Calculation of hydroelectric power and energyhydroelectricity power calculator

Principle

The principle of hydro electricity generation is quite simple. Circuit waterworks provides the necessary pressure of water supplied to the turbine blades, which drives a generator, producing electricity.

Formula to calculate hydropower

How to calculate output power of a hydroelectric turbine? The simplest formula is :

formula hydroelectric power

Where
   P = Mechnical power in Watt (W)
   Q = flow rate in the pipe (m3/s)
   ρ = density (kg/m3)
   g = Acceleration of gravity (m/s²)
   H = waterfall height (m)
   η = global efficiency ratio (usually between 0,7 and 0,9)  




Calculator

Enter your own values in the white boxes, results are displayed in the green boxes.

HYDRO RESSOURCES

Flow rate : m3/s  l/s
Diameter of pipe :   cm
Section of pipe :   m²     Speed = m/s
Acceleration of gravity     m/s²
Waterfall height, head :   m
Density :   kg/m3 (usually 1000 kg/m3 for water)
Maximal power before losses : kW

LOSSES AND REAL ELECTRICAL POWER

Efficiency of turbine
Pressure drop factor
Other losses
Global Efficiency
Real electrical power (in kW) :     kW

ENERGY PRODUCTION AND FINANCIAL GAIN

Average number of working day per year :   days
Average annual energy in output of hydro generator :
    kWh/year
   MWh/year
Currency
Cost of energy :  /kWh
Total annual amount of electricity bill : /year

Example of stream flow in m3/s, l/minute and l/s, for hydro power calculation

Water stream Water flow in m3/s Water flow in l/minute Water flow in l/s
Tap water (pressure 2-3 bar) 0.0002 10 l/min 0.2 l/s
Fire hose 0.008 500l/min 8 l/s
Very small river < 2 m3/s < 120 000 l/min < 2 000 l/s
Small River > 2 m3/s > 120 000 l/min > 2 000 l/s
Big River 100 m3/s 6 000 000 l/min 100 000 l/s
Very big river >500 m3/s >30 000 000 l/min >500 000 l/s