“What is the wind speed for optimal generation? I know of one that requires constant 25 mph wind.”
See fig. 2.
In general, wind turbines begin to produce power at wind speeds of about
6.7 mph (3 m/s). A turbine will achieve its nominal, or rated, power at approximately 26 mph to 30 mph (12 m/s to
13 m/s); this value is often used to describe the turbine’s generating capacity (or nameplate capacity). The turbine
will reach its cut-out speed at approximately 55 mph (25 m/s). When wind speeds exceed this, the turbine will
stop power production to protect itself from potentially damaging speeds. Variability in the wind resource results
in the turbine operating at changing power levels. At good wind energy sites, this variability results in the turbine
operating at approximately 35% to 40% of its total possible capacity over a year
35% to 40% in a year? Wow, that much?
/s