Small hydro constant-efficiency seasonal yield calculator

Calculate seasonal energy and unused water volume with your own figures.

Your numbers

Use the units shown. Results update as you change valid inputs.

Use seasonal energy and unused water volume to compare changes to your inputs. The method and limits below explain the scope.

Examples

Examples

Try the starting example

Available seasonal flows (m³/s)
0.2,0.5,0.8
Hours at each flow (hours)
2000,4000,2760
Minimum operating flow (m³/s)
0.1
Maximum turbine flow (m³/s)
0.6
Net head (m)
20
Constant overall efficiency
0.75
Seasonal energy (kWh)
596,636.586
Unused water volume (m³)
1,987,200
Used flow by season (JSON)
[0.2,0.5,0.6]

Try another scenario

Available seasonal flows (m³/s)
[1.2, 0.5, 0.8]
Hours at each flow (hours)
[2000, 4000, 2760]
Minimum operating flow (m³/s)
0.1
Maximum turbine flow (m³/s)
0.6
Net head (m)
20
Constant overall efficiency
0.75
Seasonal energy (kWh)
714,316.386
Unused water volume (m³)
6307200
Used flow by season (JSON)
[0.6,0.5,0.6]
Calculation method

Calculation method

Seasonal energy (kWh)

Apply supplied operating limits to flow-duration bins; integrate ρgQHη with constant efficiency and head.

Unused water volume (m³)

Apply supplied operating limits to flow-duration bins; integrate ρgQHη with constant efficiency and head.

Used flow by season (JSON)

Apply supplied operating limits to flow-duration bins; integrate ρgQHη with constant efficiency and head.

Symbols and units
a
Available seasonal flows (m³/s)
b
Hours at each flow (hours)
c
Minimum operating flow (m³/s)
d
Maximum turbine flow (m³/s)
e
Net head (m)
f
Constant overall efficiency

Use the units shown. A list keeps the order in which you enter its values. The symbol ^ means “raised to the power of”.

Assumptions & limits

Assumptions & limits

  • User-supplied measurements and assumptions; Apply supplied operating limits to flow-duration bins; integrate ρgQHη with constant efficiency and head. Supported limits: Finite numeric values bounded to 1e9 magnitude; lists and tables contain 1–100 records unless a stricter bound is stated. Inputs use the units shown. Lists explicitly paired by a method must have matching lengths; independent polynomial coefficient vectors may differ. Respect stated physical, interpolation, policy and computational domain limits.
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