Challenges in Space-Based Solar Power: Design Challenges, Methods, and a Longitudinal Test for Project Execution

Space agencies and nations think that space-based solar power might contribute to the goal of achieving net-zero carbon emissions by 2050. But “we have to prove this is going to actually be a net gain for the planet”, says Jones.

Although the program is related to a Stanisaw Lem novel, it is not ready for full-scale development. It calls for designing an in-orbit demonstration of the technology, launching it in 2030, developing a small version of a space solar power plant in the mid-2030s, and then scaling it up dramatically. Researchers from the European Space Agency are looking at what it would take to assemble modules of a large solar array while in the middle of the earth’s atmosphere. This way, the structure would remain continuously above a particular point on the ground, regardless of the Earth’s rotation.

China has announced plans to put a megawatt-scale demonstration unit in low-Earth orbit in 2028, before deploying another system to a more distant geosynchronous orbit in 2030. Carpenter says that, with sufficient funding, the first multigigawatt solar power station could be operational by 2040. But despite the excitement, huge technical hurdles remain.

Other projects use different designs. In China, a crown-shaped solar collector is being developed as part of a project by the Chasing the Sun project. Both would require remote assembly by robots in orbit, a still-nascent technology.

Karen Jones, a space economist at theAerospace Corporation in Arlington Virginia, said the engineering behind such systems was incredibly complex. Caltech hopes to side-step this problem by flying its flexible panels in formation, without tethering them together, and using algorithms to correct for any fluctuations in position that affect power transmission. A chemical engineer at the University of Portsmouth, UK, says that whichever design is used, the components would have to be launched weekly.

A Caltech prototype experiment will look at 32 lightweight photovoltaic cells, including low-cost perovskites. “The idea here is to kind of do a longevity test,” says Ali Hajimiri, who co-leads the Caltech project.

Last year, researchers at Xidian University used microwaves to transmit solar power in an experiment on Earth. Using only conventional silicon cells, it achieved an overall efficiency of around 2.4%; the test marked the first time that the entire sequence had been demonstrated in a single system, says Xun Li, a researcher on the project. Caltech will be the first space-based experiment to use microwaves to transmit and receive power, with a width of only 30 centimetres.

Comments on “Does the electromagnetic field pose a threat to humans and animals?” by J. C. Jones, M. B. Saunders et al

The researchers will need to prove that no adverse effects have been found on humans, animals or the environment. Jones thinks that the mobile-wireless industry should lead the way in showing the concerns and not trivialize them.