Cleanroom Air Change Energy Cost Calculator
Connect ISO cleanroom airflow targets with the electrical load they impose. Enter room volume and ACH to reveal the airflow required, fan power draw, daily and annual energy consumption, and the annual electricity cost at your rate.
Confirm airflow and power calculations with your mechanical engineer of record before final design decisions.
Examples
- 18,000 cubic feet, 40 ACH, default fan intensity, $0.12/kWh, 24-hour operation ⇒ Required airflow: 12,000.00 CFM • Fan power draw: 7.80 kW • Annual energy consumption: 68,328.00 kWh • Annual energy cost: $8,199.36 • Daily energy use: 187.20 kWh per day
- 9,500 cubic feet, 20 ACH, 0.00055 kW/CFM, $0.16/kWh, 16-hour days ⇒ Required airflow: 3,166.67 CFM • Fan power draw: 1.74 kW • Annual energy consumption: 10,171.33 kWh • Annual energy cost: $1,627.41 • Daily energy use: 27.87 kWh per day
FAQ
Does this include reheat or cooling loads?
No. The calculator isolates fan energy. Add HVAC thermal loads separately for a complete utility forecast.
How do I handle variable air volume systems?
Use the highest ACH setpoint for a conservative design view, or average the CFM across control sequences to estimate typical energy use.
Can I model HEPA filter degradation?
Increase the fan power intensity to reflect higher static pressure as filters load, or rerun the numbers with end-of-life fan curves.
Additional Information
- Fan power intensity varies with filter loading, duct losses, and motor efficiency—adjust the optional input with commissioning data.
- Lowering ACH during unoccupied hours can yield significant savings; model shorter operating hours to quantify demand-based control strategies.
- Pair this calculation with chiller load estimates for a full HVAC energy profile.