Physics - the Centrifuge Problem

After so many mathematics and game theory puzzles, I've finally got some good physics puzzle to solve! I must say, although the world seems to be full of problems and entirely perplexing situations, it is very difficult to find a good mental puzzle. Random surfing on internet would only return either very complex and uninteresting puzzles (each of which has an obvious method of solving - which is so cumbersome that you won't bother solving it!) or childish puzzles ("Where is the missing coin?" - if you ever find it, keep it!!) or different versions of Einstein's puzzle (Which lady is which man's wife and who is her son's father, etc. - should be called Ekta Kapoor's puzzle :-) )

Finally, I got this puzzle on the internet. Let's see what you can make out of it.

You've got a disk that rotates on its axis. Let's say it is powered by electricity. The disk has got a vertical nail somewhere on its surface. Now, take a coin with a hole at its centre. Place the coin on the disk such that the nail fits in the hole. The coin is now lying loosely on the surface of the disk with the nail through the hole in it. Now in trial 1, rotate the disk with a particular angular velocity. In trial 2, paste the coin to the surface of the disk using a massless glue; and rotate the disk with the same angular velocity.

Now, initially, both the systems are at rest. We use electricity to set each system (each trial) in motion. After that, these would move on their own. Which one of these systems will consume more electricity?

The problem basically compares the energy required to move objects with some freely-moving, loosely fitted parts on them, with the energy required to move objects with fixed immovable parts on them. I really do not know the official solution of this problem, but you can find my version of the solution here:

Solution