Electrolyser Calculator
Calculate required electrolyser size or hydrogen production by an electrolyser
Note:
The calculations provided by HyCalc are intended for preliminary estimates and scenario exploration. While we strive for accuracy, we recommend consulting qualified engineers for final system design, safety decisions, and regulatory compliance in your specific application.
How to Use This Calculator

Electrolyser schematics
Understanding Operation Modes
Production Mode
- Use when: You know your electrolyser's power capacity
- Calculates: Daily hydrogen production potential
- Typical users: Plant operators, energy planners
Example: A 5MW electrolyser @ 75% efficiency and 90% load factor produces
≈ 2,054 kg H2/day
Power Mode
- Use when: You have a target hydrogen production goal
- Calculates: Required electrolyser capacity
- Typical users: Project developers, system designers
Example: To produce 10,000 kg H2/day @ 80% efficiency and 85% load factor needs
≈ 24.2 MW capacity
Input Explanations
- Power/Hydrogen Production:
- Base parameter depending on selected operation mode
- Efficiency (%):
- System efficiency including power conversion losses (PEM: 70-85%, Alkaline: 60-75%)
- Load Factor (%):
- Annualized utilization rate (Grid-connected: 30-60%, Hybrid systems: 70-90%)
Key Considerations
- All values assume standard temperature (25°C) and pressure (1 atm)
- Assumes water density of 998 kg/m³
- Energy calculations based on higher heating value (HHV) of 39.44 kWh/kg