Energy from space flowed to Earth. Scientists managed to create a power plant in orbit

Scientists from the California Institute of Technology (Caltech) on the effects of the completed (one-year-long) Space Solar Power Demonstrator (SSPD-1) mission. This is an experimental satellite launched in January 2023, which was supposed to prove that it is possible to produce electricity from photovoltaic cells in space and send it to Earth.

Three experiments completed successfully. Electricity from space flowed to Earth

The SSPD-1 mission consisted of three experiments whose aim was to test the possibility of producing a significant amount of energy from photovoltaic cells, effectively sending it to Earth and placing a large power plant in space. The aim of the first experiment (DOLCE – Deployable on-Orbit ultraLight Composite Experiment) was to design a solar power plant structure measuring 1.8 by 1.8 meters, which – when deployed in space – will be able to reach dimensions of the order of kilometers – explain the scientists.

As part of the next experiment (ALBA), researchers tested 32 different types of photovoltaic cells in space, assessing their ability to operate smoothly in extreme space conditions. In turn, MAPLE (Microwave Array for Power-transfer Low-orbit Experiment) is a set of light transmitters operating on microwave waves, the aim of which is to test the possibility of transmitting a focused beam of energy from orbit to Earth.

Scientists from Caltech emphasize that all three experiments were successful, although not everything went according to plan. In the initial phase of the DOLCE experiment, the team had trouble disassembling the structure, but fortunately the cause was identified and the problem was solved. Researchers emphasize that such mistakes during tests allow you to collect many valuable tips that can be used in subsequent missions.

In June, electricity from space flowed to Earth. This is proof that the idea can be implemented

Researchers also tested the performance of three brand new ultra-light solar cells that have never been tested in space before. The team emphasizes that the production of solar cells currently used in space is as much as 100 times more expensive than typical panels for operation on the Earth’s surface. However, scientists have learned how to produce cells that are low-mass and resistant to space conditions at a relatively low cost.

The breakthrough moment of the mission took place in June 2023, when the MAPLE experiment managed to transmit energy from orbit to a receiver on the planet’s surface for the first time using a beam of microwave radiation. The technology had previously been tested on Earth, but the June test showed that it could actually work in orbit as well. This makes the idea of ​​building solar power plants in space to send energy to consumers on Earth feasible.

It’s not that we don’t have solar panels in space. Solar panels are used, for example, to power the International Space Station. However, in order to carry out into space and unfold sufficiently large systems [ogniw fotowoltaicznych – red.]To provide the Earth with a significant amount of energy, SSPP must design and create solar energy transmission systems that are ultra-light, cheap, flexible and easy to implement.

– said Harry Atwater, professor of applied physics and one of the main researchers of the Space Solar Power project, quoted in the university’s announcement.

Energy from space is just around the corner? There is still a long way to go before practical use

The possibility of installing solar farms in space will potentially solve the biggest problem of this source of clean electricity. Appropriate placement of cells will allow energy to be produced and transmitted to Earth 24 hours a day and regardless of atmospheric conditions on the surface. However, there is a long way to the potential use of the technology in the practical extraction of cheap electricity from orbit.

So far, we are dealing with the first experiments in orbit, the results of which are pleasing to researchers, but still do not allow for efficient and cheap (comparable to solar energy on Earth) production and transmission of energy to the planet’s surface. For now, it is not even known when the first solar power plants can be expected in space.

Solar energy emitted from space at commercial rates and illuminating the globe is still a prospect for the future. However, this key mission showed that this should be an achievable future

– said Thomas F. Rosenbaum, president of Caltech.

The future of the project will also depend largely on the financing of further work. The Space Solar Power project conducted by researchers from Caltech was financed mainly by the American billionaire Donald Bren, who donated USD 100 million for this purpose, and the American company Northrop Grumman Corporation, which donated USD 12.5 million to the university.