Ontario's Independent Electricity System Operator (IESO) has released its Reliability Outlook. The Outlook states that Ontario's longer-term reliability picture is positive. Ontario's focus should be ensuring that generation, transmission and demand-side initiatives are implemented in time to meet needs as well as address any integration and operational challenges in the future.

Since the last report, there have been delays to the scheduled in-service dates for Phase One of the Goreway Generating Station in the Greater Toronto Area (GTA) and unplanned outages at the Pickering Nuclear Station which resulted in more than 1,500 MW of supply being unavailable. Aside from this outage, there was no major disruption in service.

New Supply

Almost 4,000 MW of new gas-fired supply is expected to come into service over the next three years. This new supply is sourced from the Greenfield Energy Centre near Sarnia, the Portlands Energy Centre in Toronto, the Sithe Goreway facility in Brampton and the Halton Hills Generating Station near Milton. In addition, approximately 630 MW of grid-connected wind power is also expected to come into service before the end of 2008.

With 475 MW of wind resources currently being installed, it is expected that this type of generation will take on an increasingly significant presence in Ontario's future supply mix. Challenges could arise from the intermittent nature of wind and demand peaks. The IESO's Wind Integration Standing Committee has developed recommendations and implemented decisions to reduce barriers to the successful integration of wind generation into the system.

Operability of the Power System

Previously, the IESO had identified operability as a key parameter for future supply mix. Since then, the OPA has submitted the Integrated Power Supply Plan (IPSP) to the Ontario Energy Board (OEB) for approval. The IESO has also discussed operability matters with the Ontario Power Authority (OPA) through the preparation of the IPSP and will follow up with an operability review, simulating future operating conditions under the proposed supply portfolio to assess whether there is enough operating flexibility. The findings will be released shortly.


Timely implementation of proposed transmission facilities still remains a key component for addressing future reliability needs. Over the next decade, enhancements will be implemented in Southwestern Ontario, Northern Ontario, the Greater Toronto Area, York Region, South-Central Ontario, and many other places. The development of new transmission across Southwestern Ontario still remains a high priority. It is expected that new facilities from Bruce to Milton will deliver the full capability of the Bruce refurbishment and the regions expected new wind resources. Transmission enhancements are also required to enable the replacement of the coal-fired stations with cleaner resources.

Conservation and Demand Management

The Ontario government has set aggressive load reduction targets for the near future, with a target of 2,700 MW reduction in peak demand by 2010. It is expected that Ontario's Smart Metering Initiative can also help enhance the reliability of the power system. This initiative calls for smart meters to be installed in homes and small businesses throughout the province by 2010.

Approvals Process

The IPSP filing with the OEB has represented a major milestone in Ontario's supply program. However, the IESO remains concerned about the uncertainty surrounding the length of the approvals process. Substantial work is currently underway by a number of stakeholders to address the inefficiencies in the process. The improvements should ensure appropriate public review of energy and other infrastructure proposals.

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