Man
Rice paddy power comes from a man. One man, in fact. He's running on a big wheel next to the rice paddy and providing all of the power for the rice to grow and be harvested.
だん, なん
おとこ
None
A man can power an entire rice paddy until dawn (だん). Once dawn comes they need a little break, so they nap. But once dawn is over, they're back at it again!