NEI Engineering logo
  • Version
  • 7 Download
  • 1.83 MB File Size
  • 1 File Count
  • April 30, 2020 Create Date
  • July 29, 2020 Last Updated

Distributed energy resources (DERs) are sources of electric power that are not commonly connected to a bulk power transmission system but are instead interconnected near the load in the electric power distribution system. Typically, the individual DER unit ratings are less than 10 MVA and include both fossil fuel and renewable generations, as well as energy storage technologies. Because DERs are sited at customer load locations, if applied properly, they can be more efficient than central-station generators because no transmission and distribution system losses occur.

Today's electric system is expected to bring high-quality and reliable power to customer loads. More than a century of development has led to a large interconnected system that brings power from central-station generators via transmission and distribution to end-use customers. Although this system can provide relatively inexpensive power, issues remain such as increasing fuel costs, reducing power plant emissions, and increasing customer needs for higher reliability power. One potential solution to these issues is the use of distributed and renewable energy sources at the distribution level.

The wide variety of DER, however, causes complexity when installed and operated in electrical distribution systems. Traditional radial distribution systems are not designed for two way power flow. Adding additional sources into distribution systems can affect important aspects of system performance such as operations, protection, and system costs. Currently, no industry standard exists to determine the amount and the corresponding location of DER that can be installed on a feeder without causing adverse effects.

In this paper, a novel two-part methodology was developed that ranks utility feeders for the best candidates for DER systems and then optimizes the placement and sizing of DER on electrical distribution feeders based on technical and economic considerations. The full methodology quantifies the factors that influence the performance and costs of the electrical distribution system and the characteristics of the DER. This paper will be specifically useful to electric power utilities and end-use customers wanting to site DER systems.

This paper, a sequel to paper, describes an analytical methodology to evaluate candidate feeders for implementing DER based on peak-load reduction, capacity improvement, load-generation correlation, and expected feeder load growth.

Optimum Sizing and Placement of Distributed and Renewable Energy Sources in Electric Power Distribution Systems