By pursuing two separate technological routes with a similar objective of overcoming the barriers of traditional photovoltaic systems, Japan has become a global leader in advanced solar technology by developing space-based solar power (SBSP) and perovskite solar cells (PSCs).
Such innovations would be a revolution not only in Japan but also worldwide in renewable energy production, even though they come with practical difficulties that need to be taken into account.
Space-Based Solar Power
For space-based solar power systems (SBSP), the idea is to position satellites with large solar panels in geostationary orbit to continuously receive sunlight — without interruption from the atmosphere or time zones — and then send it to Earth via microwaves. At this point, the project is still too experimental to cause concern among the giants of the Dow Jones Industrial Average.
According to the Japanese government’s assessment, SBSP satellites could achieve a capacity utilization rate of 90% or more, whereas typical solar panels on land would achieve only around 15%. This could generate around five to ten times the energy production of ground-based systems.
Space-based solar energy offers notable benefits that cannot be denied: weather and day-night cycles have no impact on it, and it can deliver energy that is far more stable and predictable than that of traditional photovoltaics. Outside Japan, some researchers argue that SBSP could be a significant renewable energy source by the end of the century, thereby making energy cheaper and reducing the need for expensive storage systems.
On the other hand, this strategy has huge technical and economic challenges. The high cost of launching, the intricacy of building and operating giant orbital systems, and the engineering required for efficient microwave transmission to Earth will make it hard to achieve sustainable commercial deployment in the near future. Currently, most demonstrations are limited to tiny experimental satellites with low power outputs, far below the demand of an actual market.
Another concept related to this innovation is perovskite solar cells (PSCs). These are ultra-thin, flexible, and biodegradable panels. Perovskite cells are only a few micrometers thick; they are also lightweight and versatile enough for use on building exteriors, curved surfaces, and other complex structures.
The government has continually backed the development of PSCs by providing financial support and setting a production capacity target of 20 GW (gigawatts) by 2040. The favorable environment created for the renewable energy market also led to a number of IPOs by related companies last year, as seen in the IPO calendar, bringing more advanced technologies and innovation to the market.
The aim is to boost domestic energy security and decrease its dependence on foreign technology. The availability of key raw materials, such as iodine, an ingredient in PSCs, in Japan gives the country a strategic advantage in establishing a supply chain under local industry control.
Notwithstanding, the PSCs still have to overcome significant challenges. Their lifetime is estimated at 5-12 years, compared to 25 years for silicon solar cells, and their costs remain uncompetitive at a mass-production level.
By combining both SBSP and PSCs, Japan is making a bold move to meet its climate and energy security targets. The space-based arrays could eventually be a large-scale, continuous, and land-use-minimal power source, while the perovskite cells bring solar energy closer to urban and industrial consumers.
Besides, these methods carry significant risks: SBSP's high cost and complexity could push the time to realize benefits to decades, and PSCs must address performance and durability issues before their adoption becomes global.
In this way, Japan's long-term commitment to these solar technologies is an example of the world's innovative countries that (if the technology works) would not only massively increase the share of renewables in a carbon-free future but also, of course, necessitate technical breakthroughs and continuous policy support to realize that potential.