calcWIND works "forward": it accepts estimates of the "wind regime profile" and converts them into an estimate of (1) cost per kWh and (2) break-even point. There are info buttons that describe where the number as shown came from. calcWIND optionally exports a *.txt file for subsequent use in a spreadsheet. There is embedded email by which to advise the developers of math errors (such as in the Weibull Probability Distribution or the Present Value function), bugs, and suggestions for improvement.
calcWIND also works "backward": once a turbine is defined, it accepts an output denominated as kWh, MWh, GWh, or as TW and returns the number of turbines necessary to generate that much energy.