Renaissance Fusion raises $16.4 million to develop nuclear fusion technology in Europe • TechCrunch

Meet Renaissance Fusion, a Grenoble startup that has been working on nuclear fusion for two years. The company recently raised $16.4 million (€15 million) in funding in a funding round led by Lowercarbon Capital.

Several European investors also participated in the round, such as HCVC, Positron Ventures and Norssken.

“We are proud to support Francesco Volpe and his team in the emergence and industrialization in France and Europe of a breakthrough solution in energy production and distribution technologies. Grenoble is a highly strategic location that allows them to benefit from an environment favorable to the development of nuclear energy, a strong ecosystem like the CEA, and an unrivaled talent pool,” said Alexis Houssou, Founder and Managing Partner of HCVC, in a statement.

Unlike most tokamak-based nuclear fusion experiments, Renaissance Fusion works on a stellarator reactor. The company is well aware that the road is long and windy as it expects to be able to ship a small nuclear fusion reactor with a capacity of 1 GW in the 2030s. It would not operate the power plants directly. Instead, the company would sell its reactors to plant builders and operators.

“We have some pretty unique technology,” Francesco Volpe, founder of Renaissance Fusion, told me. Instead of designing complicated three-dimensional coils to generate a magnetic field, Renaissance Fusion greatly simplifies this process by drawing tracks on a cylinder.

After some calculations based on the magnetic field you wish to generate, the team can determine the shape of the coils you need. The cylinder rotates around an axis while a device moves from left to right to engrave tracks with a laser on the surface of the cylinder.

The cylinder blocks are then combined to form a reactor. This modularity should help with shipping and logistics. As for the neutrons emitted by the nuclear reaction inside the cylinder, Renaissance Fusion wants to use liquid lithium to create thick walls that separate the plasma from the outside world.

“We inject a layer of liquid metal. It circulates inside the cylinder and then it is extracted from below. It is thick enough to absorb the majority of neutrons,” Volpe said.

This liquid metal is also used to extract heat from the Stellarator, which can be used to create steam, which can be used to power turbines, which can be used to generate electricity.

Picture credits: Renaissance Fusion /

According to the founder of the startup, Renaissance Fusion is quite innovative with its use of liquid metal. “We’re the only one in commercial fusion where liquid lithium faces plasma,” Volpe said.

At present, the company can create walls from liquid lithium with a thickness of 1 centimeter. It will take many iterations before it can be used in nuclear fusion as Renaissance Fusion estimates that it would need a thickness of 30 to 40 centimeters.

The company is already thinking about commercial applications that could see the light of day before the 2030s. For example, Volpe thinks Renaissane Fusion’s coil-patterning technology could be used for MRI and energy storage. “Anytime you need a strong magnetic field, large volume and high precision,” he said.

With today’s funding round, Renaissance Fusion plans to triple the size of its team to 60 people by the end of 2023. In many ways, this is still just the beginning of Renaissance Fusion. So let’s see how that plays out in the years to come.