Delivering Transparency and Trust

Overview of the Bruce Power Contract

Bruce Power is Ontario’s lowest cost source of nuclear power, producing approximately 30 per cent of the province’s electricity. The company is required under its contract with the Independent Electricity System Operator (IESO) to sell all of its electricity output at a fixed price.

Under separate agreements, Bruce Power leases the facility from Ontario Power Generation (OPG) and through this lease is required to assume all costs associated with its operation, life extension, services and through the lease payments fund the long-term liabilities including the rental of the facility. This lease arrangement is designed to ensure all costs related to Bruce Power’s operation are assigned to the company and included within its price of power.

Ontario Ratepayers to Benefit from Federal ITCs under Bruce Power Agreement

Bruce Power and the Independent Electricity System Operator (IESO) have executed an amendment to the ‘Amended and Restated Bruce Power Refurbishment Implementation Agreement’ (ARBPRIA), to incorporate the introduction of Investment Tax Credits (ITC) announced by the Government of Canada.

ITCs were formally outlined in the 2023 budget by the Government of Canada, to address impacts from the implementation of the Inflation Reduction Act in the United States. The purpose of this amendment is to adjust the power price mechanics so that electricity ratepayers receive the benefit of the Government of Canada’s announced 15 per cent refundable ITC for eligible investments in non-emitting electricity generation systems. While Ontario electricity ratepayers will benefit from these ITCs, Bruce Power and its investors in these critical Projects will not be adversely impacted.

Through this amendment, clean electricity ITC’s applicable to Bruce Power’s investment program inclusive of Major Component Replacement (MCR) and Asset Management (AM) will fully benefit Ontario ratepayers and reduce electricity system costs. Specifically, these ITCs will be deducted directly from investment costs subject to power price adjustments under the IESO agreement with Bruce Power.

Bruce Power continues to be the largest private investor in the provinces’ electricity generation infrastructure and remains committed to doing so in a manner that is cost effective. In fact, Bruce Power is the lowest cost nuclear generation in Ontario by a margin of approximately 15 per cent. In September 2023, Bruce Power successfully returned Unit 6 to service from its MCR Project ahead of schedule and under budget.

The Government of Canada will be finalizing provisions related to ITCs in 2024.

Bruce Power amended its long-term contract with IESO

In December 2015, Bruce Power amended its long-term contract with the IESO, an organization established under the Electricity Act to manage Ontario’s electricity system. In this capacity the IESO enters into contracts for electricity output with various supply sources across the province. In Ontario, virtually all electricity generated in the province is purchased at rates set under contract with the IESO or through prices set by the Ontario Energy Board (OEB).

When this long-term contract was announced in 2015, Bruce Power issued this news release, a backgrounder along with key elements of the contract, named the Amended and Restated Bruce Power Refurbishment Implementation Agreement.

Central to this contract is the 13-year Major Component Replacement (MCR) Project, which aims to extend the life of Units 3- 8 for an additional 30 years. Upon completion, the MCR will allow the Bruce Power site to produce electricity through to 2064.

In 2017, the Financial Accountability Office (FAO) undertook a review of the contract at the request of the Ontario Legislature. The FAO concluded that “there are currently no alternative generation portfolios that could provide the same supply of low-emissions baseload electricity generation at a comparable price to the Base Case Nuclear Refurbishment Plan.” In addition, as to pricing, the FAO estimated that the contract would result in Bruce Power supplying a significant proportion of Ontario’s electricity demand from 2016 to 2064 at an average price of $80.7/MWh in 2017 dollars.

Our Refurbishment Implementation Agreement was developed to ensure Bruce Power assumes responsibility for the operation and life extension of the units, ensuring a stable supply and price certainty of electricity generated at the site.

This page is set up to provide information to the public and interested stakeholders on this important arrangement with the IESO. Bruce Power is committed to making information available and answering questions. Inquiries can be directed to

As a private sector company, Bruce Power enters into commercially competitive arrangements and arrange financing to deliver on our obligations. There is some commercially sensitive information that has to remain confidential to maintain that competitive tension. However, the company continues to endeavour to answer any questions and provide information of interest to the public and stakeholders.

Cost of Electricity from Bruce Power

Bruce Power receives a fixed price for its electricity generation that is inclusive of all its current costs and funding of future decommissioning liabilities in the Bruce Facility. As previously noted, the average price over the life of the contract was estimated by the IESO to be $77/ MWh (in 2015$).

