Interconnection Study

An interconnection study is the set of engineering analyses a grid operator runs to decide whether and how a new generator, storage project or large load can connect to its network, what upgrades are needed and who pays for them. The results define the project's connection design, cost allocation and timeline, and they underpin the interconnection agreement it eventually signs.

In most North American processes, studies proceed in stages. A feasibility or screening study gives a first view of constraints. A system impact study runs power flow, short circuit, stability and sometimes electromagnetic transient analysis to identify overloads, voltage violations and stability risks. A facilities study then designs and estimates the cost of the interconnection facilities and network upgrades. Many operators now study projects in clusters, sharing upgrade costs among projects that enter the queue together.

Outside North America the structure differs. European and Asian TSOs and DSOs often issue a connection offer based on their own studies, and some require developers to commission studies from approved consultants. Requirements for validated dynamic models of inverter-based plants have become stricter everywhere as grids rely more on power electronics.

Study outcomes are a major source of project risk. Large upgrade cost assignments or long timelines cause many projects to withdraw, which then triggers restudies for those that remain in the cluster. Developers increasingly run their own pre-application screening, testing hosting capacity, nearby constraints and competing queue positions before committing deposits, and software vendors are automating parts of the study process to shorten timelines.