More than a decade ago, the Japanese company Shimizu Corporation presented a futuristic proposal: to build a ring of solar panels around the lunar equator, called Luna Ring.
The idea is to install a 6,800-mile-long belt capable of capturing solar radiation continuously, without depending on weather or darkness.
Energy Context
The project gained relevance after the nuclear disaster at Fukushima Daiichi in 2011, which prompted Japan to seek safer and more sustainable energy alternatives.
According to the company, solar panels on Earth generate only one-twentieth of the energy they could produce in space, where there is no atmosphere, clouds, or night.
The company’s president, Tetsuji Yoshida, stated that if all that energy could be sent to Earth, there would be no need to rely on coal, oil, or biomass.
Operation of the ring with solar panels
The proposal suggests capturing solar energy at the lunar equator, transforming it into electricity, and transporting it to the visible side of the Moon.
From there, it would be converted into laser beams that would travel to Earth, where they would be reconverted into usable electricity. Additionally, the system could produce hydrogen as fuel, moving towards a less fossil-dependent society.
Construction would be carried out by robots controlled from Earth, with occasional support from astronauts.
The main challenge is the high economic cost. Experts like Masanori Komori from the Institute of Energy Economics of Japan point out that the idea is theoretically attractive but too expensive in practice. Although there is no concrete cost estimate, Shimizu claims that the necessary technology is already available.
Renewable Energies in Japan
The country is committed to diversifying its energy sources to ensure energy security, reduce dependence on imported fossil fuels, and achieve carbon neutrality by 2050. With goals for 36-38% of electricity to come from renewables by 2030, Japan positions itself as the third-largest producer of solar energy in the world.
In addition to innovative projects like the Luna Ring, Japan promotes solutions such as floating solar panels, offshore wind energy, wave energy, and osmotic plants, aiming to overcome land limitations and improve grid integration.
The Luna Ring project reflects Japan’s technological ambition and its search for radical energy alternatives. Although its economic viability is uncertain, the proposal opens a debate on how to harness space to generate clean and constant energy in a world that needs to accelerate the transition to renewable sources.
