The Electric Power Research Institute (EPRI) and the U.S. Department of Energy's National Renewable Energy Laboratory (NREL) have developed and tested a standard messaging platform for distributed energy resources (DER) -- solar panels, wind turbines, microgrids and battery storage -- that use smart inverters to connect to the grid. The new system, called a Distributed Energy Resource Management System (DERMS), would enable DER to "communicate" with other systems, providing information about demand, supply, and use of electricity. The DERMS system also provides a way for grid operators to more effectively manage the generation and dispatch of electricity.
"DERMS represents a significant development toward fully accommodating and integrating distributed resources in the planning and operations of the electric system,†said Mark McGranaghan, vice president of Power Delivery & Energy Utilization at EPRI. “It will facilitate making the best and fullest use of both central and distributed energy resources."
"In the near future, DERMS will allow operators to communicate with and control large numbers of emerging resources on the distribution system to help the grid adjust to the peaks and valleys of demand and supply,†said Bryan Palmintier, senior research engineer in Energy Systems Integration at NREL. “However, achieving this vision will require DERMS to work seamlessly with other utility systems."
The research and development effort was the culmination of several years of coordinated work with numerous industry stakeholders. It builds on an earlier EPRI initiative that developed a technical basis for smart inverter standards, which resulted in the creation of the International Electrotechnical Commission (IEC) standard IEC 61850-90-7. This IEC standard, which provides a common set of smart inverter functions, set the stage for the next level of development -- aggregating messages from the inverters.
In 2013 EPRI convened stakeholders to identify the most important uses for managing the communication to groups of DER. This resulted in a set of specific experiments to test how DERMS could work to create, maintain, monitor, forecast and dispatch groups of DER.
Working with the Common Information Model (CIM) and MultiSpeakTM standards communities, the team developed a set of web service messages to instruct the groups of DERMS in each use case. Using these messages, the DERMS system manages the enterprise communications using CIM/MultiSpeakTM while converting the messages to the individual DER using IEC 61850.
In 2014, a test procedure was developed and the EPRI Semantic Test Harness -- a tool for testing web-service messages -- was updated to support the testing of these new messages. A workshop was held at NREL in Golden, Colo., which proved the capability of an architecturally agnostic DERMS to support the various use cases the team had identified. It showed that DERMS could be anywhere in a utility architecture. It could, for example, be part of a Distribution Management System (DMS); it could be hosted in the cloud by a third party aggregator; it could be in a substation (as a microgrid controller); or it could be a traditional stand-alone system.
