Solar energy has always been an important part of human clean energy. We have laid a lot of sunlight collecting panels on the solar field, and many people use rectangular roof decorations to power their houses.
But this wonderful power supply has a caveat. Solar panels cannot collect energy at night. In order to work at maximum efficiency, they need as much sunlight as possible. Therefore, in order to maximize the performance of these sun catchers, researchers are developing a plan to send them to a place where the sun never sets: outer space.
Theoretically, if a pile of solar panels are sent into orbit, they can absorb sunlight and store large amounts of electricity even on the most foggy days and darkest nights. If this energy is transmitted wirelessly to the earth, our planet can breathe renewable clean energy 24/7.
In the context of the worsening climate crisis, the success of space solar may be more important than ever. As world leaders gathered in Glasgow, Scotland to participate in the COP26 summit, climate conditions are now the focus of attention. The summit has been called the “world’s best last chance” to control the crisis.
CNET Science highlights some future strategies aimed at helping countries reduce human carbon emissions. Next-generation technologies like space solar cannot solve our climate problems — we still need to quickly decarbonize our energy system — but green innovation can help achieve the goal of the Paris Agreement: to limit global warming to a far lower level From 2 to the end of this century, degrees Celsius (3.6 degrees Fahrenheit).
For decades, space solar has been in the minds of science fiction fans and scientists.
In the early 1900s, Russian scientist and mathematician Konstantin Tsiolkovsky (Konstantin Tsiolkovsky) was steadily introducing a series of futuristic designs that envisioned human technology beyond the earth. He is responsible for summoning things like space elevators, steerable rockets, and space solar power, you guessed it.
Since Bell Labs invented the first concrete “solar panel” in the 1950s, international scientists have been working hard to make Tsiolkovsky’s science fiction fantasy a reality. They include Japanese researchers, the U.S. military, and the team leading the space solar power project at the California Institute of Technology.
The project’s senior research scientist Michael Kelzenberg said that space solar “was extensively studied in the late 1960s and 1970s, a bit like the heyday of the Apollo program.”
Unfortunately, due to the weight and volume of the material, the technology of that era was not advanced enough to achieve this feat economically and efficiently. Without breaking the bank, it is very difficult to send classic solar panels to space via rockets.
“The unique and defining characteristic of the Caltech method is its focus on reducing component mass by a factor of 10 to 100,” said Harry Atwater, the project’s lead researcher. “This is essential to reduce manufacturing and launch costs to make space solar energy economical.”
The Caltech team did not push traditional solar panels into space, but instead advocated a new type of solar panels that were lighter, more compact, and foldable. They suggested sending a large number of ventilated miniature solar panels similar to tiles into the track.
Each individual tile has everything it needs, such as photovoltaic power generation, to collect solar energy. When connected in space, these small cubes are essentially a huge renewable energy mine floating around the earth.
Although the team has been working on a series of composite materials to create the ideal ultra-light structure, some are actually less efficient than Earth’s solar panels. But Kelzenberg pointed out that in space, “effectiveness” has acquired a new meaning.
“The increase in efficiency does come from the fact that by placing them in space, they can get plenty of strong sunlight because the sunlight does not have to pass through the atmosphere,” he said. “They also spend most of the time in the sun 24 hours a day.”
When sunlight shines on these panels, they will absorb bunches of direct current or DC energy. In the team’s mechanism, this energy is converted to radio frequencies. The next step is to bring this power to the earth.
According to the team, this will happen through microwave radiation. Radio frequency energy will be emitted onto our planet, reminiscent of solar fields in the desert. However, these areas will contain receivers with antennas to collect the collected energy instead of the usual solar panels.
It is basically wireless energy transmission, which is the famous hint of Nikola Tesla in the late 19th century.
Kelzenberg said the use of this radiation allows the system to operate in rain and fog, at night and during mild storms, with the risk of interruption only in the worst weather. However, a question often raised about wireless radiation patterns is whether they will adversely affect vegetation or land characteristics.
“The power density received on the earth is equivalent to the power density in sunny days,” he explained. “In this regard, the space solar system can be designed to be cost-effective and safe.”
Kelzenberg said that as an additional safety precaution, familiar measures can be taken, such as blocking the receiving area. Cell phone towers that use similar forms of wave communication have the same effect.
After the receivers on Earth obtain energy in the form of radio frequency, they will work with the ground station to convert it back to DC energy, and then convert it to alternating current or alternating current, and feed it into the utility grid, Atwater said.
This is a complicated process, but the last point, AC power, is the conventional old electricity that charges your iPhone through your home socket and provides life to your laptop. Look.
“Our first space flight demonstrating solar module technology in space is now scheduled to take place on a commercial spacecraft by the end of 2022,” Atwater said.
Although the team will not launch a real deal, they will conduct an experiment to prove the feasibility of these technologies on a smaller scale. This would be a temporary and simpler form of the invention. They will even send some solar cells that have never seen a vacuum in space before.
Not only can it help power remote areas and balance the grid to prevent power outages, it can also deliver energy for mining operations on other planets.
“Space solar can be deployed to remote areas on the earth where there is no existing utility grid; it can also generate baseload power on the moon or Mars through a similar orbital power generation scheme and launch it to the surface,” Atwater explained.
The most important thing is that human beings can use 24/7 solar energy to generate enough energy to meet the climbing needs of our planet, and can even replace nuclear or coal power. “Unlike solar panels on Earth, it represents a continuously available’base load’ power source,” Atwater said.
Kelzenberg added, “This is why we think it can play an important role in achieving a fully carbon-neutral grid in the future.”
Of course, there is still a long way to go. Even if the team’s 2022 experiment is successful, it still needs to consider manufacturing costs and legal issues that occupy orbital space (there may be government restrictions). Questions surrounding the practicality of replacing known power grids with space solar power plants will also continue to exist.
“I think we can certainly agree that the cost of obtaining a cheap solar panel and putting it on the ground will be much lower than the cost of launching it into space,” Kelzenberg said. “But the real advantage of space solar is the ability to provide solar energy day and night.”