Any interruption between power generation and the supply of electricity to homes and businesses can cause a power outage. However, the three most common causes are natural causes, human error, and overload. Any interruption between power generation and the supply of electricity to homes can cause a power outage. It can stem from inclement weather conditions, human error, equipment failure, and even animal interference. Scheduled maintenance can also cause a power outage, though this is usually communicated to households in advance by the utility company.