Ontario Wind Farm Productivity and Variability by In-service Year

This post provides data current to June 30, 2010 on the productivity and variability of output of Ontario’s wind farms. The tendency of more productive wind farms to produce power with greater annual variability of output is observed. An error in the data reported in the April 6, 2010 edition of the report with respect to Prince Farm is noted and corrected in this edition. The life-to-date capacity factor of Ontario’s large wind farms considering only full power years is 29.0%.

PDF link: ontario-wind-farm-productivity-and-variability-by-inservice-year


  1. Interesting data. From what I’ve read, 30% is the magic capacity factor for a turbine to be profitable. Most of the farms in your list were below that.

    The wide variability should also be of considerable concern to potential investors. If the project starts operations in a down year, the whole investment will be swimming upstream for some time. Investors could be forced to put up more cash to pay off lenders until cash flows improve.

    • The price for wind generated power is high enough in Ontario that owners of low-performing wind farms, like Amaranth (near Shelbourne), were still adding capacity even before the huge increase in payout rates now in place under the Green Energy Act. A wind power building boom in Ontario appears imminent.

      Ontario doesn’t have enough years of actual production data to be able to assess the trends in year-to-year variability of output without relying on historic wind-speed data and modeled output. Does anyone have data on this?

      Wind producers are completely shielded from the financial consequences of the extreme hourly variability of output. Responsibility for those costs is directly on consumers.

  2. well that sounds great but we should of expected it. paying the buy-in subsidies, and paying for fluctuating, energy production that is going to be supported by natural gas. which is good to base load with because it can only go down in price right? (sarcasm)

  3. Wind energy profitable at 30% capacity factor? Rubbish! Unless you include all of the tax money they are fed as part of their so called “profitability.”

    Wind costs $2 Million per nameplate mW to install plus operating expenses.
    30% x 8,760 hours per year x 1 mW = 2,628 mWh per year.

    At $100 per mWh, that’s a quarter million a year per in gross revenues – assuming you can sell the stuff for that rate without government sticks and carrots. So you can break even in eight years at zero percent interest and NO OPERATING OR MAINTENANCE EXPENSES. So no royalty for land owners, no taxes, no maintenance guys, no trucks, no management….

    BTW, I have followed IESO hourly wind gen reporting for two years, and there is NO WAY the figues in the chart are accurate according to the daily reports I have viewed and saved from the IESO site. Something is clearly amiss.

  4. Tom Stacy claims that my calculations of wind farm productivity are inaccurate. Anyone seeking to verify my calculations can contact me at tom.adams.energy(at)gmail.com for additional detail on the methodology and input data.

  5. People can always check my paper “Watts With the Wind” at the Wind Concerns site.

    I have done similar calculations and have no issues with your presentation. I suspect that our numbers agree as best as they can since I use calender years vs your “in-service” years.

    Anyone who doubts the chart should download the data from IESO and process it. It’s not that difficult.

Comments are closed.