DOE Distributed Energy Resource Interconnection Roadmap

This goal shows how execution and analysis of interconnection studies could be enhanced by more transparent and accessible data sharing and strategic use of automation. Utilities providing access to grid data must balance the value created with the strains on workforce and computing requirements and with the confidentiality and security of the data. Regulators have a key role in providing guidance to utilities that are beginning to develop methods to access grid and interconnection queue data, as well as those expanding and enhancing data access. 

Solutions

• Establish guidelines for collecting and sharing grid data that consider trade-offs between value created, effort required, and data security and accessibility concerns.
• Expand and standardize reporting of interconnection data, including project attributes and interconnection cost estimates.
• Standardize and clarify the technical data that developers of large DER systems must provide on interconnection applications to facilitate interconnection studies.
• Establish and maintain frequently updated hosting capacity analysis tools that model the impact of multiple types of DER technologies on the grid.
• Broaden the use cases for hosting capacity analysis.

This goal focuses on solutions to streamline the interconnection process—mitigating bottlenecks that result from misalignment between queues designed for a small number of interconnection requests and rapid growth of DERs requesting connection to the grid. This section covers solutions to improve queue management practices, inclusive and fair processes, and workforce development.

Queue Management

Several incremental queue management solutions may help reduce DER queue volumes and interconnection delays in the near term while enabling utilities to handle larger and variable DER queue volumes in the longer term.

Solutions

• Provide pre-application educational materials and self-service options for smaller DER projects.
• Establish and require that large DER interconnection applicants meet clear criteria for commercial readiness and queue dwell-time.
• Implement and enforce appropriate DER interconnection study timelines and consider penalties for delays in completing studies.
• Continue automating parts of DER interconnection application processing.
• Implement automation, where possible, to streamline completion of interconnection studies.
• Enable flexible interconnection so DERs can be used to defer grid upgrades and avoid delays in exchange for curtailing generation.
• Use a group study process to address existing queue backlogs or avoid anticipated queue backlogs.
• Develop and standardize an interconnection process for DERs connected to new building construction projects.

Inclusive and Fair Processes

While the goals of the roadmap aim to promote a fair interconnection process for all, not all of the interconnection community starts with the same tools and resources. Achieving equitable outcomes in DER interconnection processes requires intentionally designing systems, technologies, procedures, and policies for the entire interconnection community. Interconnection customers from socioeconomically disadvantaged or Tribal communities may lack the financing and resources needed to navigate interconnection processes. These processes could be made more inclusive and fairer by acknowledging and addressing these barriers to expanding equitable DER interconnection access. In addition to the two solutions below, which exclusively focus on inclusivity and fairness in interconnection, many other solutions in the roadmap aim, in part, to resolve current issues of equity within the interconnection process.

Solutions

• Advance equitable interconnection through distribution system planning.
• Help under-resourced groups navigate the interconnection process through independent dispute resolution, engineering, administrative, and legal services.

Workforce Development

Interconnection requires technical expertise from many professions in the electric sector. Targeted efforts to increase training opportunities and improve compensation for current staff will improve workforce capabilities, increase retention, and enhance diverse and equitable representation within the interconnection workforce. Also important are broader outreach and recruitment efforts intended to raise awareness of interconnection jobs as a key component of the clean energy workforce and ensure that interconnection skills and knowledge are included in educational curricula.

Solutions

• Assess the growth of the interconnection workforce required to support anticipated growth in DER interconnection requests.
• Upskill the DER interconnection workforce through continuing education.
• Enhance retention and targeted recruitment for DER interconnection-related jobs.
• Grow the interconnection workforce via outreach, curriculum development, and partnerships in postsecondary education.

This goal seeks to improve DER interconnection outcomes that meet market and policy objectives fairly at lower costs to ratepayers. This section covers solutions to improve cost allocation, coordination between interconnection and grid planning, and interconnection studies.

Cost Allocation

Interconnection costs can be allocated in various ways to improve economic efficiency and equity. When considering cost allocation with respect to interconnecting DERs, it is important to think beyond the traditional “cost-causer-pays” model.

Solutions

• Reform the existing “cost-causer-pays” model, such that the cost of interconnection-triggered upgrades is equitably distributed among those that benefit from the upgraded feeder circuit.
• Build a reserve fund by collecting fees from all interconnecting DER customers and spend the fund on upgrades triggered by subsequent interconnections.
• Use a group study process that reduces per-project interconnection upgrade costs by allocating costs among multiple projects based on their contribution to the triggered upgrade.
• Proactively upgrade feeder circuits to accommodate forecasted DER growth and recover costs from future DER developers who share the upgraded feeder circuits.

Coordination Between Interconnection and Grid Planning

Cost inefficiencies in interconnection arise in part because some system-level upgrades are typically triggered through the interconnection process, meaning they often occur in a piecemeal fashion. This type of piecemeal approach can risk imposing costs on interconnection customers or ratepayers depending on how regulators balance risks. Closer alignment of data inputs, assumptions, and process timelines between interconnection and long-term grid planning can help ensure more efficient and forward-looking identification and deployment of potential upgrades.

Solutions

• Coordinate interconnection for DER projects across the distribution, sub-transmission, and transmission systems.
• Improve coordination and data sharing between the DER interconnection process and the system planning process to promote synergy between the two.

Interconnection Studies

Interconnection study methods must evolve to promote safe and reliable DER interconnection while reducing the need for costly and time-intensive system upgrades.

Solutions

• Distinguish between a generator’s nameplate capacity and export capacity in interconnection studies to accurately reflect project impacts.
• Account for potential grid benefits and costs due to DERs in interconnection studies.
• Allow flexible interconnection as a way to mitigate system upgrade costs assigned by interconnection studies.

This goal centers on maintaining a reliable, resilient, and secure grid by addressing the performance of inverter-based DERs during normal operation and outage conditions. This section describes solutions to improve interconnection models and tools. It also identifies solutions to encourage widespread adoption of existing standards and support development of new standards for emerging technologies and issues, including growing cybersecurity issues.

Interconnection Models and Tools

Improvements to interconnection models and tools are needed to support deploying DERs while maintaining grid reliability.

Solutions

• Proactively develop and implement new DER-ready system protection schemes.
• Develop alternatives to address unintentional islanding and provide research-based methods to evaluate their cost-effectiveness.
• Optimize development and use of electromagnetic transient (EMT) models for evaluating the dynamic performance of DERs.
• Improve models for analyzing the seam between the transmission and distribution/sub-transmission systems.
• Collect data from DERs to validate models that ensure aggregate compliance with bulk power system (BPS) reliability standards and to perform large-scale reliability assessments.

Interconnection Standards

To ensure reliable operation of newly interconnected DERs, comprehensive interconnection standards are necessary. 

Solutions

• Accelerate adoption of the Institute of Electrical and Electronics Engineers (IEEE) 1547 interconnection standard via collaboration among regulators, utilities, and researchers.
• Develop standards to mitigate the potential impact of inadvertent export.
• Use guidance from IEEE Std 1547.3 to address cybersecurity concerns during the interconnection process.
• Develop a cybersecurity risk management plan for interconnecting projects.
• Develop and adopt standards that address performance from emerging technologies such as grid-forming inverters and vehicle-to-grid systems.
• Develop evidence-based interconnection best practices that promote safety and reliability while allowing for local or regional differences.