IESO publications provide information and insight into various aspects of Ontario's electricity sector, including 18 month assessments of system adequacy, how businesses can manage their electricity costs, developments in Ontario's electricity market, and more.

To order a hard copy of one of these publications, please email at

Serving Ontario's Electricity Consumers

Serving Ontario's Electricity Consumers

Ontario's IESO works to ensure sufficient electricity is available whenever and wherever it's needed. Ensuring there is enough energy to meet demand is an ongoing and highly complex process, requiring the close coordination of all parts of the system.

En français


Ontario Planning Outlook

Ontario Planning Outlook

The IESO’s Ontario Planning Outlook (OPO) is a technical report that provides a 10-year review (2005-2015) and a 20-year outlook (2016-2035) for Ontario’s electricity system.

En français

Annual Report Cover

IESO’s 2016 Annual Report: Reliability in a Changing Sector

The IESO’s 2016 Annual Report, Reliability in a Changing Sector, takes a look at some of the core initiatives the IESO undertook in 2016, as well as a look forward to the coming year and beyond. It describes how the IESO will continue to provide superior reliability in a changing environment, create a culture of conservation in Ontario and renew its electricity markets, all while working with the IESO’s stakeholders and communities.

En français

Demand Response Brochure

Demand Response

Demand response is a smart approach to managing energy costs. Learn more about the many ways the IESO is expanding the possibilities for demand response in Ontario.

Find out more about Demand Response.

The Bottom Line on Energy Management

A Guide for Business

Understanding how and when your facility uses electricity will help your business manage its energy needs and meets its energy targets. The IESO brochure, The Bottom Line on Energy Management: Making Ontario’s Electricity Market Work for Your Business explains how your company can reduce electricity costs with more efficient energy use. Featured in the brochure are case studies of energy managers who are taking control of their organization’s energy use; an explanation of your electricity bill; how you can generate new revenue through demand response, and more. Download a copy of the report or request a free printed copy from

18 Month Outlook

18-Month Outlook (Current Report)

The 18-Month Outlook reports on the near-term reliability and operability of Ontario's power system. This quarterly publication assesses the adequacy of available supply and transmission to meet forecasts for Ontario's demand over the upcoming 18-month period. It is used by market participants and industry stakeholders to inform their business decisions and to help plan equipment outages.

See all 18-Month Outlook reports in the Document Library (select 18-Month Outlook filter).

Conservation Progress Report

Quarterly Conservation Progress Report (Current Report)

The Progress Report highlights the results of conservation programs by quarter, including savings for residential, business, and industrial programs, and the number of program participants. Fourth quarter
reports also detail savings results and program participation totals for the entire year.

Find more information on the IESO's commitment to conservation and energy efficiency in the 2015 Conservation Results Report.

See all quarterly and yearly conservation reports in the Document Library.

 contracted electricity supply report cover

Quarterly Contracted Supply Report (Current Report)

The Progress Report on Contracted Electricity Supply provides a status of the IESO’s contracted generation capacity in both the Ontario transmission and distribution grids.

See all quarterly contract supply reports in the Document Library.