No more nuclear can mean more wind in Ontario – gazing into the crystal ball

By: Donald Jones, P.Eng., retired nuclear industry engineer – 2013 October.

With nuclear new build in Ontario no longer part of the Ontario government’s Long-Term Energy Plan (LTEP), at least for the moment, there could be more unneeded expensive wind on the way (reference 1). With the refurbishment of Darlington starting in 2016 (reference 2) and continuing past 2020 when Pickering will close and Bruce A and B units will start their refurbishment there will be a shortfall in supply that will have to made up by new gas-fired generation. This new generation will be over and above the supply from the cancelled Oakville and Mississauga combined cycle gas turbine (CCGT) units that were relocated to property near Lennox and Lambton generating stations respectively. The additional gas-fired generation will produce greenhouse gas (GHG) emissions that will need additional wind generation, over the amount in the present LTEP, in an attempt to reduce these emissions – unlikely and alarmingly expensive (reference 3). The needed gas is increasingly coming from shale deposits fractured by large amounts of very high pressure water laced with special sand and toxic chemicals. This controversial frackgas has been said to have the same lifetime GHG emissions as coal.  Even the GHG emissions from combustion of gas may not be all that much better than from burning coal (reference 3) because of operational flexibility differences, and increases in gas prices are inevitable. Flexible nuclear would not produce any GHGs and would provide price stability.

After 2020 Pickering A and B will be closed. The two refurbished Pickering A units cannot run without Pickering B because of safety related electrical interconnections. Two Darlington units will be refurbished at the same time and likely at least two units from Bruce A and B. This means that about 6470 MW could be available from the operating nuclear units. On a hot summer peak demand day the Independent Electricity System Operator (IESO) credits hydro with around 6,000 MW for a reasonable amount of time. If there is 8,000 nameplate MW of wind by 2020 then, using the IESO capacity correction factor, we can credit wind with 1,120 MW on a peak summer day. Solar is a bit of an unknown. Even if we had around 2,000 nameplate MW by 2020 by the time the late afternoon peak rolls around this would drop, say we could credit around 200 MW. Gas and oil would be credited with 10,000 MW on a peak summer day (including the relocated Oakville and Mississauga CCGTs and Lennox). This gives a total supply of 23,790 MW. 

Since the 2006 August Ontario peak demand of 27,005 MW demand has not exceeded the 25,407 MW of 2011 July. The highest winter peak is 24,979 of 2004 December. The IESO has forecast an extreme weather peak demand of 24,954 MW for the summer of 2014. If we assume most of the low hanging conservation fruit has been picked due to high electricity prices, consider increased population, and a pickup in manufacturing and energy intensive industries from the recent Canada – European Union Free Trade Agreement, then we could say the peak power demand in 2020 may be at least 26,000 MW. The grid also needs about 1,600 MW of spinning and non-spinning operating reserve to cater for the unexpected loss of a couple of its largest generating units. Since neighbouring jurisdictions will also be affected by the hot weather they may also be stretched so we should not depend on too much help from them. The shortfall between supply and demand, that will be met mostly with new additional frackgas generation and with some demand management, could be around 3,810 MW. This is equivalent to four frackgas-fired generators of the same capacity as the relocated Oakville CCGT units. More generation may be found necessary as we move closer to 2020. There will be few communities near where the electricity is used willing to host these frackgas-fired plants and their high pressure frackgas supply pipelines (reference 4). Hotter days can be expected in the future, because of climate change, that will put up demand and may also impact hydro-electric supplies.

The government, and its vocal so called “environmentalist” (anti-nuclear) supporters, promotes the false premise that unreliable renewables such as wind are replacing coal-fired generation in Ontario. When pressed on the intermittency of wind the response is that gas-fired generation will just be providing the backup to the wind. Wrong. When X MW of coal is being replaced it is being replaced by X MW of gas not wind. Wind is totally unnecessary and is the camouflage for unsavory gas. In practice more gas is added than the coal it is replacing in order to maintain ramping capacity because CCGTs are less flexible in operation than coal. Ontario is shutting down around 7,500 MW of coal and replacing it with around 11,000 MW of frackgas and oil, including the dual-fired Lennox Generating Station and the relocated Oakville and Mississauga CCGTs.

If demand is low and wind generation high exports subsidized by Ontario’s electricity users would be maximized, privately operated Bruce nuclear units would reduce output and get paid for deemed generation, and some of publicly owned Ontario Power Generation’s hydro units would be shutdown and not get paid for lost generation. Wind would then be dispatched down and deemed generation paid for. If demand is high and wind generation is high then some wind generation may still be dispatched down to ensure that if wind generation drops fairly rapidly there is sufficient reserve (hydro short term and gas longer term) to kick in at short notice to keep the grid in balance (reference 5).

Increasing the amount of wind on the Ontario grid above this amount of generation that can be quickly made available if wind generation “suddenly” falls would mean adding quick responding simple cycle gas turbine (SCGT) units to the grid just to manage this event and would be surplus to grid requirements (reference 5). This should set a limit on the amount of useful wind the Ontario grid can accommodate. However the need for more gas generation to be available around 2020 to cater for nuclear closures and refurbs will give the government, and its “green” anti-nuclear lobby, the excuse it needs to add at least 3,810 MW of unreliable new wind generation to the grid (about 1,900 new wind turbines) under the pretense that wind is replacing the supply lost from the nuclear refurbishments and closures, with frackgas just as “backup” of course.

As was the case with the coal-fired plant closures the replacement 3,810 MW will be provided by reliable frackgas not by unreliable wind and frackgas will provide the support any new wind needs even if it is not needed by the grid. Rural communities are already up in arms about wind turbines being installed near them. If this is what the government intends to do it then it will become apparent if the new gas-fired generation is made up of SCGTs as well as CCGTs with bypass stacks to enable simple cycle operation that can get on line quickly if wind generation drops. Given the present composition of generators on the grid there is little flexibility to absorb even the planned 10,700 MW of wind/solar/bioenergy never mind an extra 3,800 MW or so.


1. Failure to condemn wind may condemn Darlington B, Don Jones, 2012 February, article 13 of

2. Ontario’s Darlington B must be on line before 2020 and must be CANDU, Don Jones, 2012 August, article 17 of

3. IESO – will Ontario’s wind turbine power plants reduce greenhouse gas emissions?, Don Jones, 2010 August, article 3 of

4. Dash for Gas: will Ontario repeat the UK’s mistake?, Don Jones, 2013 May, article 27 of

5. More wind means more risk to the Ontario electricity grid, Don Jones, 2011 January, article 6 of


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