Governments are not giving up on nuclear fusion making a meaningful contribution to the global decarbonization efforts, despite the technology's obvious challenges.

Last month, for example, the U.K. government pledged £220 million ($283 million) toward getting a fusion power plant up and running by 2040, as part of moves to cut the country’s emissions to net zero by midcentury.

The funding, covering the first five-year development phase of a spherical tokamak for energy production, “will set us on the path to develop and build a commercially viable fusion power plant by 2040, offering clean, safe and carbon-free fuel supplies,” said a government press statement.

The announcement follows a £22 million funding package to create a fusion energy research facility in Rotherham in north England. A 40-strong team at the facility will carry out research led by the U.K. Atomic Energy Authority in partnership with the University of Sheffield Advanced Manufacturing Research Centre and Britain’s Nuclear Advanced Manufacturing Research Centre, the government reported.

Elsewhere in Europe, the European Investment Bank agreed to a €250 million ($277 million) loan as part of a €500 million investment into an Italian test bed within a program designed to produce safe, clean nuclear fusion energy by 2050.

The Divertor Tokamak Test Facility in Frascati, near Rome, will employ 500 scientists and technicians along with 1,000 other staff, according to the bank.

“If we succeed in making a breakthrough in this technology, it could significantly contribute to our efforts to make Europe the first climate-neutral major economy," said European Commissioner Miguel Arias Cañete in the press statement.

Growing momentum worldwide

Events in Europe reflect growing momentum in fusion research worldwide. This month it emerged that the Los Alamos National Laboratory has preparations “well underway” for a novel fusion concept experiment involving plasma guns in a spherical chamber. GTM has identified at least one private U.S. fusion plant developer that is getting ready to make an announcement in the coming weeks.

China, meanwhile, which is generally viewed as having the most ambitious national nuclear fusion program in the world, is working to get power from an experimental reactor by around 2040.

China has already spent around 6 billion yuan ($893 million) on research and has awarded another 6 billion yuan to start building a reactor five years from now, with around 10 years planned for the construction process, Reuters reported in April.

For now, the most advanced fusion program in the world is ITER (which stands for International Thermonuclear Experimental Reactor), a global research effort funded by the European Union, China, India, Japan, Russia, South Korea and the U.S.

ITER is building the world’s largest tokamak, or plasma confinement chamber, in southern France. ITER’s head of communication, Laban Coblentz, said the organization is due to achieve "first plasma," creating a fusion reaction for a few milliseconds, by December 2025.

“The major milestone for any such device is first plasma,” Coblentz said, adding, “65 percent of the total construction work through first plasma is done. If you look at our monthly completion rate, which is 0.6 percent or 0.7 percent, we’re on track despite the fact that it’s an aggressive schedule.”

It's important to note, however, that this is ITER’s third target for first plasma. The group was originally hoping to achieve the milestone in November 2018. In July 2010, it decided to put the first plasma date back to November 2019. In November 2016, the target was moved again, this time to 2025.

And ITER will never deliver fusion energy to the grid, since the project is purely for research purposes. Commercialization of fusion technology will depend on a demonstration project, imaginatively named DEMO, that will be developed once ITER starts delivering results.

Because of this, said Chris Warrick, communications manager for the the U.K. Atomic Energy Authority, realistically, “commercial power plants are expected to come online in the second half of this century.”

Some argue this will be too late for fusion to make a difference in decarbonizing the energy system, even if it is still worth pursuing as a power source in the long term.

Writing in The Conversation last month, Thomas Nicholas of the Culham Centre for Fusion Energy in Oxfordshire, U.K., said: “The world must reach net-zero greenhouse gas emissions by 2050 in order to limit future warming to 1.5 [degrees] C."

“It’s unlikely that commercial fusion power plants will exist in time for that, and even once a first-of-its-kind DEMO power plant is operational, hundreds would still need to be built to seriously dent global emissions.”