An orbiting satellite testing the technical feasibility of collecting and transmitting solar energy to Earth in a single day has completed a year-long mission, and researchers hope to take a closer look at the results. .according to Caltech Mission Summary Engineers on the Solar Space Power Demonstrator (SSPD-1) unveiled today believe all three tools on board the 110-pound prototype were a success, and they believe the project is “the future of space solar power.” I believe that it will be useful for drawing. But even if such a project were to be funded, its future could still be decades away.
SSPD-1, which launched aboard SpaceX’s Falcon 9 rocket in early January 2023, included three experiments. First, the Deployable Ultralight Composite Experiment in Orbit (DOLCE) investigated the durability and effectiveness of a lightweight origami-inspired solar panel structure. ALBA (meaning “dawn” in Italian) tested 32 different solar cell designs to determine the best one for space. At the same time, the Microwave Array for Power Transmission Low Earth Orbit Experiment (MAPLE) tested a microwave transmitter intended to transmit solar power collected in orbit to Earth.
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Perhaps most importantly, Successful demonstration of MAPLE This is the first time in history that solar power will be collected by solar cells and transmitted to Earth via a microwave beam. Additionally, over the course of eight months, members of the SSPD-1 team intentionally increased stress testing on his MAPLE, ultimately leading to a reduction in his ability to transmit. The researchers then reproduced the problem in a laboratory environment and ultimately determined that complex electrical and thermal interactions and wear and tear on the individual array components were the culprit.
Ali Hajimiri, co-director of Caltech’s Space Solar Power Project (SSPP) and Bren Professor of Electrical and Medical Engineering, said: announced today The results “have already led to revisions to the design of various elements of MAPLE to maximize long-term performance,” it said.
“Testing in space with SSPD-1 has made our blind spots clearer and given us confidence in our capabilities,” Hajimiri added.
Today’s solar cells used in satellites and other space technologies are 100 times more expensive to manufacture than terrestrial solar cells. Caltech explains that this is primarily due to the cost of adding a protective crystalline layer, known as epitaxial growth. ALMA determined that perovskite solar cells, while a promising design on Earth, exhibit wide variation in performance in space. At the same time, gallium arsenide cells performed consistently well over long periods of time without the need for epitaxial growth.
As for DOLCE, researchers readily acknowledged on Monday that “not everything went as planned.” Originally he planned to deploy it over three to four days, but DOLCE encountered multiple engineering problems, including snagged wiring and jammed mechanical components. Thankfully, the team was able to solve the problem by referencing the on-board camera to mimic the problem in a full-scale lab replica. Despite the headaches, DOLCE’s space tests “proved the robustness of the basic concept,” said Sergio Pellegrino, SSPP co-director and the Joyce and Kent Cresa professors of aerospace and civil engineering. ”.
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But even if SSPD-1 is an overall success, it could still be years before satellite arrays can be used to store solar power efficiently and affordably. . previous estimate Solar power collected in space costs between $1 and $2/kWh, while electricity prices in the United States currently cost less than $0.17/kWh. Material costs must be significantly reduced while maintaining the strength to withstand solar radiation and geomagnetic activity in space.
There are other issues that must be addressed before space-based solar power can contribute to humanity’s sustainable energy infrastructure.as new york times As pointed out last year, the amount of energy that SSPD-1 will transfer through its microwave beams is miniscule compared to the energy needed for daily use, and such an orbital solar array would likely be thousands of feet away. It would need to be as wide as the International Space Station (for reference, the International Space Station) and only 357 feet long. There are also questions about the safety of irradiating the Earth with powerful microwaves and laser beams.
SSPP researchers recognize that all these issues need to be resolved before orbital solar power plants are truly possible. But their recent progress shows that they at least appear to be on a promising path.
