0?

Russia still has the largest stockpile of atomic weapons in the world — an estimated 5,459. (The U.S. is not far behind with 5,277.) Hughes believes several factors might make such a deal attractive to the Russians again.

The Russian economy has been battered by sanctions and an ongoing war that has resulted in 1.2 million Russian casualties, including 325,000 deaths, according to a recent Center for Strategic and International Studies report. “Russian manufacturing is declining, consumer demand is weakening, inflation remains stubbornly high, and the country faces a labor crunch,” the report states. Economic growth last year was at 0.6%.

Like after the Cold War, a postwar, post-Putin Russia might view this type of deal as an economic lifeline — a way to demonstrate goodwill and take steps toward reintegrating into the global economy. The U.S. could even stipulate a new agreement in exchange for lifting sanctions.

“In the absence of Megatons to Megawatts, we’d likely be living in an even more dangerous world.”

Some members of civil society are trying to renew ties between the two countries. The New Strategic Arms Reduction Treaty (New START), a bilateral agreement between the U.S. and Russia, expired on February 5. Two days prior, Russian and American experts convened to discuss possibilities for future dialogue on arms reduction and nonproliferation. Cross-national relationships between scientists helped lay the groundwork for Megatons to Megawatts the first time around and could do so again.  

Beyond Russia

Today, the most hotly contested uranium on the planet is the 440 kilograms that Iran has enriched to 60% — enough for about 10 bombs, were enrichment to continue. The U.S. sought to destroy that material in bunker-busting strikes last June, but it is widely believed that at least some of it still exists.

Since the Trump administration launched its full-scale war on the country in February, the fate of that material has been a major sticking point. Last month, Axios reported that the prospect of financial compensation had come up in talks: the U.S. could release $20 billion in frozen funds if Iran agrees to surrender the material. 

Scott Roecker, vice president of nuclear materials security at the Nuclear Threat Initiative, a Washington-based nonprofit focused on reducing nuclear risks, said that one possibility is to relocate this material to the U.S. In his view, the best-case scenario would be to take it to one of our National Laboratories, down-blend it, and use it as HALEU (fuel enriched to between 5% and 20%, which some startups plan to use). “The level of hostility between the two countries doesn’t bode well for such an agreement,” he acknowledged, “but there are pretty big incentives on both sides to reach some sort of a deal.” (The White House did not reply to a request for comment.)

Roecker also said he could envision a new iteration of Megatons to Megawatts emerging as part of a broader arms-reduction agreement, whether with Russia or China or another country. “It could be like a sweetener or an incentive to reduce the number of nuclear weapons.”

All of this conjecture might seem hopelessly naïve with Trump in power and nations pulling back from cooperation of all kinds. But geopolitical circumstances can change swiftly. “I don’t rule anything out,” Greg Dwyer, who oversaw the program when he worked at the Energy Department during the Obama administration, told me. “In my business, I know things come out of the blue all the time. And there are opportunities there.”

Finally, the U.S. could unilaterally choose to down-blend some of its own stocks of weapons-grade uranium for use in commercial nuclear reactors. During the original Megatons to Megawatts program, the U.S. followed Russia’s lead, down-blending the equivalent of several thousand bombs. Highly enriched uranium, which is also used for naval propulsion and research reactors, is costly and risky to maintain, so there are self-interested reasons for countries to shrink their inventories.

In fact, in July of last year, the Department of Energy announced plans to down-blend 2.2 metric tons of highly enriched uranium at a facility in South Carolina. The impetus was the growing demand for HALEU. The Energy Department document cited the goal of “reducing stockpiles of weapons-usable fissile materials, setting a nonproliferation example for other nations, and allowing peaceful, beneficial reuse of the material to the extent practical.”

A Precedent For The Future

Neff died on July 11, 2024, at the age of 80. He earned a couple of glowing obituaries, but otherwise, his death attracted little notice.

Although he never held a government appointment, he remained heavily involved in the program throughout its life, monitoring it closely and intervening through meetings and memos whenever he thought it needed help getting back on track. “In reality,” he wrote in an American Physical Society newsletter in 1998, “a new idea is much like a child: conceiving one is nowhere near as hard or time-consuming as raising one.”

Of course, there were many others who were vital to the project’s success: presidents, cabinet members, government officials such as Daniel Poneman, Jeffrey Hughes and Greg Dwyer — as well as the anonymous civil servants and inspectors in both countries who carried out the day-to-day work of executing the program.

“The lessons of history show us that none of this is out of theoretical reach, even if, for now, it seems beyond our grasp.”

For all its virtues, the program wasn’t perfect. The most common criticism was that it contributed to the atrophying of the domestic uranium industry. After the program lapsed, the U.S. remained dependent on Russia for low-enriched uranium, which Russia was now enriching from scratch. When Russia invaded Ukraine in 2022, the U.S. relied on Russia for about a quarter of its uranium enrichment. (In May 2024, President Biden signed a law restricting imports of enriched uranium from Russia, though the ban can be waived. Efforts are underway to revive the industry in the U.S.) There are also drawbacks to civilian nuclear energy, of course, such as its production of long-lived radioactive waste. Still, Megatons to Megawatts is a program worth remembering and emulating.

“The beauty of the HEU Purchase Agreement was it set a precedent that it can be done,” Dwyer told me. “No one can come back and say that’s impossible.”

What would it take to turn nuclear swords into plowshares again on a meaningful scale? We might need a new Neff — someone with the imagination, knowledge and obsessive tenacity to apply the idea to today’s conditions. We’d also need commitment at the highest level of government and a federal workforce with the technical expertise and competence to see it through. The lessons of history show us that none of this is out of theoretical reach, even if, for now, it seems beyond our grasp.