A decade ago, Shanghai scientists completed testing of a prototype small nuclear reactor using thorium as fuel and molten salt as the coolant. Now the first commercial power plant using this technology has connected to China’s grid.

Although small by traditional nuclear reactor standards, at 100MW the new plant can power up to 100,000 homes, and more importantly, will serve as baseload stability for solar farms in the area. And because it uses molten salt rather than water for cooling the reactor and heating the steam turbines, the power station can be situated in the desert rather than on the coast.

Thorium is abundant in China, and mildly radioactive in its natural form. It is considered safer than uranium for nuclear energy, as in the case of an accident the molten fuel would simply cool down and solidify, and not escape into the environment. Thorium also can’t be used for nuclear weapons, and China has great plans for offering ‘green’ nuclear power to other countries involved in its ‘Belt and Road’ initiative.

To reach its goal of carbon neutrality by 2060, China has been building solar plants and wind farms at an incredible pace, but needs baseload power to balance the intermittent nature of renewable energy. Hundreds of coal-fired power stations across China have already been shuttered, with more to come in the next decade.

“There’s only so much you can do with lithium batteries,” said Professor Yan of the Shanghai Institute of Applied Physics, who designed the reactor. “We need these small nukes now, more than ever.”

One question remains: Will the harsh, corrosive nature of radioactive molten salt at 1,000°C limit the useful life of the reactor’s piping, or will modern materials be up to the task? Only the future knows!