Why Improve Energy Storage Interconnection?
Energy storage has a unique and pivotal role to play in the transition to a low-carbon economy because it can help the electric grid accommodate more renewable energy. However, a number of barriers currently impede the process of connecting energy storage systems to the distribution grid. A new suite of actionable recommendations for regulators and utilities, from a team of leading industry players, aims to change that.
The Toolkit and Guidance for the Interconnection of Energy Storage and Solar-Plus-Storage, the “BATRIES Toolkit” which this website houses, provides vetted solutions to eight regulatory and technical barriers to the interconnection of energy storage solar-plus-storage systems to the distribution grid. These recommendations are based on over a year of research and analysis by utility and industry experts. The Toolkit also includes model language that utility regulators can use to update state interconnection rules to reduce the costs and time to safely interconnect energy storage and solar-plus-storage systems. The solutions are nationally applicable and can be applied in diverse states and markets across the U.S.
The Toolkit is the result of a multi-year project called “BATRIES” (Building a Technically Reliable Interconnection Evolution for Storage), supported by a cooperative agreement with the U.S. Department of Energy Solar Energy Technologies Office.
Adoption of these solutions can have a significant impact on how many distributed energy resources (DERs), like solar PV systems, can be added to the grid. Research for the Toolkit found that when energy storage is used to control energy export from DERs, the grid can host more DERs—in some cases doubling available DER capacity on a circuit!
Solutions to 8 Storage Interconnection Barriers
Energy Storage in Interconnection Rules
Lack of inclusion of storage in interconnection rules, and lack of clarity as to whether and how existing interconnection rules apply to storage systems (addressed in Chapter II)
Control of Limited- and Non-Export DER Systems
Lack of inclusion of acceptable methods that can be used for controlling the export of energy from limited-and non-export distributed energy resource (DER) systems in interconnection rules (addressed in Chapter III)
How to Evaluate Limited- and Non-Export DER Systems
Evaluation of non- and limited-export systems based on unrealistic operating assumptions that lead to overestimated grid impacts (addressed in Chapter IV)
Impacts of “Inadvertent Export”
Lack of clarity regarding the impacts of inadvertent export (power that is unintentionally exported from a DER when load drops off suddenly) and lack of a uniform specification for export control equipment response times (addressed in Chapter V)
Distribution Grid Transparency
Lack of information about the distribution grid and its constraints that can inform where and how to interconnect storage (addressed in Chapter VI)
Design Changes in Interconnection Process
Lack of ability to make system design changes to address grid impacts and avoid upgrades during the interconnection review process (addressed in Chapter VII)
Aligning Interconnection Rules with Technical Standards
States that have not incorporated updated standards into their interconnection procedures and technical requirements (addressed in Chapter VIII)
How to Evaluate “Operating Schedules”
Lack of defined rules and processes for the evaluation of operating schedules, or schedules of when a DER will export energy to the grid (addressed in Chapter IX)
The project team is led by the Interstate Renewable Energy Council (IREC) and includes the Electric Power Research Institute (EPRI), the Solar Energy Industries Association (SEIA), the California Solar & Storage Association (CALSSA), utilities New Hampshire Electric Cooperative Inc. (NHEC) and PacifiCorp, and law firm Shute, Mihaly & Weinberger, LLP (SMW).