Living in SCi-Fi movies is living in a Fantasy
The South Koreans are nothing if not ambitious.
There is the little problem of transmitting the power collected in space and getting it to the ground. A tight microwave beam, perhaps? Or the longest transmission wire ever built, stretching from the surface of the earth out to geosynchronous orbit? What about earth shadow, or a total eclipse by the moon of the array?
Reliance on thorium molten-salt reactors seems to be a better all-around answer, but perhaps there is a lot of money in South Korea for these kinds of research grants.
Back to the Future? 😆