NIPSCO interconnection application

Documents NIPSCO asks for

• Interconnection application formRider 679 Application for Interconnection (Level 1 <=25 kW, or Level 2/3 >25 kW); AC nameplate output, inverter model, operating modes, export kW Gridpol prepares this.
• Other utility-specific documentSigned New Applicant DG Customer Letter
• Single-line diagram (one-line)Single-line diagram from facility to point of interconnection incl. inverters, storage, Utility AC Generator Disconnect, panels, breakers Gridpol prepares this.
• Other utility-specific document (when applicable)Control drawings for relays and breakers
• Site plan / site layoutLocation of generators, inverters, storage, disconnect, service panels and utility meter Gridpol prepares this.
• Inverter spec sheetManufacturer, model, AC full-load nameplate rating, operating manual or link
• Other utility-specific document (when applicable)Protective relay / inverter operating-mode settings applicable to interconnection
• UL 1741 / IEEE 1547 certificationDocumentation that an NRTL has listed the equipment (IEEE 1547-2018 / UL 1741)
• Interconnection agreementLevel 1 interconnection agreement executed and returned at least 10 business days before operation
• Proof of insurance (when applicable)Proof of reasonable insurance upon NIPSCO request (170 IAC 4-4.3-10); larger-facility agreement specifies CGL/umbrella limits

How the NIPSCO process runs

1. Email application, attachments and signed New Applicant DG Customer Letter to cnb@nisource.com (or mail to NIPSCO New Business, 801 E. 86th Ave., Merrillville, IN 46410); Level 2/3 fee with application.
2. NIPSCO completeness notice (10 BD) and technical review; possible additional study.
3. Approval notice; NIPSCO sends interconnection agreement and states whether inspection is required.
4. Customer signs agreements and returns them at least 10 business days before operation, stating anticipated start date; construction may begin once agreements are complete.
5. Install; local electrical code approval; NIPSCO inspection if required.
6. NIPSCO approves interconnection and installs new meter per NIPSCO standards; do not operate before.

Fees

Utility fees are paid by the installer or customer; they are not part of the Gridpol plan.

Size levels and limits

EDG: nameplate <1 MW or average annual consumption. >500 kW requires direct transfer trip (costs from $125,000). Software output limiting not accepted to reduce applied nameplate.

Storage, EV and stamps

Common issues the utility lists

• Incomplete application: NIPSCO returns a list of missing information (170 IAC 4-4.3-6(i))
• Level 1 screens failed (circuit penetration 5%/10%, fault current, shared secondary 20 kVA, 240 V imbalance, network/transmission PCC) -> denied; may resubmit under Level 2/3

Gridpol’s pre-submission check covers these before we file.

Sources

• NIPSCO Excess Distributed Generation Tariff: https://www.nipsco.com/services/renewable-energy-programs/excess-distributed-generation-tariff (retrieved 2026-11-13)
• NIPSCO Rider 679 Application for Interconnection Level 1/2/3 (eff. 02/27/2026): https://www.nipsco.com/docs/librariesprovider11/services/renewable-energy-programs/renewable-energy-program/applications/level-1/net-metering-interconnection-application-level-1.pdf?sfvrsn=2eaa6f51_8 (retrieved 2026-11-13)
• NIPSCO Rider 679 Interconnection Standards (fees, agreements): https://www.nipsco.com/docs/librariesprovider11/rates-and-tariffs/electric-rates/2023-to-current/nipsco-electric-service-tariff-rider-679.pdf (retrieved 2026-11-13)
• IURC Final Rulemaking RM 24-01 amending 170 IAC 4-4.3 (Level 1 to 25 kW, timelines): https://www.in.gov/iurc/files/ord_RM24-01_093025.pdf (retrieved 2026-11-13)