Conditions are right for wind turbines to generate electricity about 30% of the time. When they’re not generating electricity, wind turbines are in stand-by mode & actually consume power from the grid. However, let’s assume that wind turbines generate more electricity than they consume. The question is: do they reduce CO2? Consider the amount of CO2 generated by each of these processes:
- All wind turbines are backed up by fossil fuels, usually natural gas
- Each turbine/transformer requires power lines, that’s an estimated 6,700 km of new transmission lines for Ontario
- Each turbine requires an access road, that’s 6,700 new roads or 4,500 kilometres of wind turbine access roads
- Ontario’s turbines require 670,000 metric tons (tonnes) of gravel for access roads
- Ontario’s turbines require 9,648,000 (almost 10 million) tonnes of concrete for foundations
According to the developer of one of Ontario’s first projects, for each of their 1.8 megawatt wind turbines:
- the tower contains 195 tonnes of steel
- the nacelle contains 67 tonnes of material
- the blade & hub assembly contains 37 tonnes of composite material
So the average turbine in Ontario requires about 300 tonnes of material. Therefore for all of the turbines planned for Ontario require 2,000,000 (2 million) tonnes of material to be mined, processed & transported, all producing CO2.
In order to determine whether wind turbines reduce CO2, one must consider each & every activity of the wind industry, including travelling to conferences, visiting landowners, lobbying MPPs, setting up offices, marketing materials etc.