What Is a Hosting Capacity Analysis (HCA)?
Hosting capacity analyses are an analytical tool that can help states and utilities plan for and build a cleaner electric grid that optimizes customer-driven distributed energy resources (DERs), such as rooftop solar, energy storage, or electric vehicle charging stations.
They provide a snapshot in time of the conditions on a utility’s distribution grid that reflect its ability to “host” additional DERs at specific locations on the grid—without the need for costly grid upgrades or lengthy interconnection studies. They are often displayed in the form of maps with supporting datasets.
IREC has been actively involved in regulatory proceedings and research projects related to HCA development around the country, including in California, Colorado, New York, Massachusetts, Nevada, and Minnesota. These experiences have yielded a number of lessons about the factors necessary to produce a useful HCA, which IREC has shared in reports, articles, and other formats.
This page provides an overview of hosting capacity analysis and IREC’s related resources for regulators, utilities, and other clean energy stakeholders. Read on to explore our related reports, blog posts, and webinars. We also share links to other helpful external resources like the hosting capacity maps of utilities around the country.
Why Are Hosting Capacity Analyses Important?
HCAs provide greater transparency into the grid. They can help reveal the operational limits of the grid, which impact the ability of new DERs to interconnect quickly or affordably. They can also identify areas where DERs may be able to provide beneficial services by addressing existing grid constraints and inform more strategic grid investments over the long term.
Since they first began being developed around 2015, hosting capacity maps have been rapidly increasing in popularity. As the growth of DERs has accelerated, more and more states are requiring or actively considering the development of HCAs to better support the integration of these resources.
However, not all HCAs are created equal. A number of decisions in the process of their development will shape how useful and reliable they are for different purposes. IREC has detailed these considerations in the report Data Validation for Hosting Capacity Analyses, co-authored with the National Renewable Energy Laboratory. Related considerations are also discussedin our blog post Validation Is Critical to Making Hosting Capacity Analysis a Clean Energy Game-Changerand touched upon in our report Key Decisions for Hosting Capacity Analyses.
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.
Sky Stanfield, attorney for IREC and Partner at Shute, Mihaly & Weinberger
Data Validation for Hosting Capacity Analyses
To improve HCA data and avoid the common challenges encountered in previous analyses, NREL and IREC compiled best practices for HCA data validation, which can be beneficial for:
- Utilities, to develop or refine their HCA data validation procedures
- Regulators, to inform their oversight of utilities’ HCA data validation practices
- Other stakeholders, to evaluate the effectiveness of utility efforts.
Learn more about HCA validation on our related webpage, or by reading the report Data Validation for Hosting Capacity Analyses.
HCA Resources
Articles and Blog Posts Exploring Key Hosting Capacity Considerations
- Validation Is Critical to Making Hosting Capacity Analysis a Clean Energy Game-Changer (June 13, 2020)
The usefulness of an HCA is highly contingent on having confidence that its results accurately reflect grid conditions at the site. This article explores important lessons for how regulators can ensure the quality and usefulness of hosting capacity maps by building in requirements for utilities to validate the accuracy of both the inputs and outputs.
- What Grid Transparency Looks Like (August 20, 2019)
California was one of the first states to require hosting capacity analyses (which it refers to as integration capacity analyses or ICAs). This article provides an overview of California’s ICA and why it matters. It highlights the features, capabilities, and merits of the different utilities’ ICA results and maps, and outstanding issues to address. Next steps are then previewed, including how these tools will be applied to streamline the process of interconnecting DERs to the grid and to inform distribution planning.
- The Evolution of Hosting Capacity Analysis as a Grid Modernization Tool (October 4, 2018)
In this in-depth article, we address some of the recent developments on HCA as they continue to evolve and as healthy debates about the tool and its uses play out in more states. We set out to ask—and explore answers to—the following key questions surrounding HCA:
-Can hosting capacity analysis be used to streamline the interconnection process for DERs?
-How should the accuracy of hosting capacity results be evaluated?
-How much methodological transparency is needed?”
- Key Lessons from the California Integrated Capacity Analysis (October 16, 2018)
This article introduces hosting capacity analysis and details related efforts in California (where HCAs are called integration capacity analyses or ICAs). We explore why ICAs matter, summarize key findings from the California Working Group effort on this issue, and highlight important insights that are transferable to other states seeking to enable a more modern grid.
