When the power comes back on, it is still dark in the overhead shot. In the following scene where the people are leaving the firehouse, it is broad daylight.
When Severide asks Katie "What did Otis do?", he holds her head/neck in his hands. However, in the next shot, his hands are on her arms.
A large portion of the city is shown being blacked out after one transformer on a residential street is knocked down. In fact, this would affect only a small portion of the customers on that street and adjoining ones, not the large area- described by one character as half the city. To blackout an area such as the one shown, a power substation would need to fail.
The three concerned parties are discussing making improvements to Molly's bar, all of which would require money being spent. They each lobby Shay to support their idea. When Shay says what she wants to do, it is a lesbian night, which would not cost money.