I recently read an entry on Wayne Gulden’s Wind Farm Realities website reviewing some figures for the Vestas V82 – 1.65MW capacity industrial wind turbine. The statement that stuck with me was:
… when the wind doesn’t get above 3.5 m/s – typically there’s a MINUS 50kw of production. This is power that must be supplied from the grid just to keep the turbine in business. And 50kw seems to be what the turbine uses to stay alive in good weather. In the winter it gets slightly higher – the highest negative numbers were in the 80 kw range.
I decided to investigate the performance of an industrial wind turbine project in Ontario comprised of 110 of the Vestas V82 turbines; Enbridge’s Underwood turbines in Bruce County.
110 turbines potentially each drawing 50kW means that at times when all Enbridge’s turbines are still, the draw would be ~5.5MW. In the parlance of the Ministry of Energy, and the renewables lobby, a draw of 5.5 MW is enough to prevent power being provided to over 4000 homes.
In Ontario, we know that wind is least productive in July – so the topic of how much “parasitic” load is present when turbines are unproductive is particularly relevant here.
The turbines’ manufacturer, Vestas, produced a Life cycle assessment of the V82-1.65 MW (the LCA) showing “energy balance” is achieved in 7.2 months of production. The “energy balance” is how long the turbine will take to generate the amount of energy consumed in production and disposal.
read more: Cold Air, Aug 2 2014