From Ohio History Central
Brownouts occur when power plants fail to produce enough electricity to meet demand. Because there is a greater demand for electricity than the amount being produced, homes and businesses will not receive as much electricity as they might need to operate electrical items. Brownouts can damage numerous types of electrical equipment, especially computers.
Brownouts have occurred in Ohio. Due to Ohio's large population and numerous factories, energy usage in the state is very high. In 1999, Ohio was the third largest energy consuming state in the United States. Brownouts in Ohio usually occur in the summertime, when temperatures are very hot. Air-conditioning units require a great deal of energy, oftentimes exceeding the supply of available electricity.