Reports, Webinars, and Other Longform Resources on Hosting Capacity Analysis
- Report: Data Validation for Hosting Capacity Analyses (April 14, 2022)
IREC partnered with the National Renewable Energy Lab (NREL) to identify best practices for producing trusted, validated HCA results reflecting real-world grid conditions. This report identifies best practices for utilities to develop or refine their HCA data validation procedures, aids regulators in their oversight of utilities’ HCA data validation practices, and helps other stakeholders evaluate the effectiveness of HCA data.
- Webinar: Key Decisions for Hosting Capacity Analyses (October 6, 2021)
IREC hosted a webinar on October 6, 2021 covering the Key Decisions for Hosting Capacity Analyses paper. Speakers Yochi Zakai, Sky Stanfield, and Radina Valova discussed key decisions in the development of an HCA, the implications of these decisions on the final HCA and how useful it is to support the deployment of DERs, including both generation (e.g., solar and storage) and load (e.g., transportation and building electrification), and real-world examples from states that have already navigated the HCA development process.
- Report: Key Decisions for Hosting Capacity Analyses(September 16, 2021)
This paper is designed to help readers understand the variety of issues and decisions that need to be considered as a public-facing HCA is developed—in order to ensure it is useful in informing the integration of more DERs on the grid. IREC has been actively involved in regulatory proceedings and research projects related to HCA development around the country, including in California, Colorado, New York, Massachusetts, Nevada, and Minnesota. These experiences yielded a number of lessons about the factors necessary to produce a useful analysis which other states can leverage to maximize the success of their HCA efforts.
- Report: Optimizing the Grid: Regulator’s Guide to Hosting Capacity Analyses (December 1, 2017)
Utility regulators play a key role in ensuring HCAs are deployed strategically, prudently, and for the benefit of all energy customers. Optimizing the Grid: A Regulator’s Guide to Hosting Capacity Analyses for Distributed Energy Resources will assist state regulators in guiding and overseeing utilities as they conduct hosting capacity analyses on their distribution circuits, as part of a broader grid modernization or distribution planning efforts and/or in support of their state’s near- and long-term energy policy goals.
Based on lessons from the handful of states and utilities that have begun to prepare HCAs, this guide focuses on the process that will help regulators realize HCAs’ full promise in their respective states. The experiences and key takeaways from the states and utilities undertaking these analyses, including California, New York, Minnesota, Hawaii, and Pepco Holdings, Inc., provide important insights for other states and utilities to take into consideration as they pursue similar efforts.
- Webinar: New Tools for Building the Modern Grid (December 17, 2017)
IREC hosted a webinar on January 10, 2018 about hosting capacity analysis and its report Optimizing the Grid: A Regulator’s Guide to Hosting Capacity Analyses for Distributed Energy Resources. Report authors Sky Stanfield, Stephanie Safdi, and Sara Baldwin provided an overview and insights on the findings and recommendations from the guide, including lessons learned from states already engaged in HCA efforts.
Report: Integrated Distribution Planning Concept Paper (May 19, 2013)
In this 2013 concept paper, IREC and Sandia National Laboratories propose an Integrated Distribution Planning (IDP) approach to proactive planning for distributed generation (DG) growth. Because hosting capacity analyses can be used to inform IDP, this paper may be helpful for readers interested in learning more about that process.
Articles and Press Releases About Specific State Developments Related to HCAs
- CPUC Ruling Improves a Key Grid Transparency Tool for Siting Renewables, Energy Storage (February 2, 2021)
- California Adopts First Interconnection Rules to Utilize Hosting Capacity Results (September 24, 2020)
- Minnesota PUC Requires Hosting Capacity Analysis Improvements (August 20, 2020)
- Nevada’s latest step for consumer-driven clean energy: distribution resource planning reforms (September 9, 2019)
- MN Utility Commission Pushes Xcel Energy to Improve Grid Transparency Tools (August 21, 2019)
- Nevada Closer to Ensuring Electric Grid Better Integrates Distributed Energy Resources (September 26, 2018)
- States Continue to Lead the Way for Clean Energy: Maryland and Minnesota Make Strides for Customer-Driven Distributed Energy Resources (September 7, 2018)
