Bulk Plan Design

Bulk planning considers the technical needs of the electricity system at a provincial scale, alongside projected electricity demand, driven by factors such as population growth and economic development. This helps ensure Ontario's electricity system can continue to meet the province's evolving needs reliably and efficiently. Bulk plans evaluate:

  • location of large generating stations (e.g., nuclear, hydro)
  • capacity of high-voltage transmission lines
  • transmission connections with neighbouring jurisdictions
  • economic and population growth trends, and other factors

Inputs

A bulk plan is informed by several core studies and policy documents:

Process

The IESO follows a structured, four-phase approach in the develop of a bulk plan:

  1. Demand Forecasting: How much electricity will be needed in the future?
  2. Needs Assessment: Can the current system meet future demand?
  3. Options Analysis: What solutions can address future needs?
  4. Recommendations: What actions are required to ensure long-term reliability?

The IESO’s bulk system planning process also includes the following elements:

  • Transparency through regular engagement, including sharing high level information on study scope, assumptions and progress throughout the planning process.
  • An integrated plan that evaluates both wire and non-wire options to address identified system needs, providing clarity on how different options are assessed and how recommendations are developed.
  • Recommendations that will inform ongoing system assessments and resource procurement activities.
  • For more information, refer to the Bulk Power System Planning Process – High-level Design Overview

Engagement

Community and stakeholder engagement is a critical component of bulk electricity planning. The IESO works with communities and stakeholders across Ontario to ensure planning decisions reflect local priorities and perspectives. Meaningful engagement helps generate insights that strengthen planning outcomes and support the successful implementation of recommendations.

The IESO's External Relations Engagement Framework provides a set of principles that reflect the needs of the electricity sector, communities, and the broader economy. These principles ensure diverse perspectives are considered and help strengthen the IESO's planning and decision-making processes.

In addition, the Indigenous Engagement Framework guides our work to develop meaningful and trust-based relationships with Indigenous communities. We recognize and respect the diverse cultural histories, the connections to the land, and the Canadian constitutional rights of Indigenous peoples, which is reflected in the framework.

Related Information