The distribution feeder design dictates how distribution feeder lines are laid out and interconnected to provide service to customers, and there are several options. The simplest feed is the radial feed, which consists of a single line from the substation out to a number of customers. While the lowest cost of the options, radial feeds do suffer from the fact that loss of cable, primary supply, or the transformer will result in loss of service to all customers on that feed who are downstream of the piece of equipment that failed or opened to protect upstream circuits.
Radial circuits must be deenergized to perform routine maintenance and services. For many utilities radial feeds are the standard design due to the low cost, but for portions of the service area that require higher reliability, other designs such as a loop feed or networking may be used.