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Smart Grid

Energy Infrastructure Modernization

Interoperability Learning Modules

The Smart Grid Learning Module series includes short (less than 15-minute) videos for state utility commissions on the economics of interoperability, operational considerations for interoperability, and roles and responsibilities of state regulators. Accompanying each module is a list of relevant resources. An Interoperability Glossary is available for reference as well.

NARUC will release new videos throughout 2021. Please contact us if you have a learning module topic recommendation. NARUC thanks the U.S. Department of Commerce National Institute of Standards and Technology (NIST) for its support.

How Interoperability Supports Policy Objectives

Speaker: Dr. Lynne Kiesling, Institute for Regulatory Law & Economics, Carnegie Mellon University | Knowledge Problem, LLC

Dr. Lynne Kiesling provides an overview of several important concepts surrounding interoperability in the electricity system along with the economic benefits of interoperability. Interoperability, by ensuring that components (e.g. DERs) work well together, increases system-wide benefit and helps achieve policy objectives including safety, reliability, resilience, and affordability. Dr. Kiesling also highlighted the difference between resilience and reliability and NARUC’s 2019 report on methods for calculating the value of resilience for DERs.

Additional Reading

Minnesota Updates Interconnection Standards

Speaker: Tricia DeBleeckere, Minnesota Public Utilities Commission (PUC)

Tricia DeBleeckere of the Minnesota PUC staff provides an example of implementing an interoperability standard. DeBleeckere highlights how the PUC updated the state’s interconnection standard from the 2004 to the 2018 updated standard. This update allowed distributed energy resources (DERs) to interconnect to the grid at both the distribution and bulk system and improved coordination between DER operators, distribution system operators, and transmission system operators. The interoperability standard ensured that all DERs interact with the grid in the same way, allowing improved awareness and control.

Additional Reading

Michigan Leverages ZigBee Standards

Speaker: Ryan Laruwe, Michigan Public Service Commission (PSC)

Ryan Laruwe of the Michigan PSC staff provides an example of implementing an interoperability standard. Laruwe highlights his participation with the Smart Grid Interoperability Panel (SGIP) and the application of his knowledge to a Michigan utility’s implementation of ZigBee communication standards for interruptible air conditioning, an update to the previously-used one-way radio communication for the program. The new standard allowed two-way communication and verification of load reduction. The PSC used the ZigBee Alliance to independently certify products’ compliance with the ZigBee standard. The new program was twice as effective as its predecessor and helped leverage new advanced metering infrastructure in the state. Although Michigan did not know of any other states using ZigBee products for A/C demand response, relying on the ZigBee Alliance and its interoperability certification provided the necessary certainty that these new technologies would perform.

Additional Reading

Economic Value of Interoperability and Standards

Speaker: Dr. Lynne Kiesling, Institute for Regulatory Law & Economics, Carnegie Mellon University | Knowledge Problem, LLC

Dr. Lynne Kiesling identifies economic benefits that interoperability brings to the electric grid. Digital innovation, which interoperability helps to unlock, reduces the costs of transactions, interconnection, and of decentralized system components. By implementing an industry-wide consensus through a universal standard, detailed data are more abundant and accessible. Open standards, such as the IEEE 1547 interconnection standard, also reduce costly technological lock-in that comes through proprietary systems (this benefit is also called future-proofing). Interoperability, although it might seem more costly in the short run, increases the long-term value of grid modernization investments and offers lower costs in the long run. Regulators should have some frameworks for assessing the prudence of communications-focused interoperability investments.

Additional Reading

Utilities Working with Suppliers on New Technologies and Interoperability

Speaker: Wanda Reder – Grid-X Partners

Technology adoption usually follows a curve: from innovation to trials and pilots to early adopters to mainstream. Hype for a new technology also often follows a curve: from a peak of inflated expectations to a trough of disillusionment to a final plateau somewhere in between. Commissions and utilities that work with suppliers should align their expectations with a new technology’s position on the adoption curve. Successful innovation relies on collaboration between the utility and suppliers, including feedback, successful demonstrations, stakeholder education, and standards development. Public-private partnerships, such as those that resulted from the American Reinvestment Recovery Act (ARRA), have been important in spurring innovation and adoption of new technologies in the past. While interoperability requirements should be defined initially, usually the specifics become clearer for suppliers as they work with utilities to advance projects. Testing and validation is essential.

Additional Reading

Leveraging Standards to Support Future-Proofing of Grid Investments

Wanda Reder – Grid-X Partners

Wanda Reder provides examples of long-term thinking that increase the benefits and reduce the costs of grid investments. Reder first defines future proofing, promoting approaches that: use standards, emphasize scalable and flexible solutions, leverage open protocols, and anticipate future capability. Reder then provides several examples, included automated metering investments (AMI), EPB Chattanooga’s future-proofed smart grid investments, and California’s planning for a future electrified and decarbonized grid. In general, it is important to define an end state that is clearly linked to macro objectives, to clearly define stages of modernization, to build in flexibility and future-proofing, and to use standards wherever possible.

