New technologies are transforming the way we produce and use electricity. The IESO is at the forefront of this change, driving and guiding the electricity sector’s evolution. See how Ontario’s power system is transforming.
The IESO plans the electricity system to ensure Ontario’s energy needs are met. This includes coordinating the construction of transmission lines and facilitating the development of new power plants. Broad and effective engagement with communities and partners is necessary to balance the needs of homes and businesses with the overall needs of the electricity system.
Regional Planning
Ontario is divided into 21 regional planning zones that each undergo a five-year regional planning cycle. Regional planning looks at the electricity needs of each region, considering energy conservation, electricity generation, distribution infrastructure and innovation to meet those needs.
Provincial Planning: Provincial electricity planning, referred to as bulk planning, focuses on province-wide needs. Bulk planning considers the location of large power plants, the capacity of high-voltage transmission lines and Ontario’s grid connections with neighbouring jurisdictions.
Regional Planning: Ontario is divided into 21 regional electricity planning zones. The IESO assesses each zone’s electricity needs during the regional planning process, considering energy efficiency, electricity generation, infrastructure and opportunities for innovation. The IESO leads the regional planning process, working closely with Local Distribution Companies (local hydro companies) and transmitters.
Local Planning: Electricity is delivered directly to households and businesses across Ontario by Local Distribution Companies (LDCs), or local hydro companies. Nearly 60 LDCs are actively involved in forecasting and planning for their communities’ energy needs and maintaining local electricity infrastructure. The IESO is not responsible for local planning, but the work of LDCs is integrated into broader regional planning efforts.
Forecasting Ontario's Energy Needs
The IESO uses forecasts to inform future infrastructure planning and supply procurement. These forecasts consider many variables, including:
The impact weather could have on demand
The sector’s ability to make - and deliver - enough power to Ontario’s communities
Future electricity demand drivers, such as the opening of new manufacturing plants, electric vehicle uptake and economic sector growth
These forecasts are regularly updated as new information becomes available to signal new project and investment opportunities.
Annual Planning Outlook
Provides a 20-year overview and assessment of Ontario’s electricity system and its ability to meet demand.
