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How falling water drives a generator

More water, or a greater fall, means more power. Follow the water through a sectioned turbine, then follow its shaft up into the generator.

Reservoir → turbine → tailraceRunning · slowed motion

01 · Reservoir & penstockHead supplies pressure; the penstock carries water to the runner.

02 · Runner & shared shaftGuide vanes direct water onto the runner. Its torque turns the shaft.

03 · Generator & tailraceThe coupled rotor turns inside fixed coils. Water drains below.

Water flow · Q 2.0 m³/s

Net head · H 60 m

Electrical output

1,012.4 kW

Water flowing · generator coupled

P = ρ × g × Q × H × η

ρ = 1,000 kg/m³ · g = 9.81 m/s²
Fixed combined efficiency η = 0.86

1,177.2 kW hydraulic input · 14% losses

What this model explains. Gravitational potential becomes hydraulic energy, shaft work, then electricity. P is in watts when Q is in m³/s and H is in metres; the display converts W to kW. Net head is the available hydraulic head at the turbine. Efficiency is illustrative and held constant: real efficiency, friction, cavitation and operating limits vary. Cutaway geometry and motion are schematic, slowed and not to scale. Pausing freezes motion, not the power calculation.