Beijing sets eyes on space for clean energy

BEIJING: Amid global efforts to replace fossil fuels with clean energy, Chinese scientists and engineers are working on a bright idea — soaking up abundant energy from the sun and then beaming it back to Earth.
Multiple teams in China are currently focused on technologies needed for building and running a space-based solar power facility, which will allow the sun’s energy to be captured nonstop, something that isn’t possible from Earth, said Hou Xinbin, a senior researcher at the China Academy of Space Technology in Beijing and a member of the Committee of Space Solar Power of the Chinese Society of Astronautics.
After collecting solar energy, the space facility will convert it into electromagnetic radiation, such as microwaves, and laser beams and send it wirelessly back to the Earth’s surface. Receiving stations will then turn these electromagnetic waves and laser beams into electricity for distribution to power grids, according to Hou, who is also a member at the Permanent Committee on Space Solar Power of the International Academy of Astronautics. “My colleagues at several domestic institutes and I have proposed a technology demonstration mission to the country’s space community, and are hoping it will happen in the near future,” Hou told China Daily in an exclusive interview last month in Beijing, on the sidelines of an international space industry forum.
“As a key step to verifying the feasibility of space-based solar power generation, we want to make and place into orbit a pair of satellites — a large one that will collect solar power and convert it to microwaves and laser beams, and a smaller one responsible for receiving laser beams. Meanwhile, a ground station will be in charge of receiving the microwaves. The two satellites will form an in-orbit testing system for wireless power transfer,” he said.
According to the scientist, it is quite difficult to beam laser power to Earth, but it is easier to realize the task between satellites in orbit or between a satellite and a celestial body because of the vacuum.
“Realizing laser power transmissions is meaningful in terms of space programs. For instance, a solar power satellite with laser transmission capability can operate in a lunar polar orbit and provide power supply to exploration programs in polar regions on the moon,” he said.
However, a host of technical issues must be solved before any commercially viable solar power project can take shape in space, Hou said.
The challenges include developing high-performance components with acceptable sizes and weights — these cannot be too big or too heavy — and integrating them into a satellite, and also ensuring that the power beams reach ground receiving stations with great accuracy, he said. –The Daily Mail-China Daily news exchange item