What is Interoperability?

Speaker: David Wollman, National Institute for Standards and Technology & David Forfia, Gridwise Architecture Council

David Wollman defined interoperability: the ability of two or more systems or components to exchange information and to use the information that has been exchanged. Interoperability, simply, means that devices (and systems and people) work well together. Interoperability allows the exchange of actionable information between two systems or parties across an interface. David Forfia explained the Gridwise Architecture Council’s Interoperability Framework, which outlines three categories of interoperability: organizational, informational, and technical. Different levels of interoperability require a trade-off between short-term effort and long-term cost. Higher levels of interoperability require more effort but are lower cost in the long run.

Additional Reading

Interoperability: Standards, Profiles, and Testing & Certification

Speaker: David Wollman, National Institute for Standards and Technology

Dr. Wollman provides on overview of documentary standards and profiles, which incorporate communication protocols, information models, and hardware to create consensus guidance that allows for common and repeated use. Standards help but do not guarantee interoperability; testing and certification is also needed. Testing and certification of profiles and standards includes both conformance testing (ensuring a product conforms to a standard) and interoperability testing (which can involve physical testing through “plug-fests” to ensure products from different vendors actually interoperate). Of 240 smart grid standards reviewed by NIST, only a small percentage had testing and certification programs existing or planned. Lists of available standards can be found through the Smart Electric Power Alliance’s (SEPA) Catalog of Standards, through the NIST Smart Grid Framework 3.0, and through the websites of standards developing organizations such as IEC or IEEE.

Additional Reading

Example of Standards Development and Adoption

Speaker: David Wollman, National Institute for Standards and Technology

Dr. Wollman describes the interoperability standards development process using the example of Green Button, which allows utility customers to download their own energy usage data. In 2009, NIST identified energy usage information as a key way to empower customers. After finding interest from the White House, NIST worked to resolve coordination issues with multiple stakeholders. Eventually, California utilities began implementing Green Button. In 2015, the Green Button Alliance was launched, and regulators from several states, provinces, and countries have adopted or committed to Green Button Connect (totaling 36.2 million utility meters). The Green Button Alliance maintains testing and certification for the standard to ensure conformance, along with a free validation website and certification training.

Additional Reading

Interoperability Is a Team Sport

Speaker: Steve Widergren – Pacific Northwest National Laboratory

Steve Widergren emphasizes the wide array of participants needed to ensure interoperability. An ecosystem built on interoperability requires: interoperable interfaces for products that are simple to install, update, and manage; testing and certification which develops trust and verifies interoperability before products go to market; and a market ecosystem that acquires interoperable products and supporting services. Alignment by many stakeholders is required. Participation by users, vendors, utilities, trade associations, consultants, standard developing organizations, universities, regulators, and governments is required to ensure interoperability.

Interoperability Strategic Roadmap

Speaker: Steve Widergren – Pacific Northwest National Laboratory

Steve Widergren describes the grid and interoperability using the concepts of “grid architecture” and systems thinking. In grid architecture terms, interoperability drives simplicity of system integration. Architecture requires several features: layered decomposition to ensure coordination follows physical flows, modularity to enforce clear jurisdictions of responsibility, and interface points that allow modules to connect through interoperability agreements. Widergren uses the Energy Services Interface (ESI) as an example to illustrate these points. Currently, there are separate roadmaps for different DER devices (e.g., there different interfaces for electric vehicles compared to solar PV), but these roadmaps should gradually converge over time..

Additional Reading

Ecosystem Interoperability Roadmap Process

Speaker: Steve Widergren – Pacific Northwest National Laboratory

Steve Widergren describes the advancement of interoperability as a process, continually evolving as the electric system evolves. Creating an interoperability roadmap requires strong stakeholder engagement; clear priorities, milestones, and timelines; clear identification of gaps and barriers; and a clear action plan. The entire process is broken down into six phases, including (1) planning, (2) preparation, (3) visioning, (4) roadmap development, (5) roadmap implementations, and (6) adjustment. Interoperability can be measured using a maturity model which looks at 33 interoperability criteria and finds gaps in existing products and standards. Widergren concludes by providing several actions that regulators can take. These include: encouraging utilities and other stakeholders to participate in interoperability ecosystems, ensuring that interoperability requirements are in procurement plans, and ensuring that guidance is focused on performance and not specific technologies.

NARUC CPI Staff experts who support these activities include:

Kerry Worthington