Distributed Generation

Distributed Generation

We are committed to supporting distributed generation projects within our service area. Whether you are a customer considering distributed generation or you are an experienced contractor, we can help you learn more about distributed generation and guide you through the application process.

What is Distributed Generation?

Distributed Generation, also known as Distributed Energy Resources (DER), involves a generator interconnected to the Electric Distribution System located on either the customer-side or grid-side of the utility meter. The generator produces energy from a variety of sources including but not limited to photovoltaic arrays (solar panels), wind turbines, co-generation units and micro turbines.

UI customers can receive permission to energize and interconnect their DER to the Electric Distribution System. To do so, customers, or their contractors, need to via the interconnection portal using the link found below. The online DER portal is the only acceptable method to submit an interconnection application and acquire a position in UI’s interconnection queue. UI reviews each interconnection application to ensure that the proposed generator can be safely and reliably interconnected to UI’s Electric Distribution System.

DER Interconnection Application Process

An application for a proposed DER interconnection can be submitted via our online portal. In order to do so, you will need to create a secure login ID and password. Once you have submitted an application, you can also view updated project status online through the portal. Click below to apply today!!

We are making enhancements to this site to better serve you. United Illuminating is not currently accepting any new Distributed Energy Resources (DER) applications due to these system upgrades. The DER portal will be back online on Tuesday 1/19. We apologize for the inconvenience. If you need to contact us in the meantime, please email Generator.Connection@uinet.com

Would you like to generate your own electricity?

Whether this is your first project, or you are a seasoned professional, we can help you get connected!

We've included the information needed to set up either a small or large DER project at your home or business location.

Tools to assess options for your residential solar project

Hosting Capacity Eligibility Form

Interconnection Feasibility Map

“How to” guide for the DER Interconnection Application Portal

Guidelines for Interconnection

Interconnection guidelines and applications are based on the type of service, generator technology, and the AC nameplate rating of the proposed generator system.

Basic Interconnection

New — Effective Date:  April 15, 2019

Key changes:

  1. Application Fee--$200
  2. Evidence of insurance is not required
  3. Voltage screening required

Residential Single Phase Certified Inverter-Based Generating Facilities of 20 kW (AC) or Less

Guidelines: Guidelines include IEEE 1547 (the DER interconnection standard).


Certified Inverter Based Generating Facilities, 10kW and Less

Expiration Date:  April 30, 2017


Advanced Interconnection

Fast Track & Study Process Generating Facilities
There are two advanced application process categories:  Fast Track Process and Study Process.

Effective Date:  April 15, 2019

1. Fast Track Process
Interconnecting facilities such as induction, synchronous, certified inverter based generators or other generators producing between 20kW -2MW and successfully passes the screen criteria set forth in Section 4.2.1 of Connecticut State Guidelines qualify for the Fast Track Process.

2. Study Process
Interconnecting facilities such as induction, synchronous, certified inverter based generators or other generators producing between 2MW – 20MW or facilities that fail both Fast Track screen criteria and supplemental modifications will require additional (feasibility, facility, and Impact) studies and acceptance of additional modifications to determine interconnection consistent with safety, reliability, and power quality standards.


Technical Requirements — Technical Requirements include IEEE 1547 (the DER interconnection standard).


Note:  Due to the recent approval of the Guidelines for the Interconnection of Residential Single Phase Certified Inverter-Based Generating Facilities of 20 kW (ac) or Less, Fast Track and Study interconnection applications that are received on or after May 1, 2017 should include only proposed projects that are requested to be interconnected via three phase service and are >20 kW.

For any further questions regarding the DER interconnection process, please send an email to generator.connection@uinet.com.