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Municipal utilityGroton Dept of Utilities interconnection application
Groton Dept of Utilities is a municipal utility serving 12,596 residential customers in Connecticut (EIA-861, 2025). Gridpol files Groton Dept of Utilities interconnection applications for licensed installers – solar, storage and EV chargers – with single-line diagram and site plan, unlimited for $500 a month.
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Connecticut’s commission rule (PURA-approved EDC Guidelines: Docket 17-12-03 RE06 'Guidelines for Generator Interconnection - Fast Track and Study Processes' (Eversource/UI, 2023-12-20) and Docket 03-01-15 RE04 'Guidelines for the Interconnection of Residential Single Phase Certified Inverter-Based Generating Facilities' (<=25/50 kW)) does not bind municipal utilitys; Groton Dept of Utilities sets its own interconnection policy. We confirm its form on the first project. Municipal electric utilities (CMEEC members, e.g. Norwich, Groton, Wallingford) are not under the PURA EDC guidelines and set their own interconnection/net metering policies.
Groton Dept of Utilities at a glance
Groton Dept of Utilities
TypeMunicipal utility
EIA utility ID7716
Residential customers12,596 (EIA-861, 2025)
Net-metered residential customers822 (EIA-861, 2025)
Service territory1 county in Connecticut
Documents Groton Dept of Utilities asks for
- Interconnection application formFilled in by us from your project data in the utility’s portal or on its form. Gridpol prepares this.
- Single-line diagram (one-line)Drawn by us from your equipment data: modules, strings, inverter, battery, disconnects, point of interconnection, meter. Gridpol prepares this.
- Site plan / site layoutDrawn by us from your roof sketch or photos: array, inverter, battery, disconnect, meter and main panel locations. Gridpol prepares this.
- PV module spec sheetManufacturer data sheet of the modules.
- Inverter spec sheetManufacturer data sheet (string inverter, microinverter or hybrid inverter).
- Customer signatureThe account holder signs the application or authorization. We send the signature link.
- Recent electric billName, service address, account and meter number must match the application.
- Final inspection sign-offApproved electrical inspection from the authority having jurisdiction after installation.
Typical documents for US utilities – not yet verified for Groton Dept of Utilities. We confirm Groton Dept of Utilities’s exact list on the first project.
Connecticut interconnection rule
Connecticut Public Utilities Regulatory Authority (PURA)
Interconnection rulePURA-approved EDC Guidelines: Docket 17-12-03 RE06 'Guidelines for Generator Interconnection - Fast Track and Study Processes' (Eversource/UI, 2023-12-20) and Docket 03-01-15 RE04 'Guidelines for the Interconnection of Residential Single Phase Certified Inverter-Based Generating Facilities' (<=25/50 kW) – Guidelines for Generator Interconnection · source
Applies toThe two electric distribution companies: Eversource (CL&P) and United Illuminating; not municipal utilities (CMEEC members)
Application formJoint EDC interconnection request submitted through each EDC's online portal (Eversource PowerClerk); separate simplified residential inverter guideline application
TimelinesFast Track/Study guideline: receipt confirmation 3 business days, completeness notice 10 business days, applicant 15 business days to cure; generator signs agreement within 30 business days; EDC witness test within 10 business days of request.
Fees$200 inverter-based <=25 kW; $500 Fast Track; $1,000 Study + actual study costs (Table 1 of guideline; Eversource CT page).
InsuranceGeneral liability per guideline Table 2: <100 kW $300,000; >100 kW-1 MW $1,000,000; >1-5 MW $2,000,000; >5 MW $5,000,000; Eversource page lists N/A for inverter-based 0-25 kW but asks proof of insurance in residential application.
External disconnectEversource CT: isolation device (AC disconnect) must be visible and within 10 feet of main utility panel/meter; variance needs written approval.
Export compensationNet billing – CGS 16-244z (Residential and Non-Residential Renewable Energy Solutions programs); legacy net metering CGS 16-243h
Traditional net metering closed to new residential customers end of 2021; RRES offers netting or buy-all tariff at fixed rates for the program term; NRES for non-residential. Program-year details not verified here.
Municipal electric utilities (CMEEC members, e.g. Norwich, Groton, Wallingford) are not under the PURA EDC guidelines and set their own interconnection/net metering policies.
- Guidelines for Generator Interconnection Fast Track and Study Processes, Docket 17-12-03 RE06: https://www.eversource.com/Content/docs/default-source/ct---pdfs/guidelines-generator-inter-fast-track.pdf (retrieved 2026-11-13)
- Eversource CT - Application to Connect: https://www.eversource.com/residential/about/doing-business-with-us/interconnections/connecticut/connecticut-application-to-connect (retrieved 2026-11-13)
- PURA Distributed Generation Policy Working Group: https://portal.ct.gov/PURA/Electric/Interconnection-Policy-Working-Group (retrieved 2026-11-13)
Other utilities in Connecticut
$500 / month
Unlimited interconnection applications. 12-month agreement, signed online. The agreement starts the day you sign; first invoice right away, then monthly.
- Unlimited interconnection applications
- Single-line diagram and site plan for every application
- Pre-submission check against the utility’s requirements
- Homeowner e-signature link for the authorization
- Filing in your utility portal accounts or by the utility’s method
- Utility questions, corrections and resubmissions
- Follow-up through approval, inspection and PTO
- Customer list, exports, API and webhooks
Applications are typically submitted within 2 business days after complete documents. Utility review times are set by each utility.