Planning: Forecasting Needs

Planning is essential to a reliable, sustainable electricity future. The IESO plans and prepares for Ontario's electricity needs by assessing energy needs for the power system of today and tomorrow, as well as planning to ensure electricity will be available when and where it is needed. The responsibility includes broad engagement with stakeholders and communities across the province. It is an iterative process that must consider short-, medium- and long-range electricity needs as well as impacts on cost, reliability, the environment and others.

Forecasting Ontario's Energy Needs

Forecasting electricity demand is a complex exercise that identifies future electricity system needs and the factors that influence them. It also provides insights into electricity system changes that will be required to meet Ontario’s energy needs and ensure the continued reliability of the provincial grid.

The IESO’s forecasts are grounded in data analysis and consider the impacts of many variables on demand, including:

  • The day of the week – including special events and holidays
  • Weather impacts
  • The grid’s ability to make - and deliver - enough power to Ontario’s communities
  • Sources of demand, such as the opening of new manufacturing plants and electric vehicle uptake
  • Government policies and conservation efforts
  • Historical energy use patterns

The long-term forecast of Ontario's electricity system is summarized in the IESO's Annual Planning Outlook (APO). The APO forecasts electricity demand, assesses the reliability of the electricity system and assesses supply to meet them the province's energy needs.

Bulk system planning

Bulk system planning focuses on the electricity resources that transmit energy from the generation source to local distribution companies across the province. The IESO’s bulk system planning processes address provincial electricity needs and consider the impacts of various factors on the electricity system, including policy directions, the supply/demand balance, operability requirements and others. The IESO is seeking feedback from stakeholders and communities to further evolve forecasting through the bulk system planning process.

Regional planning

Regional planning considers local electricity priorities within each of the province’s 21 electricity planning regions. This process considers each region’s unique needs, priorities and preferences. Options to satisfy local demand may include generation, transmission and distribution, and/or other innovative resources or solutions.

Get involved with power system planning for your region.