Beaming the energy

The possibilities of wireless power transfer are being pushed to their current limits – and beyond – for space-based solar power (SBSP). The University’s Next Generation Wireless research group is harnessing its expertise to support this.

The precise beaming of solar energy from space to Earth is crucial to the success of SBSP. All that energy from the sun must be sent wirelessly to a ‘rectenna’, or rectifying antenna, on Earth.

This is done by converting the harnessed energy into RF microwave radiation, which is beamed to the rectenna, converted into direct current electricity and fed into the grid.

But the accuracy required to ensure the beam lands in the right spot is critical, requiring a high-efficiency beam alignment for the wireless power transfer system, as well as target-detecting technology for high beam efficiency. Dr Mohammed El-Hajjar, Associate Professor in the Next Generation Wireless research group, is involved with the Space Energy Initiative focusing on the beam steering aspect of SBSP. He said: “We need accurate beam alignment and tracking to maximise the transmitted energy.”

Regular communication is necessary between the ground station and the base station, which is in geosynchronous equatorial orbit, 35,786 kilometres above the equator, to ensure beam accuracy.

“Efficient wireless communications are needed between the ground station and the SBSP station in order to maintain accurate energy transfer,” explained Dr El-Hajjar. “There will be regular interaction between the ground station and base station.”

The finer details of how this will work are still being researched. Watch this space!