After aliens attack in 2199, the Earth secretly builds a massive spaceship inside the ruins of the gigantic Japanese battleship Yamato which lies exposed at the former bottom of the ocean location where she was sunk in World War II. This becomes the "Space Battleship Yamato" for which the story is titled. The new ship gets a space warp drive, called the "wave motion engine", and a new, incredibly powerful weapon at the bow called the "Wave Motion Gun".

The actual WW2 Yamato class battleship weighed about 72,000 long tons fully loaded. It was 263 meters long and 39 meters wide. If every surface was covered with solar cells then there would be about 20,000 square meters of exposed solar cells. The solar cells on the side would be gathering power since there would be sunlight reflected from the water plus the angled light from the sun. On a sunny day there would be about 600 watts per square meter. This would generate about 12 megawatts at about high noon.

EMDrive is highly controversial. It is a potential propellantless propulsion. NASA tests of EMdrive performance seem to indicate 1.2 millinewtons per kilowatt.