Take hydrogen fuel, which has become a hot topic in the industry over the past couple of years. Hydrogen was the fuel for one of the two stages of the Energia carrier rocket – in 1988, Energia launched the Buran spacecraft, a new reusable shuttle, into low-earth orbit. “The Chemical Automatics Design Bureau and the Voronezh Mechanical Plant worked on hydrogen engines for the Energia carrier rocket,” recalls Boris Katorgin, a rocket engine designer who won the Global Energy Prize in 2012. However, apart from the test launch in 1987, that Energia flight remained the only one: in the early 1990s, the Energia-Buran programme was closed.
Space exploration also contributed to solar energy, which is evident from the Soviet lunar program. The Lunokhod 1 spacecraft (1970-1971) used silicon batteries, while Lunokhod 2 (1973) had gallium arsenide panels, less sensitive to heat, but more efficient in absorbing sunlight. The Soviet orbital stations were also marked by innovations: unlike the fixed panels on Salyut 1 (1971), Salyut 4 (1974) used rotary batteries, and their area increased from 28 sq. m up to 60 sq. m. For nearly half a century afterwords, technology has taken a big step forward: in the coming years, the International Space Station (ISS) will be equipped with roll-up soft film panels.
Orbiting solar power projects have seen less progress. By generating electricity from solar panels in outer space, they could send it to Earth in the form of electromagnetic waves, which would then be converted back to electricity. Having begun to develop in the late 1960s, such projects remain on paper – both due to their high cost and technical complexity. They involve not only deploying a power plant in space, but also transferring converted electricity to Earth. In 2015, by announcing the successful testing of a receiver capable of capturing 1.8 kW waves at a distance of 50 metres, the Japanese Aerospace Exploration Agency took a step towards solving these problems.
The Moscow Radio Engineering Institute of the Russian Academy of Sciences and the Chinese Academy of Space Technologies are also looking for solutions. The former has patented the transmission of electricity from an orbital station to Earth, while the latter announced its intention to launch a solar station with a capacity of 2 GW into space by 2050. Given the scope of the idea, this project is unlikely to be the last for the industry.