One of the most significant changes to electricity systems around the world has been the emergence of innovative technologies that can support locally owned facilities for electricity generation, control and storage. These technologies, often referred to as Distributed Energy Resources (DERs), are transforming the way communities meet their energy needs.

How DERs Benefit Ontario

DERs are becoming increasingly popular among individuals, businesses and local hydro companies. They:

• Give customers control: DERs reduce reliance on the provincial electricity grid by supplying some (or all) of the energy needed for a home, facility or business, which helps lower electricity bills
• Lower system costs: DERs can be located close to urban centres, which limits (or avoids) the need for new or upgraded transmission lines
• Provide energy security: DERs can be connected to the local or provincial grid, providing back-up power during emergencies

Different Types of Distributed Energy Resources

• Smart Thermostats
• Solar Photovoltaic Systems
• Battery Storage Systems
• Vehicle-to-Grid Charging Stations
• Gas/Wind/Hydro-Electric Turbines
• Co-Generation (combined heat and power)

Micro Generators ≤10kW

Distributed Energy Resources (DER) include solar panels, combined heat and power plants, energy storage facilities, and natural gas-fueled generators. 

Our Engineering Department assesses and approves the connection of all DER connections to our distribution system. 

1. MICRO DER APPLICATION

First, complete and submit the application found below.

      WPI Form C – Micro Generation Connection Application

2. ENGINEERING TECHNICIAN SITE VISIT

Westario Power will review the application and, once it is accepted, a Technician will visit the proposed installation site to gather information to put together the Offer to Connect/Service Layout.

3. MICRO EMBEDDED CONNECTION AGREEMENT AND OFFER TO CONNECT/SERVICE LAYOUT

Westario Power will issue a Connection Agreement and Offer to Connect which outlines the requirements and Westario Power’s costs to connect the generator. If you decide to proceed with the project, you will be required to pay the connection fees detailed in the Offer to Connect/Service Layout.

      Micro Generation Connection Agreement

4. DESIGN & BUILD

Once the micro generation facility has been built according to our requirements, you will need to apply to the Electrical Safety Authority for an electrical inspection.

5. FINAL CONNECTION

Westario Power will schedule a meter change to install the new bi-directional meter. Westario Power will also do the necessary work to ensure billing arrangements are set up based on the project type.

Technical Requirements

Westario Power follows the most recent version of the Hydro One TIR for technical interconnection requirements of DER: Technical Requirements

Small, Mid-Sized and Large Embedded Generators >10kW

Distributed Energy Resources (DER) include solar panels, combined heat and power plants, energy storage facilities, and natural gas-fueled generators. 

Our Engineering Department assesses and approves the connection of all DER connections to our distribution system. 

1. PRELIMINARY CONSULTATION INFORMATION REQUEST

The first step is to complete and submit a Preliminary Consultation Information Request. Westario Power will respond to this request and provide you with the connection details for the proposed project and outline the available capacity. At this time, Westario Power will also provide details for a Connection Impact Assessment through a Preliminary Consultation Report.

    WPI Preliminary Consultation Information Request (PCIR & PCR)

2. CONNECTION IMPACT ASSESSMENT APPLICATION

After the preliminary consultation, complete and submit a Connection Impact Assessment Application. If agreed upon, Westario Power will issue an invoice with the appropriate amount as per the CIA Fee Schedule (to be paid in full prior to performing CIA).

    WPI Connection Impact Assessment Form (CIA)

    WPI CIA Fee Schedule (2025)

3. CONNECTION IMPACT ASSESSMENT

Westario Power and any other affected utility will perform a Connection Impact Assessment for the proposed generator. Westario Power will then issue the report(s) once they are complete. You will be allocated capacity on the grid upon completion of the Connection Impact Assessment by all utilities involved.

Please Note: For generators connecting on a utility shared feeder, that utility maybe required to perform its own Connection Impact Assessment. Details of utilities involved will be provided during the Preliminary Application stage.

4. CONNECTION AGREEMENT/OFFER TO CONNECT

Westario Power provides you with a Connection Agreement for your proposed Generator. Included in the Connection Agreement is a Connection Cost Agreement. This Connection Cost Agreement serves as your Offer to Connect and provides a cost estimation specifying the scope of work to be performed either by you, Westario Power, or upstream utilities, in order to make the generation connection.  

If you decide to proceed with the project, you must sign the Connection Agreement, sign the Connection Cost Agreement, and make the required payments.

      WPI Connection Impact Assessment Study Agreement (Sample)

5. DETAILED DESIGN REVIEW & CONTRUCTION

You will be required to submit a Detailed Design Review to ensure all requirements for the connection have been satisfied. Westario Power will review the Detailed Design and provide feedback and/or approval.

Once the final design is approved you must complete the construction of the generation facility and then apply to the Electrical Safety Authority (ESA) for an electrical inspection.

Concurrently, Westario Power and the upstream utility (if required) will perform the necessary work required for the connection.

      Sample Protection Philosophy for Distributed Energy Resources

6. COMMISSIONING & CONNECTION

You will be required to complete and submit a Commissioning Plan and Commissioning Verification Report.

Depending on the scope of the project, Westario Power may want to witness the commissioning activities.

After the Electrical Safety Authority (ESA) provides us with the electrical inspection “Connection Authorization”, Westario Power will connect the generator to our distribution system to allow for completion of the commissioning activities.

7. FINAL AUTHORIZATION

Once all requirements and commissioning activities have been approved by Westario Power, we will issue an authorization letter that permits the generator to operate within the parameters of their connection agreement.

8. SUPPORT

As DER connections vary in scope and complexity, Westario Power will work closely with you during the entire project from application through commissioning.

Technical Requirements

Westario Power follows the most recent version of the Hydro One TIR for technical interconnection requirements of DER: Technical Requirements

Restricted Feeders 

For more information on circuit capacity to accommodate a generation project, please contact the Engineering Department (wpiengineering@westariopower.com) at Westario Power.