Will space-based solar power ever make sense?

Is space-based solar power just an expensive and risky dream? Or is it a viable way to combat climate change? Although transmitting solar power from space to Earth may eventually involve gigawatts of power, the process could be surprisingly safe and cost-effective, according to experts from Space Solar, the European Space Agency and the University of Glasgow.

But we will need to go beyond just display devices and solve a number of engineering challenges if we are to develop this potential.

Space solar power design

Sending solar power from space is nothing new—communications satellites have been beaming solar-generated microwave signals to Earth since the 1960s. But sending useful amounts of energy is a different matter entirely.

“The idea [has] “It’s been around for a little over a century,” said Nicole Cappelen, a deep space exploration scientist at the European Space Agency, in Physics World Podcast“The original concepts were actually science fiction. They’re rooted in science fiction, but since then, there’s been a trend of interest that has come and gone.”

Researchers are studying several designs for space-based solar power. “It’s a very exciting time for us,” says Matteo Cerutti, senior lecturer in space systems engineering at the University of Glasgow. Books in conversation Many designs have been proposed.

The Solaris initiative is exploring two potential technologies, according to Sanjay Vijendran, head of the Solaris initiative at the European Space Agency: one that involves sending microwaves from a station in geostationary orbit to a receiver on Earth, and the other that involves using huge mirrors in lower orbit to reflect sunlight back to solar farms. He said he sees both as potentially valuable solutions. Microwave technology has attracted the most interest and was the main focus of these interviews. It has huge potential, although high-frequency radio waves could also be used.

“We already have a 24/7 clean energy source from space,” Vijendran said. The energy can be transmitted regardless of weather conditions because of the microwave frequency.

“A 1 gigawatt power plant in space is comparable to the five largest solar farms on Earth,” said Andrew Glaister, host of the Physics World podcast. “A 1 gigawatt power plant could power about 875,000 homes for a year.”

But we’re not ready to deploy anything like that. “It would be a huge engineering challenge,” says Caplin. There are a number of physical obstacles to successfully building a solar power plant in space.

Using microwave technology, a solar array for a power plant orbiting the Earth and generating a gigawatt of energy would have to be larger than one square kilometer in size, according to Article about nature “This is 100 times the size of the International Space Station, which took a decade to build,” says senior correspondent Elizabeth Gibney. It will also have to be assembled robotically, because the orbiting facility will be unmanned.

Solar cells must be able to withstand radiation and space debris. They must also be efficient and lightweight, with a power-to-weight ratio 50 times greater than a typical silicon solar cell, Gibney wrote. Reducing the cost of these cells is another factor engineers must consider. Gibney wrote that reducing losses during energy transfer is another challenge. According to the European Space Agency, the energy conversion rate must be improved by 10-15 percent. This requires technological advances.

Space Solar is working on a satellite called CASSIOPeiA, which was published in the journal Physics World. Describe It looks like a spiral staircase, with the photovoltaic panels being the “treads” and the microwave transmitters – rod-shaped dipoles – being the “levers”. It has a spiral shape with no moving parts.

“Our system consists of hundreds of thousands of dinner plate-sized modules,” said Sam Adlin, CEO of SpaceSolar. “Each module contains photovoltaic energy that converts the sun’s energy into direct current electricity.”

“This DC power then powers electronics to transmit power…to Earth from dipole antennas. This power is converted in space into [microwaves] “It is then sent in a coherent beam to the ground where it is received by a rectifier antenna, converted back into electricity, and fed into the grid.”

Robotics technologies for space applications, such as on-orbit assembly, are advancing rapidly, Adelin added.

SPS-ALPHA, another design, has a large solar collector structure that includes many solar reflectors, which are individually movable small reflectors, Cerutti wrote. concentrate Sunlight is directed to separate power generation units, and then transmitted back to Earth by another unit.