To learn more about the power price calculation under the contract, please refer to the IESO document Bruce Power Nuclear Generating Station PPA Key Elements

Estimated prices from the financial model
as at the effective date of the ARBPRIA

Price on Jan. 1 of the year Projected (2015$) Actual (2015$)
2016 66.73 65.39
2017 65.63 64.02
2018 65.53 63.28
2019 65.45 63.10
2020 72.38 71.78
2021 72.14 71.46
2022 71.92 71.13
2023 76.39 76.23*
2024 76.10
2025 78.67
2026 79.33
2027 82.21
2028 81.82
2029 85.35
2030 84.92
2031 87.55
2032 87.77
2033 87.29
2034 86.85
2035 87.06
2036 86.62
2037 86.19
2038 86.15
2039 85.75
2040 85.36
2041 85.51
2042 85.13
2043 84.76
2044 84.75
2045 84.41
2046 84.06
2047 83.88
2048 83.56
2049 83.26
2050 83.07
2051 82.79
2052 82.50
2053 82.27
2054 82.02
2055 81.79
2056 81.56
2057 81.34
2058 91.13
2059 80.94
2060 80.75
2061 80.57
2062 80.41
2063 80.24

The initial forecasted price of the contract is adjusted from time to time. For example, the price is increased as capital is invested to fund the MCR Program consistent with the contract. There are also price adjustments for several variable factors such as inflation and Asset Management capital investments.

The table referenced above reflects the projected contract price by the IESO between 2016 and 2063 (in 2015$). It also illustrates the actual price realized to date on an annual basis (in 2015$).

It is important to note that $200 million in operational efficiency sharing announced by Bruce Power in January 2019 was paid to the IESO. This cost sharing that arises pursuant to the contract has not been credited in this price analysis. Please see this news release outlining Bruce Power’s $200 million in efficienciesWe are not aware of any other contracts that require payments back to the IESO for improved performance.

The IESO also hosts a Price Overview Section on its website, which contains historical data on electricity prices, as well as the impact on the Global Adjustment (GA) by each generation type, including Bruce Power Nuclear.

The price paid for electricity from Bruce Power, as of April 1, 2023, is estimated to be $93.72/MWh. This is inclusive of the $84.72/MWh base price, in addition to an estimated $9.00/MWh** which is reimbursed for front-end and back-end fuel costs. (**does not include 2023 front-end and back-end fuel costs associated with Unit 6 MCR fuel load and Unit 3 MCR defuel).

As of April 1, 2023, the price of electricity from major sources of electricity in Ontario is as follows:

Source of electricity Estimated Annual Supply Price Paid for Electricity (cents/kWh) Source of information
Hydroelectricity 26% 6.1 RPP Price Report Ontario Energy Board
Bruce Power Nuclear 29% 9.4 RPP Price Report Ontario Energy Board *
OPG Nuclear 20% 10.9 RPP Price Report Ontario Energy Board *
Gas Generation 13% 11.3 RPP Price Report Ontario Energy Board
Wind 10% 15.4 RPP Price Report Ontario Energy Board
Solar 2% 50.2 RPP Price Report Ontario Energy Board
Bioenergy 1% 25.8 RPP Price Report Ontario Energy Board

Bruce Power takes great pride in ensuring that it is delivering Ontario customers low-cost, reliable, GHG-emissions free power. We are the source of half of Ontario’s nuclear generation, and the lowest cost source of nuclear energy in the province.

Life Extension Capital Program

The Bruce Power Contract contemplates the life extension of up to six nuclear reactors which is achieved through Major Component Replacement (MCR), commonly referred to as refurbishment, and Asset Management (AM).

Major Component Replacement (MCR)

The timing of the completion of the Units 3-8 MCR Program has been staggered, designed to optimize the operational life of each unit and to meet electricity supply needs.

No later than 15 months prior to the scheduled refurbishment of each reactor unit, Bruce Power is required to provide the IESO with a fully scoped refurbishment cost and schedule for the unit. The IESO then has until 12 months before the refurbishment begins to verify the estimate. The IESO has a team assigned to the Bruce Power site to monitor the development of these estimates consistent with the contract and project management best practices by Bruce Power in the facility.

Once the IESO verifies the fully scoped refurbishment cost for each unit, the Bruce Nuclear price will be adjusted on April 1 of each calendar year to reflect the additional capital investments.

For certainty and off-ramp purposes, the contract contains and Bruce Power agreed, to a cost and schedule estimate for each refurbishment project. Consistent with Project Management principles, this estimate had an acceptable range for cost and schedule based on the state of the estimate and the sequential nature of the program. Under the contract, subsequent MCRs are expected to improve on cost and schedule by building on lessons learned and experience.

Bruce Power is responsible for all capital costs related to the MCR program and the risk of executing the project from a cost and schedule perspective once it receives approval to proceed.

Through Bruce Power’s Upside Sharing Arrangement with the IESO, if Bruce Power is able to deliver:

  1. better than planned MCR performance and/or
  2. better than planned operations performance 

A portion of the savings are to be returned to Ontario customers. For the first unit refurbished, 50 per cent of the savings versus the locked in cost estimate for the refurbishment will be returned to ratepayers, while 75 per cent savings will be returned for the second unit refurbished, and incremental savings will be returned for the third through sixth units refurbished.

