S21E19 : The Squirt and the Whale

The Simpsons decide to embrace a cheaper, alternate source of energy by erecting a wind turbine in their backyard. But when Homer realizes some of the power is being directed to the local electric company, he decides to remove his home from the grid and becomes completely dependent upon an unreliable source of power. Meanwhile, a storm erupts, trapping a magnificent 150-foot-long blue whale ashore, and Lisa and Homer attempt to help the poor creature.