Google-Funded Nuclear Fusion Reactor Hits Temperature Way Beyond Sun's Core

Plasma physicists said they have achieved a nuclear fusion reactor temperature of more than 135 million degrees Fahrenheit at the Google-funded Norman reactor in California.

This is many times hotter than the core of the sun, which is a relatively balmy 27 million degrees Fahrenheit, according to NASA.

The temperature was achieved by scientists at TAE Technologies who operate Norman, which was unveiled in 2017 and initially designed to keep plasma stable at 54 million degrees Fahrenheit—though improvements have since been made.

Norman fusion reactor
A TAE Technologies rendering of its Norman fusion reactor. The company is also working towards its next-generation reactor, Copernicus. TAE Technologires

Nuclear fusion is the process of fusing two atomic nuclei together, creating one single heavier nucleus plus energy as a byproduct. It's the same process that powers the sun, where hydrogen atoms are fused into helium atoms under intense heat and pressure.

For decades, scientists have worked to recreate this process artificially on Earth since it promises a power source that is free of greenhouse gas emissions and has the potential to produce even more power than nuclear fission—the process that current nuclear power plants use—while leaving behind less radioactive waste.

Although scientists have achieved fusion, the key hurdle that has never been overcome is sustaining a fusion reaction that produces more power than it requires to keep going. For example, the leading type of nuclear reactor design, the tokamak, uses power-hungry electromagnets in order to keep the reaction in check.

TAE Technologies was founded in 1998 with the purpose of developing commercial fusion power. Its current best effort, Norman, works by heating hydrogen gas to such temperatures that it becomes a plasma—a sort of soup of positively charged particles called ions and negatively charged electrons.

Plasma temperatures are necessary for fusion reactions, but plasma can also be contained by magnetic fields.

Norman therefore works by shooting two clouds of hydrogen plasma together into a central reaction chamber, where it's held in place magnetically and heated and stabilized by neutral beams.

Despite also needing powerful magnets, TAE said its approach was optimal because it uses a type of fuel called hydrogen-boron that is expected to maximize the lifetime of the reactor.

The machine is huge, measuring roughly 80 feet long, 22 feet high, and weighing about 27 metric tons. It consumes up to 750 megawatts of peak power, which TAE said is comparable to a utility-scale power plant.

Google got involved with the company in 2014 in order to apply data science and machine learning to the research, as well as providing investments.

TAE announced the temperature milestone as it closed a $250m funding round. It has now secured a total of $1.2 billion in funding, which will help development for its next fusion reactor model, to be called Copernicus.

"The caliber and interest of our investors validates our significant technical progress and supports our goal to begin commercialization of fusion by the end of this decade," said Michl Binderbauer, CEO of TAE Technologies, in a press release.

"Global electricity demand is growing exponentially, and we have a moral obligation to do our utmost to develop a baseload power solution that is safe, carbon-free, and economically viable."

The sun
A stock illustration depicts a close-up of the sun. Nuclear fusion is the same process that powers our nearest star. ClaudioVentrella/Getty

Update, 07/20/22, 10:25 a.m. ET: The article was updated to add a new image and a new summary.