by JIANG Xi

Shanghai is rapidly emerging as China's main hub for commercial nuclear fusion, as private capital pours into a sector once dominated by state-led research.

Shanghai-based fusion startup Startorus Fusion said on Thursday it had completed a 500 million yuan (about US$73 million) Series A+ funding round, pushing its valuation above US$1 billion and making it one of China's latest deep-tech unicorns.

The financing comes just months after the company raised 1 billion yuan in a Series A round earlier this year, one of the largest single fundraising rounds by a private fusion company in China.

The latest investors included venture capital firms, industrial investors and Shanghai state-backed funds, underscoring growing investor interest in commercial fusion as countries race to develop next-generation energy technologies.

Fusion — the process that powers the sun — has long been viewed as a potential source of near-limitless clean energy, though commercial viability remains years away. Globally, private fusion companies have attracted billions of dollars in recent years as advances in superconducting magnets, computing and plasma control revive hopes for commercialization.

Shanghai is increasingly positioning itself at the center of China's fusion ambitions. The city has brought together state-backed fusion groups, private reactor developers and suppliers specializing in superconducting materials, magnets and advanced power systems, forming one of the country's most concentrated fusion industry clusters.

Alongside Startorus Fusion, Shanghai is home to several other fusion startups pursuing different technical approaches, including Energy Singularity and NovaFusionX. Investors have continued to pour funding into the sector this year despite broader weakness in venture capital markets.

Startorus Fusion was founded in 2021 to commercialize fusion research originating from Tsinghua University and focuses on spherical tokamaks, a compact variant of the tokamak reactor design widely used in fusion research.

Tokamaks use powerful magnetic fields to confine superheated plasma inside a doughnut-shaped chamber to trigger fusion reactions. Developers of spherical tokamaks believe the design could reduce reactor size and cost while maintaining strong plasma performance.

The company is currently developing multiple generations of experimental devices. Its next major system, known as NTST, is expected to begin installation soon at a new research base in Shanghai's Jiading district.

The facility will support testing of key technologies for the company's future reactor, CTRFR-1, including high-temperature superconducting magnets, cooling systems and AI-assisted plasma control.

Startorus Fusion said it aims to achieve Q>1 around 2028 — a milestone where a fusion device generates more energy than is required to sustain the reaction — before moving toward a commercial demonstration reactor in the early 2030s.

The company said it has already developed full-process manufacturing capabilities for high-temperature superconducting magnets, one of the most critical and technically demanding components in fusion systems.

Beyond reactor development, the startup is also commercializing fusion-related electronics and power-control equipment through a subsidiary, generating early revenue from research institutions and industrial customers.