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Fan Energy Savings Calculator

Calculate your potential energy savings with the fan energy savings tool.

Using actual fan specifications and flow rates will result in more accurate calculated energy costs.

Note: If the fan specifications are unknown, general assumptions can be made to give you an example of energy savings.

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Pressure Zero Flow

This value is used to generate a fan curve. The number must be > 100%. The greater the value, the steeper the fan curve is. The result of a higher number is greater power consumption with damper control.

Rated Flow

Enter the efficiency of the fan when operated at the rated flow rate.

5-30Hp typical 45-72%

40-150Hp typical 55-75%

200Hp & Up typical 75-90%

Minimum Flow

Enter the efficiency of the fan when operated at the minimum flow rate.

5-30Hp typical 25-55%

40-150Hp typical 30-60%

200Hp & Up typical 55-80%

Temperature

This value is used to calculate air density.

Altitude

This value is used to calculate air density.

Fan Rated Speed

The value entered for Motor Base Speed will be used as the Pump Rated Speed.

Rated Flow

This value should reflect the rated flow for the system. It is used to calculate HP requirements.
HP = CFM x PSF / 33,000 x efficiency

Minimum Flow

Enter the minimum flow rate for the system.

Pressure Rated Flow

The pressure is a resistance to flow and can be measured in several units. For this program convert all units to PSF.

Pressure Min Flow

Enter a value that is greater than "Pressure @ Rated Flow. This value is used to calculate Hp requirements.

Pressure Zero Flow

Value should be equal to or greater than the Pressure @ Minimum Flow. This value is used to draw the pump curve on the graph.

Rated Flow

Enter the efficiency of the pump when operated at the rated flow rate.

5-30Hp typical 45-72%

40-150Hp typical 55-75%

200Hp & Up typical 75-90%

Minimum Flow

Enter the efficiency of the pump when operated at the minimum flow rate.

5-30Hp typical 25-55%

40-150Hp typical 30-60%

200Hp & Up typical 55-80%

Rated Flow

Enter the value indicated on the graph for the specified flow.

Rated Flow

Enter the value indicated on the graph for the specified flow.

Motor Efficiencies
1800 RPM
Rated Hp
STD EDD.
% Eff
1329 OPD
% Eff
1329 TEFC
% Eff
1 74.4% 82.5% 82.5%
1.5 76.3% 84.0% 84.0%
2 77.8% 84.0% 84.0%
3 80.3% 86.5% 87.5%
5 83.6% 87.5% 87.5%
7.5 84.6% 88.5% 89.5%
10 85.9% 89.5% 89.5%
15 86.8% 91.0% 91.0%
20 88.8% 91.0% 91.0%
25 89.4% 91.7% 92.4%
30 90.0% 92.4% 92.4%
40 90.4% 93.0% 93.0%
50 91.3% 93.6% 93.0%
60 91.1% 93.6% 93.6%
75 91.3% 94.1% 94.1%
100 91.6% 94.1% 94.5%
125 91.6% 94.5% 94.5%
150 92.2% 95.0% 95.0%
200 93.5% 95.0% 95.0%
250 95.0% 95.4%
300 95.0% 95.4%
350 95.4%
400 95.8%
450
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600
700
800
1000
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Fan Energy Savings Calculator

INPUTS

Units

Load Sample Data
Minimum Flow %
% Pressure @ Zero Flow %

Efficiency

@ Rated Flow %
@ Minimum Flow %
Temperature °F
Altitude Ft
Annual Operating Time hours
Cost per kilowatt Hour cents

Motor

Rated Power
Base Speed RPM
Efficiency %


OUTPUTS



Summary
Control Method Annual US$
Damper $0.00
VFD Control $0.00
SAVINGS WITH VFD: $0.00

OUTPUTS



Summary
Control Method Annual US$
Damper $0.00
VFD Control $0.00
SAVINGS WITH VFD: $0.00


OUTPUTS



Summary
Control Method Annual US$
Damper $0.00
VFD Control $0.00
SAVINGS WITH VFD: $0.00