Each ship generates about 3.3 GW of electrity (enough to power continuously nearly three time-travelling DeLoreans from Back to the Future), i.e., 146.5 GW overall. It has two nuclear reactors and costs about $10.44 billion. Conveniently, it weighs about the same as the Allure of the Seas and is of a similar size and volume.
Our second reference point is the Gerald R. Thus we can estimate its weight as 44.4 x 100 million = 4.44 billion kilograms. Hence the Imperial Star Destroyer is approximately 44.4 times the volume of the Allure of the Seas. If you look at a picture of the ship and consider that cruise liners are fairly boxy, we can approximate its volume as 360 x 55 x 60 = 1.188 million cubic meters.
The Allure of the Seasis 360 meters long, 60.5 meters at maximum width (47 meters at waterline), and 81.3 meters at maxmium overall height. Ships are a good analogy because they need to be light and strong to transport lots of stuff fuel-efficiently. Our first reference point is the world's largest cruise liner, the Allure of the Seas.
