has a minimum 30 m clearance between the bottom of the blades and the ground (or water);
pays back its cost in less than 10 years by selling electricity to the grid at $0.07 per kilowatt-hour (kWh); and
produces electricity at the minimum possible cost.
Which are the design criteria? Which are the design constraints? Write your answers in your report.
Simulation
In this interactive simulation, you will modify (and improve) an existing design for a wind turbine installation to produce electricity. You can vary the diameter of the turbine blades, the height of the tower holding the rotors, the number of turbines, and the wind speed for your location. Note that average wind speeds vary significantly not only across the United States but also within individual states.
Design and prototype
In the simulation it is assumed that you must purchase the land (urban, suburban, or rural sites) or lease it from the government (offshore, such as for the Cape Wind project off the Massachusetts coast); the costs will change depending on your siting choice. Use resources such as the maps at right to determine the typical wind speed for your potential sites.
Test
Investigate how the power produced and cost per kilowatt-hour vary with the design parameters (diameter, height, number of turbines, siting costs, average wind speed, and life expectancy). Identify the controlled variables in your investigation.
Evaluate
Evaluate your design to determine which solutions best meet the design criteria. Your design will pay back its cost over its lifetime when the cost per kilowatt-hour equals the average cost in your area. Research the average cost of electricity in your area (or state), which is usually provided in dollars per kilowatt-hour ($/kWh). A monthly home electricity bill is one way to determine the local cost of electricity.
Revise
How might you improve your design? Revise your design and evaluate it.
Design a wind turbine power plant
Design a wind turbine installation that 