Early in 2019, through this agreement Bruce Power provided $200 million in savings that were returned directly to Ontario ratepayers.

In early 2024, the IESO verified that Bruce Power met the terms and conditions of the company’s Basis of Estimate to proceed with Unit 4 Major Component Replacement (MCR) Project in early 2025. Building on the success of the company’s first MCR project in Unit 6, which was returned to service in 2023 ahead of safety, cost and schedule targets, the Unit 4 MCR outage will be Bruce Power’s third as it renews Units 3-8 over the next decade. Investment Tax Credits (ITCs) will be deducted directly from these investments and savings will go directly to Ontario families and businesses through our reduced price of power.

Asset Management

The Bruce Power Life-Extension Program is made up of the Major Component Replacement (MCR) project, which began construction in 2020 and will extend over a 13-year period, as well as an Asset Management Plan.

Bruce Power’s Asset Management Plan for Units 3-8 is an essential part of the continued safe and reliable operation of the site until 2064.

Asset Management includes the ongoing inspection, maintenance, replacement and refurbishment activities not included in MCR necessary to extend the life of components. Asset Management activities will be executed before, during and after the MCR outages. Like MCR costs, the costs of asset management activities are recovered through the contracted price of power.

The alignment of the MCR scope with asset management plans will support Bruce Power’s goal for safe and reliable long-term operation while helping to ensure project success by focusing the scope of MCR work and optimizing the life of other assets.


In 2013, the Province of Ontario’s Long Term Energy Plan (LTEP) established the policy framework for future refurbishments including a requirement to establish realistic off-ramps. Given this, the Bruce Power contract with the IESO established two types of off-ramps for the province:

  • MCR Off-ramps provide the IESO with the option to not proceed with the subject refurbishment or all future refurbishments if the estimates provided by Bruce Power prior to each refurbishment exceed certain cost or duration thresholds. The cost threshold is a 30 per cent increase over the refurbishment cost amount that is reflected in the base-case nuclear price estimate.
  • Economic off-ramps can be exercised prior to the third and fifth MCR. Economic off-ramps provide the IESO with the option to terminate all remaining refurbishments due to changes in supply or demand in electricity have resulted in there no longer being a need to refurbish the remaining units or their being more economic alternatives to the refurbishment of all the remaining units.

In April 2022, Ontario’s Minister of Energy, Hon. Todd Smith, supported by Hon. Lisa Thompson, MPP and Bill Walker MPP, directed the IESO to waive the first economic off-ramp available to the IESO before 2024 included in the Amended and Restated Bruce Power Refurbishment Implementation Agreement (ARBPRIA).

This reaffirmed the government’s continued support for the role of Bruce Power nuclear in meeting the province’s growing demand for low-cost, reliable, clean electricity, while supporting Net Zero goals. Bruce Power’s role in the production of medical isotopes and continued work to achieve increased site output through Project 2030 were also noted. The Minister’s Directive can be found here.

Bruce Power will still be subject to a second economic off-ramp prior to the fifth Unit (Unit 7 in 2027) and each of Bruce Power’s future MCR’s (Unit’s 4,5,7 and 8). In total, there are five remaining off-ramps over the next ten years Bruce Power will be subject to under the agreement.

Bruce Power assumes the risk of any cost overruns during the execution of the refurbishment. Ontario is protecting customers by strictly controlling the cost and timetable of the refurbishments to ensure that they are delivered on time and on budget.

Decommissioning, Fuel and Waste Costs

The price paid for Bruce Power nuclear electricity is fully inclusive of all costs, including capital investments that have been made, funding for fuel, waste and decommissioning liabilities and every element of the company’s operation. As outlined above, agreements with OPG related to the lease and other services are aligned with Bruce Power’s contract with the IESO to ensure the price is fully inclusive of all costs.

Nuclear fuel costs are inclusive of the entire cradle-to-grave nuclear fuel life cycle from extracting uranium ore from the earth to power production in a nuclear reactor to permanent disposal of the resulting spent nuclear fuel.

This includes front-end costs which consider the portion of the nuclear fuel cycle leading up to electrical power production in a nuclear reactor as well as back-end costs which encompass, at minimum, on-site pool storage and long-term waste disposal. Unlike natural gas prices, which are very sensitive to market changes, nuclear fuel costs are more predictable and stable. Bruce Power’s fuel costs reflected in the amended agreement are set through a long-term procurement strategy and represent approximately 12 per cent of the 2016 Bruce Nuclear price. 

Additionally, through Bruce Power’s site lease with OPG, the company will continue to fund decommissioning and waste management costs.

The cost to manage these liabilities will be determined through the Ontario Nuclear Fund Agreement (ONFA) process and are reflected in Bruce Power’s price of power.

