Which of the following is generally used for electricity generation?

The propeller rotor, a horizontal-axis design with a few aerofoil blades, is the type generally used to generate electricity from wind.

The Savonius rotor is a simple drag-based vertical machine suited to low-power uses, not large power output.

The Darrieus rotor is a vertical-axis lift machine used far less often for grid electricity.

The multiblade rotor with many blades is mainly used to pump water on farms.

The propeller rotor achieves high efficiency and captures energy well at typical wind speeds.

Modern wind turbines are large horizontal-axis propeller machines feeding power to the grid.