As you may know the Earth has Tides. The pull of the moon's gravity causes these tides. Even though the moon is much smaller than the sun the moon's pull has a more pronounced affect on the Earth's oceans because it is closer. The moon pulls earths oceans creating a tide. When the moon is closer it is high tide. When it is further away it is low tide. When the tides are high and strong it could be good electricity for some business's use.