Smart Grid Standards and the Importance of Interoperability

At the dawn of the U.S. railroad in the early 1800s, track gauges ranged from four and a half to seven feet. This lack of standardization complicated inter-regional travel, leading to track gauge standardization by the late 1800s. Today’s electric grid is undergoing a similar transformation. Consumers are rapidly interconnecting smart devices that lack communications standardization, preventing seamless data flow between those devices.

While standards don’t always guarantee interoperability, they are the necessary first step towards achieving and ensuring safe, secure, efficient, and reliable exchanges of meaningful and actionable information between devices.

History of smart grid standards development
Recognizing the convergence of increased renewable energy penetrations with smart and flexible distributed energy resources, the U.S. Department of Energy formed the GridWise Architecture Council (GWAC) in 2004.  Following GWAC’s creation, the National Institute of Standards and Technology (NIST) assumed primary responsibility for coordinating the development of an interoperability framework, including protocols and model standards for smart grid devices and systems. This initial set of 16 interoperability standards, published in 2009, has since grown to more than 200. These standards address smart meters, distributed generation components, communications, and cybersecurity. The growth in the number of standards has coincided with the proliferation of grid-integrated technologies. Conformance to a standard, however, does not necessarily guarantee interoperability.

SEPA and smart grid interoperability
SEPA has a long history of standards work, dating back to the founding of the Smart Grid Interoperability Panel (SGIP) in 2009. SGIP played an important role in coordinating smart grid standards development by contributing technical requirements to standards development organizations to address gaps in standards and the development of the Catalog of Standards. Since SGIP’s merger with SEPA in 2017, smart grid standards coordination has been led by the SEPA Testing & Certification Working Group. This working group develops and facilitates testing and certification frameworks, educates industry on the value of testing, and shares best practices. Their deliverables address two primary areas:

1. Developing interoperability profiles
2. Managing standards-related databases, including the SEPA Catalog of Standards, which houses a collection of standards and practices for the development and deployment of a robust, interoperable, and secure grid and the SEPA Catalog of Test Programs, which houses test programs that are available for smart grid standards.

A previous SEPA blog on interoperability profiles acknowledged that despite new standards, the industry remains constrained by a lack of interoperability at the device/interface level. This lack of interoperability is due to:

1. An abundance of standards that address a single smart grid device.
2. Standards can be intentionally broad to provide rich flexibility and functionality, resulting in too many permitted configuration options.
3. Device-to-device and device-to-software interactions at the system level further complicate communications across domains.

The key to efficient standards utilization
Creating specific configuration profiles that also conform to a standard’s requirements improves interoperability. For customers and manufacturers, these specifications help to ensure the functionality of their grid-connected products. For grid operators and aggregators, they help prevent procurement errors that could compromise reliability, security, and compatibility.

SEPA has partnered with NIST to establish an Interoperability Profiles Task Force (IPTF) as a part of the SEPA Testing and Certification Working Group. The IPTF develops interoperability profiles that specify standards requirements, accepted by industry stakeholders, for smart grid technology applications. Currently, the IPTF is informing the development of an interoperability profile for EV fleet-managed charging use cases. Through information sharing and constructive discussions, the IPTF aims to identify solutions to key issues necessary to assess achievable, beneficial outcomes for utility planners, and EVSE owners and operators. While this Task Force is focused on a profile that will capture functional requirements for interfaces between distribution utilities and managed charging or V1G, it sets a path for future vehicle-to-grid charging  use cases and profiles (V2G).

Guide for smart grid interoperability
While not a standards development organization, SEPA works closely with NIST to maintain a compendium of smart grid standards and practices relevant for the development and deployment of a robust, interoperable, and secure smart grid.  The SEPA Catalog of Standards also contains additional information behind each standard, including domains, subdomains, and components. Each standard goes through a multi-stage vetting process to provide clarity on which standards are, or are not, supported by electric power sector testing and certification programs. This evaluation creates a simplified way for individuals to understand the level of conformity that different standards require, and serves as a necessary step towards greater interoperability. In 2022, SEPA is working with NIST on an enhanced user interface for the Catalog of Standards, and plans to add three existing standards to the guide as a reference to the electric grid community.

Interoperability supports the transition to clean and modern
SEPA envisions a carbon-free energy system by 2050. Interoperability and standards are important components for meeting that vision. As more renewable energy comes online, and other flexible resources are deployed to shift system loads, interoperability is crucial to ensure that those renewable resources are interconnected safely, securely, efficiently, and reliably.