Herlong Substation: Jacksonville Electric Authority 69 kV Substation

Herlong Substation is an operational electrical substation located in Jacksonville, Florida, United States. It is owned and operated by the Jacksonville Electric Authority (JEA), a major public utility serving the Jacksonville metropolitan area. The substation operates at a voltage of 69 kV, placing it in the medium-voltage range typical for distribution-level infrastructure. As a substation within the JEA network, Herlong Substation plays a role in stepping down transmission voltages for local distribution. The facility operates under the regulatory framework of the North American Electric Reliability Corporation (NERC) and the Federal Energy Regulatory Commission (FERC), which set reliability standards for the bulk power system. In Florida, the Public Service Commission oversees utility operations, ensuring compliance with state regulations. The substation supports the electrical grid for the Herlong area and surrounding communities in Jacksonville. Its operational status contributes to the reliability and stability of the local power supply, serving residential, commercial, and industrial customers. The facility is part of JEA's broader infrastructure to meet the energy demands of a growing urban region.

The substation is located in an urban area of Jacksonville, Florida, a region with a subtropical climate that experiences high humidity, frequent thunderstorms, and occasional hurricanes. These weather conditions pose risks to electrical infrastructure, including potential flooding and wind damage. The facility's design likely incorporates measures to withstand such events, such as elevated equipment and robust structural standards. The surrounding environment includes mixed residential and commercial development, with proximity to natural areas that may require careful management of electromagnetic fields and stormwater runoff.