Staying Connected: Bulk Electricity System Planning in Northeastern Ontario – July 27, 2021




The IESO is in the midst of electricity planning activities in Northern Ontario to address system constraints that could affect the ability to supply electricity demand growth in northern communities and industry. Driven by potential significant growth primarily in large industrial customers, the Northeast bulk plan will examine upstream bulk electric system impacts to the Northeast area and develop an approach to address identified needs.

A public webinar was held on July 27 at 10:00 a.m. to provide an overview of the scope of the Northeast bulk system planning process and how it fits with the overall context of electricity planning across Northern Ontario.

We will engage with stakeholders and communities in two phases throughout the development of a Northeast bulk plan. As part of the first phase, this webinar provided an overview of the bulk planning process and the scope of the study underway including the assumptions underlying the scenarios being studied. These scenarious form the basis for identifying and characterizing future electricity needs. We appreciated the opportunity to provide you with this background information and answer your questions.

As part of phase two, we will present the preliminary results of the study and seek feedback from communities and stakeholders on any recommendations that emerge as a result. This feedback will be important in finalizing the Northeast bulk system plan.

Thank you for joining this Staying Connected webinar to learn more about Bulk Electricity System Planning in Northeastern Ontario.

Please comment below if you have any further questions.

The webinar was livestreamed, and the recording is now available.

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Bulk system planning looks at the ability to transfer power between regions on the provincial high-voltage transmission networks, managing what’s ahead in terms of provincial demand and supply and investigating big changes that can impact the system.

This is distinct from regional electricity planning which focusses on ensuring the system is able to deliver enough power into regions and load centres. IESO coordinates these two levels of planning.


Map of the Northwest Ontario and Northeast Ontario electricity transmission zones and anticipated projects


Meet the Speakers

Rouselle Gratela

Advisor Stakeholder Engagement, Community Engagement & Customer Outreach

Ahmed Maria

Director Transmission Integration


Kun Xiong

Sr Transmission Planning Engineer


Christopher Reali

Engineering Manager Transmission Planning, Interfaces & Interties


Beverly Nollert

Manager Transmission Planning


Have further questions to ask. Write in the comments below.

You can use the form below to submit your questions. Please note that submitted questions will be displayed publicly.

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Sulteck's avatar
Jul 22, 2021 - 16:55

This webinar is about Northeastern Ontario. Why are you displaying a Sunrise picture over Sault Ste. Marie, Michigan?

IESO Community Engagement's avatar

IESO Community Engagement
Jul 23, 2021 - 13:29

Great catch! Thanks for your comment – we have corrected it. IESO Community Engagement

Daryle's avatar

Jul 27, 2021 - 10:06

Where can I find the slides on the IESO website - looking for them but I do not see them on the web?

IESO Community Engagement's avatar

IESO Community Engagement
Jul 27, 2021 - 10:09

The presentation slide deck is posted on this event page under the title "Presentation".

IESO Community Engagement

Mike Zajmalowski's avatar

Mike Zajmalowski
Jul 27, 2021 - 10:28

Besides the policy drivers which are expected to increase load growth in the NE, do you have existing customers that are indicating growth in their demand due to the growth in their business model absent government incentives? For e.g. do you have customers that are looking to grow that currently cannot because the existing infrastructure/supply is insufficient?

IESO Community Engagement's avatar

IESO Community Engagement
Jul 28, 2021 - 10:56

This bulk planning study will consider a scenario with all the potential growth that have been communicated to us. The potential growth can be driven by existing or new customers. It is important to note that the IESO’s Connection Assessment and Approvals process will determine the final requirements for the connection of any project. We coordinate internally and work with all customers that want to connect to ensure they have sufficient supply to meet their needs.

Robert's avatar

Jul 27, 2021 - 10:32

With the upgrade completed what will the transfer capacity be for the EW Tie.

IESO Community Engagement's avatar

IESO Community Engagement
Jul 28, 2021 - 10:57

The reinforced East-West Tie has a capability of at least 450 MW. It is expected that the limitation for East to West transfer will move from the East-West Tie to the Focus Area of the NE Bulk Plan.

