Cooling Tower Water Balance & Savings Calculator
Compare cooling tower operation at two cycles of concentration and estimate the change in make-up water, blowdown and annual water costs.
Water balance and cost comparison
Enter your evaporation loss and compare two operating scenarios. Proposed cycles are an assumption for comparison, not a chemistry-approved operating limit.
1. Your operating conditions
2. Your potential savings
Estimated annual cost saving
€84,000
Before additional treatment and investment costs.
24,000 m³/year
Make-up water reduction
20.0% less
24,000 m³/year
Blowdown reduction
60.0% less
| Current water and discharge cost | |
|---|---|
| Proposed water and discharge cost |
Check the proposed cycles against your water chemistry. Scaling, corrosion and biological control need separate assessment. This balance does not select a treatment programme or predict a safe maximum.
3. Current versus proposed
| Parameter | Current | Proposed | Reduction |
|---|---|---|---|
| Cycles of concentration | |||
| Make-up water (m³/h) | |||
| Blowdown (m³/h) | |||
| Annual make-up water (m³) | |||
| Annual blowdown (m³) | |||
| Annual make-up water cost (€) | |||
| Annual blowdown discharge cost (€) |
4. Proposed water balance
Make-up →
Cooling tower →
Steady-state balance
Water leaving
Make-up water replaces evaporation, blowdown, drift and other liquid losses.
Calculation method and assumptions
For steady-state operation, with evaporation containing negligible dissolved solids and other water losses at circulating-water concentration:
- Cycles, C = circulating-water dissolved-solids concentration / make-up concentration.
- Blowdown, B = E / (C - 1) - D - L.
- Make-up, M = E + B + D + L.
- Annual water and discharge cost = hours × (M × water tariff + B × discharge tariff).
E is evaporation, D is drift and L is other liquid loss, all in m³/h. Evaporation, drift, other losses and operating hours are held constant between the two scenarios. Cycles must exceed 1. A negative required blowdown indicates that the entered losses are inconsistent with the selected cycles; the calculator rejects that scenario.
Results assume constant operating conditions and tariffs. They exclude precipitation, chemical contributions to dissolved solids, treatment recovery losses, reuse loops, seasonal load changes, investment costs and treatment costs. Display rounding does not represent measurement accuracy.
Method background: U.S. Department of Energy: Cooling Tower Management.
Discuss your cooling-water savings potential
Contact Lenntech to discuss make-up water treatment and blowdown treatment options for your cooling system.