When to use: Screening-level check of whether a proposed solar, wind, or BESS project at a point of interconnection (POI) is likely to qualify for a fast-track / simplified utility interconnection review versus a full impact study. Mirrors the screening logic used in FERC's Small Generator Interconnection Procedures (SGIP) and many state fast-track tariffs. Educational approximation only — always confirm against the interconnecting utility's actual tariff and a qualified engineer.
This tool applies screening-level logic modeled on FERC's Small Generator Interconnection Procedures (SGIP) fast-track screens to estimate whether a proposed solar, wind, or battery storage project is likely to qualify for a simplified/fast-track utility interconnection review or will likely require a full interconnection impact study. It flags the specific criteria driving any escalation so the reasoning is transparent.
FERC's SGIP framework (and the many state-adopted fast-track/simplified tariffs modeled on it) uses a series of pass/fail technical screens applied at the proposed point of interconnection (POI) before deciding whether a project needs a full interconnection study. Two of the most common screens compare the proposed generator's nameplate capacity to the host circuit's load characteristics: (1) aggregate generation on the line section as a percentage of the circuit's annual peak load — commonly a ~15% threshold — and (2) a reverse power-flow / voltage-rise screen, often triggered when capacity exceeds 100 kW on a shared secondary/service transformer or 20% of the feeder section's minimum daytime load. Falling within these thresholds suggests the circuit can absorb the new generation without a detailed load-flow and protection study.
IEEE 1547-2018 is the governing technical standard for interconnecting distributed energy resources (DER) to the grid, and it defines mandatory voltage/frequency ride-through behavior and anti-islanding protection for inverter-based resources. Many fast-track programs treat IEEE 1547-2018 compliance — with correctly configured ride-through and anti-islanding functions — as a precondition for simplified review, because a compliant inverter is expected to ride through minor grid disturbances rather than nuisance-tripping or, worse, continuing to energize an unintentional island after the utility source disconnects. A non-inverter-based (rotating) generator, or an inverter that is not confirmed 1547-2018 compliant, cannot rely on these built-in protective functions, so utilities typically require a full technical review of protection coordination and anti-islanding scheme regardless of project size.
Distribution feeders are engineered assuming one-directional power flow from the substation to the load. A generator large enough relative to the local minimum daytime load can reverse that flow, causing voltage rise beyond regulator/LTC design assumptions, mis-operation of protective devices calibrated for one-way fault current, and possible islanding hazards for line crews. That's why the minimum daytime load (not just peak load) is screened separately — a project can pass the peak-load screen yet still create daytime reverse flow when the circuit is lightly loaded. Transmission-voltage interconnections (≥69 kV) are excluded from small-generator fast-track processes entirely, since they involve bulk power system reliability studies (NERC/regional transmission organization review) rather than local distribution engineering.
No. This is an educational screening approximation of the general logic used across many FERC SGIP-based and state fast-track tariffs. Every utility publishes its own interconnection tariff/handbook with specific thresholds, application forms, and study fees that can differ from the generic values used here. Always start with the actual interconnecting utility's procedures.
Fast-track (or "simplified"/"expedited") review means the utility can typically approve interconnection based on a shorter technical screening process rather than a full System Impact Study and Facilities Study, saving significant time and study cost. Passing initial fast-track screens does not guarantee approval — a supplemental review can still be triggered if any individual screen fails, and the utility retains discretion to require additional study.
FERC SGIP screens are based on the interconnecting facility's nameplate export capability at the POI, not its energy source. A BESS that can export power to the grid is screened the same way as a solar or wind generator of equivalent capacity, since the technical concerns (reverse power flow, voltage rise, protection coordination, ride-through) are driven by the point of interconnection behavior, not the underlying generation technology.
No. Failing a fast-track screen only means the project is routed to a more detailed study process (supplemental review or full System Impact Study) rather than automatic disqualification. Many projects that fail initial screens are ultimately approved for interconnection, sometimes with additional equipment (e.g., voltage regulation, upgraded protection, or feeder upgrades) identified and funded through the study process.
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