Factual error: In order to be electrocuted you need to connect a high voltage to a low voltage. Touching a power line does not get you electrocuted unless you make contact with the ground. So electrocuting the locusts by making them fly against a powerline can not work because they are not 'grounded'.
Continuity mistake: When Maddie and the others are trapped in the silo, there are a lot of locusts that have landed on the structure, but there is also a huge number of locusts flying through the air all around. After they electrocute the locusts, there's not a single live locust to be seen anywhere, even though all the insects that were not directly on top of the metal building should have survived.
Factual error: Peter is standing next to his daughter's hospital bed, talking on his cell phone to the meteorologist, and none of the hospital employees that walk past him tell him to turn off the phone. Everyone knows that cell phone use is not permitted in hospitals; as on planes, it's thought they can cause vital equipment to malfunction.