China Builds the First Reactor That Eats Nuclear Waste

Somewhere in the southern Chinese city of Huizhou, engineers are bolting together the final segments of a superconducting linear accelerator. By 2027, this machine will fire protons at 80% the speed of light into a pool of molten lead-bismuth alloy. The goal is not to discover new particles. It is to eat nuclear waste.

The project is called CiADS — China initiative Accelerator-Driven System — and it will be the first megawatt-scale facility of its kind to actually operate. Scientists have theorized about accelerator-driven reactors for decades. Belgium’s MYRRHA project has been under development since the late 1990s. The United States funded the NEWTON program in 2025 to build better accelerator components. But China is the first to reach the point of switching the machine on.

The Unburned 99%

Conventional nuclear power plants use less than 1% of the uranium in their fuel rods. The rest becomes waste — a cocktail of isotopes, some of which remain dangerously radioactive for over 100,000 years. Countries bury this waste deep underground and hope geology does the rest.

Minor actinides — heavy radioactive elements produced as byproducts in nuclear reactors, including neptunium, americium, and curium. Their half-lives range from hundreds to millions of years, making them the most problematic components of nuclear waste.

The math is stark. A single commercial reactor generates about 20-30 tonnes of spent fuel per year. Globally, over 400,000 tonnes of high-level waste sit in storage pools and dry casks, waiting for a permanent solution. Finland’s Onkalo repository and Sweden’s Forsmark site are the only deep geological repositories under construction. At current pace, most countries won’t have permanent storage for decades.

An accelerator-driven system offers a different answer: don’t bury the waste — transmute it. Break the most dangerous long-lived isotopes into shorter-lived or stable ones. Reduce the danger window from 100,000 years to under 300. (For a detailed explanation of ADS physics and the MIT transmutation data, see our earlier article on accelerator-driven transmutation.)

A Proton Beam Aimed at Liquid Metal

CiADS works in four steps. A superconducting linear accelerator generates a beam of protons and drives them to 80% of light speed. The beam slams into a target of liquid lead-bismuth eutectic — a low-melting-point alloy that stays liquid at operating temperatures and efficiently produces neutrons when hit by fast protons.

Spallation — a nuclear reaction in which a high-energy particle (usually a proton) strikes a heavy nucleus and knocks out dozens of neutrons. These neutrons then drive further reactions in the surrounding fuel.

Each proton impact triggers spallation, releasing a shower of neutrons into a surrounding blanket of nuclear fuel and waste. These neutrons slam into long-lived actinides and knock them apart — either splitting them through fission or adding neutrons that shift them along the periodic table into isotopes with half-lives measured in years, not millennia. Both reactions release usable energy. The reactor itself is subcritical: it cannot sustain a chain reaction on its own. Shut off the accelerator, and the nuclear reactions stop within milliseconds. No meltdown scenario. No need for emergency cooling systems.

The facility sits in Huizhou, Guangdong province, run by the Institute of Modern Physics under the Chinese Academy of Sciences. Deputy director He Yuan called it «an internationally recognized ideal approach to nuclear fuel recycling and nuclear waste treatment.»

Three Fronts, One Strategy

CiADS is not China’s only unconventional nuclear bet. It is one piece of a three-pronged strategy for nuclear energy independence.

The second piece arrived in November 2025, when the Shanghai Institute of Applied Physics achieved the world’s first conversion of thorium to uranium-233 fuel in a working reactor. Their TMSR-LF1 — a 2-megawatt thorium molten salt reactor sitting in the Gobi Desert — proved that the thorium fuel cycle works outside of theory.

Thorium fuel cycle — an alternative to the uranium fuel cycle in which thorium-232 absorbs a neutron and transforms into uranium-233, a fissile material that can sustain a chain reaction. Thorium is 3-4 times more abundant than uranium in Earth’s crust.

The third piece is CFR-600, a sodium-cooled fast breeder reactor under construction in Fujian province, designed to produce more plutonium fuel than it consumes.

