NABCEP Wind Energy Site Assessment Flashcards
6 cards from real NABCEP practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 NABCEP Wind Energy Site Assessment flashcards as text
What is 'shadow flicker' in the context of wind turbine installations?
Answer: The alternating light and shadow caused by rotating turbine blades passing in front of the sun, affecting nearby residences
Shadow flicker occurs when rotating turbine blades periodically interrupt sunlight reaching nearby windows, creating a strobe-like effect that can be disturbing to occupants; most jurisdictions limit flicker to 30 hours/year.
What wind turbine component converts the kinetic energy of wind into rotational mechanical energy?
Answer: The rotor (hub and blades)
The rotor — consisting of the hub and blades — captures wind kinetic energy and converts it to shaft rotation, which is then converted to electrical energy by the generator.
What does 'capacity factor' mean for a wind turbine installation?
Answer: The ratio of actual annual energy produced to the theoretical maximum if the turbine ran at full rated power all year
Capacity factor compares actual output to the theoretical maximum, reflecting how well real-world wind conditions utilize the turbine's full capacity; US land-based wind typically achieves 25–45%.
What is the significance of the 'cut-in wind speed' of a wind turbine?
Answer: The minimum wind speed at which the turbine begins generating electricity
Cut-in wind speed is the minimum wind speed at which the rotor generates enough torque for the generator to produce useful electricity; below this speed the turbine is idle.
What type of permit is typically required before installing a small wind turbine in a residential zone?
Answer: A zoning or use permit, building permit, and utility interconnection agreement at minimum
Small wind installations typically require multiple permits: a zoning or special use permit for the structure's height and land use, a building permit for the foundation and tower, and a utility interconnection agreement for grid-tied systems.
What is 'wake effect' in a multi-turbine wind project and why does it affect siting?
Answer: The turbulence and reduced wind speed in the downwind shadow of an upstream turbine, reducing energy capture of turbines behind it
Upstream turbines extract energy from the wind and create a turbulent wake; turbines sited too close downwind operate in this reduced, turbulent flow and produce less energy with higher fatigue loads.