Tools to Build the Modern Grid

18 Dec 2017

The 'grid of the future' is no longer a distant goal; it is upon us today with the adoption of innovative tools, technologies and resources that facilitate the transition to a cleaner, consumer-driven electric grid.

A new in-depth guide released by the Interstate Renewable Energy Council (IREC) will help states manage the grid redesign with new analytical tools and the benefit of lessons learned from states leading the way.

More Americans are choosing increasingly economical and available distributed energy resources (DERs) - such as rooftop or community solar, energy storage and electric vehicles - and these DERs create new opportunities and challenges as they are integrated into the traditional electric system.

Optimizing the Grid: A Regulator's Guide to Hosting Capacity Analyses for Distributed Energy Resources  helps guide state regulators as they oversee utilities developing hosting capacity analyses to integrate DERs on their distribution systems. Hosting capacity analyses are a new analytical tool - as part of broader grid modernization or distribution planning efforts - thatcan help states and utilities plan for and build a modern grid that allows for the benefits of DERs to be fully realized by more individuals, businesses and institutions.

"With consumers motivated by economic, environmental and community resilience objectives, distributed energy resources are no longer small asterisks at the edge of the electricity grid (or the economy)," says IREC Regulatory Program Director Sara Baldwin Auck. "Rather than simply 'tolerating' DERs, there is an opportunity to utilize this new tool - hosting capacity analysis - to proactively integrate them into grid planning, operations and long-term investment decisions." 

The term "hosting capacity" refers to the amount of distributed energy resources that can be accommodated on the distribution system at a given time and at a given location, under existing grid conditions and operations, without adversely impacting grid safety or reliability and without requiring significant infrastructure upgrades.

"Hosting capacity analyses allow utilities, regulators and electricity customers to make more efficient and cost-effective choices about where, when and how to deploy distributed energy resources on the grid," explains lead author of the new guide, Sky Stanfield, a regulatory attorney representing IREC. "If adopted with intention, this analytical tool may also function as a bridge to span information gaps between developers, customers and utilities, enabling more productive grid interactions and more economical grid solutions.”  

Process is Key

The process underpinning a hosting capacity analysis is key to ensuring that the tool is deployed to support relevant state policy goals, has clearly defined use cases, and that it sufficiently reflects the input from all involved stakeholders. The desired result is enhanced benefits for all ratepayers. IREC's Optimizing the Grid outlines several key considerations when evaluating and selecting methodologies, and also provides detail on identification of key process steps.

Perspective

Historically, utilities have maintained sole control and oversight over the distribution system. They have prioritized large centralized investments and traditional grid infrastructure to meet expected increases in consumer demand for electricity. Because distributed energy resources fundamentally change consumer electricity demand, they impact the assumptions for growth, the investment needs, grid planning and operations. These energy resources also change how consumers and third-party service providers engage both with technologies and their utilities. 

"Instead of reacting to consumer adoption of distributed energy resources, a tool such as hosting capacity analysis allows for improved transparency and insight into the electric distribution system, a key step toward realizing a modern, clean and resilient grid," says report co-author, Stephanie Safdi. "Based on lessons from the handful of states and utilities that have begun to prepare hosting capacity analyses, this new guide focuses on the process that will help other regulators as they oversee their own state's development and implementation."

There are two principal applications, or use cases, for a hosting capacity analysis (discussed in detail in the new guide): 1) assist with and support the streamlined interconnection of DERs on the distribution grid; and, 2) enable more robust distribution system planning that ensures transparent information is available to all involved parties and that DERs are incorporated and reflected in future grid plans and investments. A third, complementary function could be to inform pricing mechanisms for DERs, to assess their benefits based on their physical location on the grid and performance characteristics.

In addition, the guide for utility regulators offers detailed insight on the different methodologies that can be used for hosting capacity analyses. This is critically important, as the methodology can result in different hosting capacity values (due to different technical assumptions built into the models), and can significantly impact whether the results are sufficiently reliable and informative for grid-related planning and decision making. The guide also highlights factors relevant to evaluate the performance of the hosting capacity analysis, as they relate to identified goals, including how to validate results to improve accuracy and functionality over time.

"Still an emerging grid modernization tool, the benefits and drawbacks of different hosting capacity methodologies are just now being revealed, and likely will become even more apparent with time," says Stanfield. "Regulators will find value in taking initial steps now to gain familiarity and ensure that the tool being developed is capable of meeting identified objectives."

IREC | http://www.irecusa.org