BOP Water Sizing Engine
Rigorous stoichiometric & cooling water calculations for commercial Green Hydrogen plants. Calculate Reverse Osmosis (RO) feed, evaporation loss, and pure water consumption.
System Parameters
Higher kWh/kg means more waste heat, increasing cooling water evaporation.
Water Mass Balance
Stoichiometric UPW Demand
0.00 L/hr
Math: H2 (kg) × 8.92 (Molar mass ratio of H2O to H2)
Cooling Evaporation Loss
0.00 L/hr
Math: Waste Heat (kW) × Latent heat of vaporization
Total Raw Water Intake (RO Feed)
0.00 L/hr
Math: (Stoic + Cooling) ÷ RO Recovery Rate
Reject Brine / Wastewater
0.00 L/hr
Math: Raw Intake – (Stoic + Cooling)
Engineering Standards & Citations
- Stoichiometric Demand (9.0 L/kg): Based on the molar mass ratio of H₂O (18.015 g/mol) to H₂ (2.016 g/mol) equating to 8.936 kg water per kg hydrogen. The 9.0 L/kg standard incorporates ~1% operational vapor loss (Ref: IRENA 2020, Green Hydrogen Cost Reduction, p. 54).
- Thermodynamic Baselines: Calculations assume a Lower Heating Value (LHV) for Hydrogen of 33.33 kWh/kg and an electrolysis thermoneutral voltage equivalent of 39.4 kWh/kg (HHV) (Ref: DOE Hydrogen and Fuel Cells Program Record, Table 2).
- Cooling Evaporation Loss: Waste heat is calculated as (Applied Specific Energy – LHV). Evaporation rates assume standard wet cooling towers rejecting latent heat of vaporization at approx 0.5 – 0.6 Liters per kWh thermal (Ref: ASHRAE Handbook – HVAC Systems and Equipment, Ch. 40 Cooling Towers).
- RO Recovery Rates: Assumes standard commercial Reverse Osmosis limitations: 75% for municipal low-TDS water, 60% for brackish groundwater, and 40% for seawater desalination systems (Ref: EPA Guidelines for Water Reuse, Section 4.3).