Daryle's avatar
Jul 27, 2021 - 10:44

When is the EWT scheduled to be in service?

IESO Community Engagement's avatar

IESO Community Engagement
Jul 28, 2021 - 10:58

The East-West Tie is scheduled to be in service Q1 2022.

IESO Community Engagement's avatar

IESO Community Engagement
Jul 29, 2021 - 09:11

Received July 28, 2021 11:59 AM by email:

Some of the bulk system constraints in the North East are due to the configuration of lines and sub-stations, will the analysis and recommendations include reviewing the configuration issues and contingency analysis limitations they impose as part of the potential solutions to maximizing as well as expanding system capacity.

IESO Community Engagement's avatar

IESO Community Engagement
Jul 29, 2021 - 09:11

IESO conducts contingency analysis when identifying system issues as well as in developing and assessing the performance of options. The contingency analysis will identify all issues and their causes. We will review all options that can optimize the network configuration and address the identified issues. If there are any configuration changes that you can specifically identify, IESO can consider those further in the options analysis.   

Anonymous's avatar
Aug 20, 2021 - 13:58

The presentation poses a number of questions (Slide 28) but provides no timeline for response. Please advise.

IESO Community Engagement's avatar

IESO Community Engagement
Aug 24, 2021 - 15:51

These questions are examples of some key considerations that will help inform how we will engage with customers, communities and stakeholders in the Northeast about our work for this bulk electricity planning initiative. Stay tuned for future updates.

Peter Drury's avatar

Peter Drury
Aug 25, 2021 - 06:43

After reviewing the webinar, I'm very disappointed in the limited scope that you've given to the ‘Focus Area’ in Slide 18. This appears to have deliberately omitted the Timmins area, and in particular Porcupine TS, as a possible source of transmission reinforcement into Northwestern Ontario. With the Focus Area that's been selected, you appear to have prejudged the outcome of the study by forcing any new reinforcement of the transmission system to originate from Hanmer TS, in the Sudbury area.

Looking at Slide 18 of your presentation, the shortest distance between the north/south 500kV system and the eastern terminal of the newly reinforced East-West Tie at Wawa TS, is from Timmins (Porcupine TS) following the approximate route of Highway 101.

A new 500kV transmission line from Porcupine TS to Wawa TS, preferably series compensated, would provide a direct connection to Wawa TS and the high-capacity East West Tie. Whilst being far less susceptible to storms coming off Lake Superior, it would also provide mutual support for the Timmins area as well as providing a more direct connection between the hydroelectric generation on the Abitibi & Mattagami Rivers and the north-west.

By reinforcing the electrical connection from the west into Wawa TS it would also allow a substantially increased benefit to be derived from the high-capacity 230kV transmission line between Wawa TS and Third Line SS, thereby reinforcing the supply to the Sault Ste. Marie area.

Rather than confining any new transmission reinforcement of the system along the much longer existing transmission corridors from Sudbury to Algoma to Mississagi to Wawa, it would seem that a new transmission connection from Timmins directly to Wawa would have considerable merit.

So my question is:

“Will the scope of the study be broadened to include a direct connection from Timmins to Wawa?”

IESO Community Engagement's avatar

IESO Community Engagement
Aug 26, 2021 - 10:35

Thank you for your feedback.

The “Focus Area” in Slide 18 is not the complete scope of the study. Per slide 22, the complete scope of the study considers the FN/S, P502X-N/S, and MISSW/E interfaces and their underlying transmission paths. While demand growth is expected across all of northern Ontario, driven largely by growth in the mineral and mineral processing sectors, the “Focus Area” is explicitly called out because we are forecasting exceptional growth in electricity demand and, as such, expecting to see a need for supply to this part of the system. When exploring options for providing that needed supply we don’t intend on exploring options only within the “Focus Area”. Your suggested option to reinforce the path from near Timmins at Porcupine TS to Wawa will be taken for consideration.

If there are any other details you would like to share for the option, please let us know.