Here are some things to think about for plotting out your story:
What would you do if you wake up late and the power is out? How do you normally react when the power is out? What would make you realize that the power is out? If you have to get to work, do you have an electric car that's low because it couldn't charge? What are some problems that would arise from the power outage and you being late? How can you drag moments out to make the story longer to fit requirements?