This ONFA established dedicated funds to cover the cost of long-term nuclear waste management, fuel costs and the cost of decommissioning so they’re not passed on to future generations.

To learn more about decommissioning and fuel costs see here.

Nuclear Waste and the MCR Program

Bruce Power manages many different forms of waste, including:

  • Radioactive
  • Hazardous (oils, chemicals, lighting lamps and ballasts – some of which are recyclable)
  • Recyclables (glass, cardboard, plastic, paper, metal, wood, batteries and electronics)
  • Organic (compost)
  • Landfill

Bruce Power manages radioactive waste in partnership with OPG. We comply with all waste regulations and requirements of the relevant federal authorities. Bruce Power has always taken an active role for many years to reduce all forms of waste. From an environmental and financial standpoint, waste reduction is good for our company and for the communities we touch.

Our philosophy employs a whole life-cycle approach in that we reduce waste, generate less waste at the company level, find opportunities to reuse products (on-site, off-site donations, auction), and implement recycling programs that are available in the ever-changing recycling market.

For more information about nuclear waste specifically related to the MCR program please see here.

Evaluating the Bruce Power Contract

Financial Accountability Office – Nuclear Refurbishment Report

The FAO provides independent financial analysis to the provincial legislature.

In 2017, the FAO reviewed how the Nuclear Refurbishment Plan will impact ratepayers and the province, and to identify how financial risk is allocated among ratepayers, the province, OPG and Bruce Power.

Key Findings

  • The report concluded that there are currently no alternative generation portfolios that could provide the same supply of low-emissions baseload electricity generation at a comparable price to the Base Case Nuclear Refurbishment Plan.
  • To the extent that alternative generation options emerge over the life of the Plan, opportunity cost risk is mitigated by economic off-ramps in the Bruce Contract and the Province’s ability to terminate Darlington Nuclear Generating Station refurbishment.
  • The FAO estimates that the Plan will result in nuclear generation supplying a significant proportion of Ontario electricity demand from 2016 to 2064 at an average price of $80.7/MWh in 2017 dollars.

Force Majeure and the Bruce Power Contract

As outlined in the Amended and Restated Bruce Power Refurbishment Implementation Agreement  Bruce Power and the Independent Electricity System Operator (IESO) under certain circumstances may invoke Force Majeure (FM) which is a typical element to contractual agreements of this nature.  In this case, FM includes epidemics and pandemics.

If Bruce Power is unable to perform or is delayed in performing its obligations  and determines the reason for such inability or delay was an act, event, cause or condition that it believes was an event of FM, then as agreed to in our contract, we may invoke FM. 

Notification of FM must be made within 20 days of determining for the occurrence of a FM event.

By invoking FM, Bruce Power is excused and relieved from performing or complying with its obligations under the contract.

Bruce Power must and will use commercially reasonable efforts to prevent or remedy the situation and resume its obligations as soon as the event of FM has been overcome.

Current Status

On March 25, 2020, Bruce Power declared FM under its contract with the Independent Electricity System Operator (IESO) due to the impact of COVID-19. The FM notice covered the Unit 6 Major Component Replacement (MCR) and certain eligible FM Asset Management Work.

At the time the FM was declared, the Unit 6 MCR Program was ahead of schedule with the early completion of the reactor defuel window. Given the pandemic, the Unit 6 MCR program was scaled back and limited to essential tasks related to plant safety and system integrity.  Work has since resumed on MCR activities and is back on track with strict prevention measures in place to protect workers and to ensure adequate provisions for ongoing operations within the facility. 

Ontario Chamber of Commerce report

In 2019, the Ontario Chamber of Commerce released an economic impact assessment of the MCR Project undertaken as part of Bruce Power’s Life-Extension Program.

The report, Major Component Replacement Project Economic Impact Analysis, reveals that the 13-year-long MCR Project would be of significant benefit to the economy through economic impact, GDP increase, tax revenue, and opportunities for local workers and industry.

For more information see here Major Component Replacement Project Economic Impact Analysis.

Canadian Manufacturers and Exporters report

In 2018, the Canadian Manufacturers and Exporters (CME) released a report that looks at how extending the life of the Bruce Power site to 2064 will positively impact the people of Ontario through low-cost, reliable, carbon-free electricity, as well as the continued investment in jobs and the economy.

The report – a joint effort between the Canadian Manufacturers & Exporters, the Provincial Building and Construction Trades Council of Ontario, and Bruce Power – shows that 22,000 Ontario jobs will be created and sustained directly and indirectly through the Bruce Power Life-Extension Program every year, while $4 billion in domestic economic benefit will be realized through the direct and indirect spending on operational equipment, supplies, materials and labour income annually, 

For more information see here – Powering Innovation, Jobs and Economic Growth

Other resources:

Additional IESO Resources