Scientists continue to search for clean and sustainable energy sources. One of the promising areas in this activity is the development of technologies that will make it possible to capture solar energy directly in space and then transmit it to Earth. Scientists from the California Institute of Technology (Caltech) have achieved some success in this, who managed to collect energy using an orbital satellite and transmit it to Earth.
Image source: Mmdi/Getty Images
We are talking about the Space Solar Power Demonstration (SSPD-1) mission, which is being implemented by a team of scientists from the Space Solar Power Project (SSPP) from Caltech in collaboration with Indie Semiconductor Inc., NASA’s Jet Propulsion Laboratory (JPL), Amazon Web Services and the startup GuRu Wireless, which is one of the divisions of Caltech. The joint activity led to the fact that scientists were able to collect some energy in Earth’s orbit and then transfer it to the surface of our planet, which can be considered a serious achievement. Detailed information about the work done was presented in article researchers, which was published in arXiv.
On Earth, people have learned to use sunlight to generate energy, but even the most advanced technologies have their drawbacks. For example, on a cloudy rainy day, the power of a solar panel can drop by 25%, and they cannot generate energy at night. At the same time, solar panels placed in orbit can continuously generate energy if they are oriented in such a way that they are always exposed to sunlight. What remains for scientists is to develop a reliable way to transfer energy from orbit to Earth, where it could be used to power businesses, homes and more.
MAPLE apparatus / Image source: Ayling Et Al/ArXiv
The scientists’ experiment was made possible thanks to the Microwave Array for Power-transfer Low-orbit Experiment (MAPLE) device, which was used to transfer energy from space to Earth. It is designed as a small 6U CubeSat and is capable of receiving solar energy collected using photovoltaic cells. MAPLE then deployed rectifying antenna arrays to convert solar energy into radio frequency. After this, a beam of radio frequency energy was synthesized and transmitted to Earth. The equipment for receiving and converting the signal to direct current, as well as for tracking MAPLE, is located on the roof of Moore’s laboratory at Caltech.
The mission began on January 3, 2023, when the research vehicle was delivered into low Earth orbit using a SpaceX Falcon 9 launch vehicle. Exactly two months later, scientists began experimenting with MAPLE and as a result, the mission was considered a success. In the future, the researchers plan to create a constellation of satellites such as SPPD-1, which will be able to transmit energy to Earth to supply 10 thousand households. However, this is still a long way off, since at the moment MAPLE captures from 175 to 251 mW of energy in space at a time, and only 1 mW of energy has reached the ground station.
Shambhu Kumar is a science communicator, making complex scientific topics accessible to all. His articles explore breakthroughs in various scientific disciplines, from space exploration to cutting-edge research.
