China is building a giant laser to generate the energy of the stars, satellite images appear to show

CNN

05-02-2025

Images from space reveal an enormous X-shaped building rising up from rocky terrain in southwestern China. This is a huge nuclear fusion research facility, analysts say, and it could be a sign China is leaping ahead in the quest to harness this futuristic energy source.
It could also mean they are amping up nuclear weapons development.
Decker Eveleth, an analyst at US-based research organization the CNA Corporation, has been among those watching this facility for years. In 2020, a US official released images purporting to show various potential Chinese nuclear locations, including the site near Mianyang in Sichuan province.
At this point, it was basically 'a patch of dirt,' Eveleth told CNN. But after Covid shutdowns were lifted, construction accelerated. The project is described as a 'laser fusion' facility in contract documents obtained by Eveleth and seen by CNN.
If the facility is indeed a laser facility, it will offer a unique way of studying materials in extreme conditions. It allows scientists to create 'pressures that are typically found in the center of stars or in nuclear weapons,' said Brian Appelbe, a research fellow from the Centre for Inertial Fusion Studies at Imperial College London.
Eveleth says the four giant arms shown in the satellite image are 'bays' which will be able to shoot lasers at the tall, central tower, which houses a target chamber containing hydrogen isotopes. The laser energy fuses the hydrogen together to create a burst of energy in a process called ignition.
Nuclear fusion offers the tantalizing prospect of abundant, clean energy without the long-lived radioactive waste problem of nuclear fission, the world's current nuclear energy technology. Countries and companies across the world are in a race to master it.
The US has long been a leader. The National Ignition Facility in California, which also uses laser-ignition technology, made a huge fusion energy breakthrough in 2022. In a world first, NIF scientists achieved a successful nuclear fusion reaction with a net energy gain (although they didn't count the energy needed to power the lasers).
It was a big step forward in the decades-long quest to recreate on Earth the reaction which powers the sun and other stars. But this new facility in China could be a sign China is starting to to edge ahead.
'It signals that they are serious about fusion' said Melanie Windridge, CEO of Fusion Energy Insights, an industry monitoring organization. 'They are being decisive, moving quickly and getting things done.'
Eveleth estimates China's Mianyang research center will be around 50% bigger than the United States' NIF and, once completed, likely the biggest facility of its kind in the world.
Its size could have advantages. A larger laser allows higher pressures and more material can be compressed, potentially increasing the energy achieved from nuclear fusion experiments, Appelbe told CNN. Although, he cautioned, achieving a successful fusion experiment is 'extremely challenging' even with a very large laser.
CNN contacted China's Ministries of National Defense and of Science and Technology for comment but had not heard back at the time of publication.
Experts say the facility also gives China the ability to research nuclear weapons.
China and the US are both parties to the Comprehensive Nuclear Test Ban Treaty, which prohibits nuclear explosions.
The level of energy unleashed by nuclear weapons is very difficult to simulate with computers and other conventional methods. This is where laser-ignition fusion facilities can help, Eveleth said. They can shine high-powered lasers onto various materials to simulate the conditions in the first few microseconds after a nuclear explosion.
'Any country with an NIF-type facility can and probably will be increasing their confidence and improving existing weapons designs,' William Alberque, a nuclear policy analyst at the Henry L. Stimson Centre, told Reuters.
A positive interpretation of the facility is that it provides reassurance China isn't planning any explosive nuclear testing, Eveleth said. But, he added, it could also allow them to develop more sophisticated designs, including smaller nuclear weapons.
Some experts believe the Mianyang site may end being a different kind of fusion facility, a hybrid of fusion and fission.
'If this proves to be true, it is particularly alarming,' said Andrew Holland, chief executive of the Fusion Industry Association. This would be homegrown Chinese tech and 'likely more powerful than anything of that type in Western countries.'
Regardless, the facility 'is clearly part of an ambitious program,' Holland told CNN.
The US is still ahead in the fusion race for now, he added, but 'China is moving fast' and has shown it can move from concept to completion much faster than any government programs.
'It is time to build, it is time to invest,' Holland said. 'If the US and its allies do not, then China will win this race.'