All three projects serve one strategic purpose: freeing China from dependence on imported uranium. China has modest uranium reserves but large deposits of thorium. If CiADS can burn existing waste stockpiles while TMSR breeds new fuel from thorium, the country’s nuclear fleet could theoretically run for centuries on domestic resources. That is the origin of the «1,000-year energy» headline — not a precise engineering calculation, but a reference to China’s thorium reserves and the Chinese idiom «千年» (qiānnián), which colloquially means «for generations to come.»

Prototype Scale, Gigawatt Ambitions

CiADS is a research facility, not a power plant. Its output is measured in megawatts — enough to validate the physics and engineering, not enough to light a city. The jump from a megawatt-scale prototype to a gigawatt-scale commercial reactor is enormous, comparable to the gap between a laboratory fusion experiment and ITER.

Several hard questions remain unanswered. The accelerator itself consumes significant power. If a substantial fraction of the reactor’s output feeds back into running the accelerator, the system might excel at waste destruction but produce little net electricity. For waste management alone that might be worth it — but the economics depend heavily on how efficiently the beam-to-neutron conversion works at scale.

There is also the proliferation issue. An ADS fuel cycle that processes spent nuclear fuel inevitably handles plutonium and other weapons-usable materials. Safeguards and international monitoring will need to evolve alongside the technology — a concern the IAEA has flagged for all advanced fuel cycle concepts.

Belgium’s MYRRHA project, the closest Western equivalent, has been in development for over 25 years and is still under construction. The Netherlands operates a small experimental setup. The US NEWTON program focuses on improving accelerator components rather than building a complete system. China’s advantage is not necessarily better science — it is the ability to fund, approve, and construct large nuclear infrastructure faster than democratic processes typically allow.

CiADS specifications and timeline are based on reporting from the South China Morning Post, Science and Technology Daily (China), and the Institute of Modern Physics. Independent operational data will only become available after the facility’s planned 2027 startup.

What This Means for the World’s Nuclear Waste

If CiADS works as designed, it demonstrates something that has lived in textbooks and conference slides for years: you can take the most dangerous components of nuclear waste and make them orders of magnitude less hazardous within a human lifetime. That does not solve the politics of nuclear energy. It does not address cost competitiveness with solar and wind. But it removes one of the oldest objections — that nuclear power creates an eternal problem for which no solution exists.

The waste already exists. Over 400,000 tonnes of it, accumulating every year. Whether any country chooses to build ADS reactors at commercial scale will depend on cost, politics, and how fast renewable alternatives mature. But for the first time, the option is no longer hypothetical.

Frequently Asked Questions

Can existing nuclear waste from storage sites be fed into this reactor?

In principle, yes — that is the primary purpose of an ADS. However, spent fuel must first be reprocessed to extract the minor actinides (neptunium, americium, curium) that the reactor is designed to transmute. This reprocessing step is itself complex, expensive, and raises proliferation concerns.

How much of the reactor’s energy goes back into running the accelerator?

This is one of the key unknowns. The accelerator requires substantial power — potentially a significant fraction of the reactor’s output. CiADS is a research facility designed to answer precisely this question. If the energy balance proves unfavorable for net electricity production, the system may still be viable purely as a waste treatment technology.

Is this like fusion — always «20 years away»?

Not quite. Unlike fusion, the individual components of an ADS — proton accelerators, spallation targets, subcritical reactors — all exist and work separately. The challenge is integrating them into a reliable, continuous system at useful scale. CiADS is physically built and scheduled for startup in 2027. The bigger uncertainty is whether it can be scaled from megawatt to gigawatt level for commercial use.

Does this reactor create weapons-grade material?

An ADS fuel cycle handles plutonium as part of the waste treatment process. While the system is designed to consume plutonium rather than produce it, the intermediate processing stages do involve weapons-usable materials. International safeguards and monitoring frameworks will need to be adapted for this technology.

How does this relate to the thorium molten salt reactor China tested in 2025?

CiADS and TMSR-LF1 are complementary parts of China’s nuclear independence strategy. TMSR converts abundant thorium into fissile uranium-233, creating new fuel from domestic resources. CiADS destroys existing nuclear waste, shortening its danger period by orders of magnitude. Together, they aim to close the nuclear fuel cycle — producing energy from thorium while eliminating legacy waste.