The US military space plane is being used to test the best ways to harvest solar energy to transfer power from Earth orbit.
In mid-March, the last secret mission of the US space forces took place. X-37B robotic space plane flew 300 days in low-earth orbit.
Most of the space drone’s missions in this mission, known as the Orbital Test Vehicle-6 (OTV-6), are kept secret. However, one notable study that this ship is conducting is Photoelectric radio frequency antenna module, flight experiment, or PRAM-FX.
US military’s secret space plane X-37B: 6 surprising facts
PRAM-FX is a Marine Research Laboratory (NRL) experiment that investigates the conversion of solar energy into radio frequency (RF) microwave energy. PRAM-FX is a 12 “(30.5 centimeters) square tile that collects solar energy and converts it into radio frequency energy.
Paul Jaffe, Head of Power and Space Solar Power Innovation Portfolio at NRL, said PRAM-FX does not transmit microwave power anywhere. Rather, the experiment evaluates the efficiency of converting sunlight into a microwave. According to him, it is necessary to measure how the PRAM works in terms of efficiency as well as in terms of thermal performance.
Preliminary results
This cosmic challenge is relatively simple. But PRAM-FX is helping to move towards a more ambitious goal of absorbing solar energy and transmitting it to the energy-intensive Earth.
The first preliminary results of PRAM-FX aboard the OTV-6 were published in January as part of a review article co-authored with Jaffe in the Journal of Microwaves of the Institute of Electrical and Electronic Engineers (IEEE).
“While these results are preliminary, they compare favorably with the performance documented in ground tests, which also showed an overall module efficiency of 8%. As the experiment continues, a complete picture of the module’s characteristics under various lighting conditions and temperatures in the space environment will be obtained. be disclosed, “the IEEE document says.
PRAM-FX is a key orbital test for space-based solar architecture. But what’s next?
Connected: How the secret X-37B spaceplane works (infographic)
Step by step
The United States Air Force Research Laboratory (AFRL) has developed a major demonstration project that aims to transfer energy collected in space to expeditionary forces on Earth. This project is called Space Demonstrations and Solar Supplemental Research (SSPIDR).
As stated in the IEEE document, SSPIDR demos include experiments called Arachne, SPINDLE, and SPIRRAL.
“Arachne will be the world’s first space-to-earth demonstration of a modular solar-to-HF panel with on-site surface shape measurement to optimize beamforming. The solar-to-RF panel technology is designed to scale to very large openings and to support high-volume, low-cost manufacturing, ”the document says.
Arache is scheduled to fly in 2024. AFRL received the first hardware component of the Arachne spacecraft flight from Northrop Grumman last December.
SPINDLE will test the deployment of a sub-scale version of the operating system in orbit. The document says SPIRRAL “will test thermal management approaches to ensure a durable and high-performance system.”
If all goes according to plan, SPIRRAL will launch in 2023 as part of the International Space Station (MISS-E) Experimental Materials Complex. MISS-E is an orbital platform from the Alpha Space Test and Research Alliance designed for external deployment on International space station…
Boundless and Sustainable Energy
John Mankins is a longtime proponent of the spread of space energy and author of The Case for Cosmic Solar Power (Virginia Edition Publishing, 2014). He worked at NASA for 25 years and is now President of Artemis Innovation Management Solutions, LLC.
Space solar power has the potential to change the future of humanity in space and could provide a new source of near-limitless and sustainable energy for markets around the world. So, Mankins said, why don’t we go into this kind of technology?
“There are many new players in wireless power transmission — both radio frequency and laser — in the US and abroad,” Mankins told Space.com. “China has just approved the formation of a national-level committee on space solar energy and wireless power transmission, which will add value to their already strong research and development program.”
Mankins also points to the United Kingdom. The country is currently exploring the possibility of joining the international space solar energy and wireless transmission community, and the main assessment will be completed in January this year.
Looking beyond LandNew applications for wireless power transmission are emerging when planning exploration of the moon, where ice deposits are located exclusively in permanently shaded regions at temperatures around minus 390 degrees Fahrenheit (minus 234 degrees Celsius), Mankins said.
“But mining and processing water ice to produce useful materials will require hundreds of kilowatts of energy, such as fuel… Wireless power could be the answer to that question, ”suggested Mankins.
Expensive asset
Overall, the outlook looks encouraging that cosmic ray energy can be a highly valued asset in the commercial sector.
Technology may have a future similar to that of the United States. satellite navigation systemwhich started out as a military asset and then moved on to technology used around the world, experts say. Perhaps in the future, solar radiation will be widely used, providing an abundance of solar energy everywhere, regardless of local weather, time of day or latitude.
By the way, for the history buffs: Nikola Tesla created the concept of large-scale transmission of energy through free space at the turn of the 20th century!
Leonard David is the author of Lunar Dash: The New Space Race, which was published by National Geographic in May 2019. A longtime author of Space.com, David has written about the space industry for over five decades. Follow us on Twitter @Spacedotcom and on Facebook. This version of the story is posted on Space.com.