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But there is debate in the scientific community around whether the microwave beams will damage communications, human health or the environment.

Yang said the Chinese space station would get involved in a number of critical experiments to bring the space power plant from science fiction to reality. Some external portals on the station were designed to have high-powered electrical equipment plugged in, he said.

However, the generation of a strong electric current and conversion to microwaves will produce excessive heat and many other problems, which are not easy to solve in the space environment.

The space station is an ideal platform for China to evaluate the long-term performance of the new technology and equipment in orbit, Yang said.

The Chinese space scientists also plan to use cargo ships – which are usually left to burn in the atmosphere after a mission – as a basic component to build the solar power plant. Using several robotic arms, Tiangong could join up a number of cargo ships and some extra solar panel units to create a prototype power plant.

This mini power plant, after rising to an orbit 100km above the space station with ion thrusters for safety, would conduct experiments to verify technologies for the full-scale plant, including microwave energy transmission and powering up an allied satellite with a high-energy laser beam, according to a slide show Yang presented to the conference.

China plans to conduct the first space-to-Earth energy transmission experiment over the next few years. A small space power plant that can supply electricity to remote military outposts will be up and running by the 2030s, while commercial power generation is expected to start in the 2050s.

The US Air Force also plans to launch a solar-powered satellite in 2025 that will be capable of producing and sending focused microwave beams from near-Earth orbit.

Some studies have suggested that the microwaves – mostly in the same frequency range as those used by a Wi-fi router – will be safe for humans unless a person stepped into a receiving area.

But how to keep the energy beam aimed at a precise spot on Earth over a distance of tens of thousands of kilometres remains a major challenge, according to scientists involved in these projects.

Some researchers also warned that persistent, intense energy transmission between space and Earth could cause disturbances in the ionosphere that could lead to unexpected impacts on the Earth’s environment.