On June 27, two of China's domestically developed superconducting magnets for a nuclear fusion reactor completed technical acceptance and full‑condition parameter tests. Among them, the high‑temperature superconducting central solenoid coil is a key component of a compact fusion experimental device. The device is scheduled to be completed by the end of 2027, and is expected to demonstrate first electricity generation from fusion around 2030.

To mimic the energy‑release mechanism of the sun, the "artificial sun" requires heating fuel to temperatures exceeding 100 million degrees Celsius. However, no material can withstand such extreme heat for extended periods. For decades, scientists have relied primarily on powerful magnetic confinement to "levitate" the plasma, keeping the burning fuel from touching the walls and extinguishing.

Under the current mainstream approach, controlled nuclear fusion uses deuterium – a light atomic nucleus extracted from seawater – as fuel. The fusion energy from one liter of seawater is equivalent to 300 liters of gasoline, producing almost no highly radioactive nuclear waste and zero carbon emissions. The world's oceans contain an estimated 45 trillion tons of deuterium, enough to sustain human development for billions of years at current consumption rates. This is why major developed countries are all focused on "artificial sun" technology.

The magnets that passed the tests are 100% domestically produced, from raw materials and structural design to equipment and manufacturing processes. Costs have also changed: the same superconducting material that once cost 400 yuan (about $59) per meter now costs just 100 yuan.

More importantly, the new coils far exceed previous specifications in weight, size and energy storage capacity, with a single coil rising from 350 tonnes to 580 tonnes. This means the future "artificial sun" will be capable of generating even greater energy.