BUILDING TECHNOLOGIE

February 6, 2014 – revi

ASRAC Pumps Working Group

Metric Construct Details
2

Metric Applicability to Pump Configurations

Pump Configuration

Bare Pump Bare Pump + Motor Bare Pump + 

Metric Coverage

Bare Pump Does not include motor efficiency Does not d

losses 

Bare Pump +

Motor (w/ std. motor)

Does not d

losses 

Bare Pump +

Motor +

Controls (w/ std. motor and controls) (w/ std. controls)

Pump Motor

Pump Control M
3

Covered Product Metric

Bare Pump

Efficiency

or Energy

Use

Motor

Efficiency

or Energy

Use

‘Pump’

Efficiency or

Energy Use

=
4

Possible MetricPump Energy Rating (PER): equally weighted average electric inpu

(P1) to the ‘pump’ measured (or calculated) at the motor input or, 

present, controls input, over a specified load profile (100%, 75%, 5

25% of Best Efficiency Point (BEP) flow at nominal speed).

• For bare pump or pump+motor, a

part‐load by throttling through p

at rated speed.

• For pump+motor+controls, achie

load by reducing speed and corre

specified system curve shape.

PER = 0.25(P1BEP) + 0.25(P11.1BEP) + 0.25(P10.75 BEP) + 0.25(

Notes:Denominator could be included in metric

Rating point of 25% may not be appropriate/feasible for throttled configurations
5

PER Options

No Denominator Denominator

Form Weighted average of

pump input power at

several load points

Weighted input of pump in

several load points normal

hydraulic output power, a 

pump efficiency, or other v

Units kW, Btu, or HP Dimensionless*

Standard Strong function of flow

and specific speed

Weak function of flow and 

speed

Pros Representative of the

energy consumption ofthat pump in the field

More comparable across p

different sizes/specific spe

Similar to EEI approach in 

Cons Not comparable across

pumps of different

flows/specific speeds

No reference pump efficie

difficult to set; other deno

options may not be logical 

next slide)

*May vary based on denominator chosen
6

Denominator Options

Denominator Pros ConsPower consumptionof same pump in an

uncontrolled system

N/A

This value give

efficiency of thwith equivalen

performance a

efficiencies at 

same rated val

Reference shaft

power for minimally

compliant bare pump

with minimallycompliant motor

Results in value between 0

and 1.Clearly indicates performanceof a pump relative to a

baseline.

Inherently req

minimally com

MEI). May ovethe baseline ef

pumps.

Market average shaftpower with

minimally compliant

or market averagemotor

Indicates performance of a

pump relative to the market.

Locks in the m

performance omarket at a giv

Doesn’t limit m0 and 1.

Tested pump’s

hydraulic power at

BEP

Accounts for differences inpump efficiencies betweenmodels.Has similar rated values for

pumps of different sizes

Lower PER rati

because lower 

is inherently le
7

×

standardized motor

efficiency and part load

curve

MOTOR

pump performan

from pump test 

speed

Bare Pump Testing

×

standardized controls

performance

Controls

Example of Motor Choice:

• If standard motor: AC Induction, NEMA Design B, open enclosure.

• Could use next HP above brake horsepower at 120% BEP or 

defined motor rating.

• Poles would be based on speed at which pump is being rate

• If standard full load motor efficiency is used, it would be based on 

standards (assuming the motor is a type covered by Federal stand

• Could use full load motor efficiency for all points or develop stand

part‐load curves.
8

×

manufacturer motor

efficiency at full and part

load

A MOTORB MOTOR PUMP

Bare Pump + Motor Testing

Ma

pai

with 

Ma

me

p

standardized controls

performance

Controls ×

pump performance

data from pump

test at rated speed

standardized controls

performance

Controls ×
9

pump performance from pump test at

rated and reduced speed

×

motor/drive performance

data

BC

VFD MOTOR

Controls MOTOR PUMP

Bare Pump + Motor + Controls Testing

Ma

pai

mo

Ma

me

p

co

×

manufacturer or default

motor efficiency

A MOTOR

Ma

pai

with 

m

de

pump performance

data from pump test

at rated speed

default controls

performance

Controls ×
10

Bare Pump/Bare Pump + Motor Equation
11

Bare Pump + Motor + Controls Equation
12

Issues to Discuss
13

Example of Metric Application

Note: The example on the following slides is provided for the lim

purpose of demonstrating the potential application of the PER m

does not represent a decision by DOE on an appropriate metric o

level for the products to be addressed by the pumps working gro

 Values used to compare an example pump to the example calculated 

level are for illustration purposes only and should not be considered 

representing recommended values.

 The comparison of the example PER metric to the MEI metric is prov

demonstrate the results of the calculation, and does not represent a

by DOE of the relative merits of one approach over the other.
14



How efficiency levels could be set
15

 ݑ݌ߟ݉݌, BEP can be calculated the same way as in MEI, as a function of flow a

speed.

 ݑ݌ߟ݉݌ at 75%, 50%, and 25% can be calculated as a percentage of 

ߟ

• In the EU, pump efficiency at 75% BEP flow must be 94.7% of ݑ݌ߟ݉݌, B• In the EU, pump efficiency at 75% BEP flow must be 94.7% of ݑ݌ߟ݉݌, B• Using a subset of HI data (ESFM pump, 4 pole*), DOE analyzed part‐lo

efficiency as a percentage of BEP efficiency:

• The results, in the form of population average values, are as follows:

- At 75% BEP flow, ݑ݌ߟ݉݌,0.75 is 95% of ݑ݌ߟ݉݌, BEP

– Efficiency as a percent of ݑ݌ߟ݉݌, BEP was independent of flow and fairly indepe

speed

– Agrees with EU value

- At 50% BEP flow, ݑ݌ߟ݉݌,0.50 is 78.5% of ݑ݌ߟ݉݌, BEP

– Estimated ݑ݌ߟ݉݌, 0.50 by fitting 2nd order polynomials to the 75%, 100%, and 11

data provided by HI.

– Efficiency as a percent of ݑ݌ߟ݉݌, BEP was independent of flow, fairly independe

speed, but showed a larger standard deviation than at 75% BEP (possibly due 

(data 0.50 ,݌݉

- 25% BEP flow: No data available; this flow point is omitted for this analys

*All equipment classes will be analyzed in the futureSetting Target Values
16

How efficiency levels could be set: Bare PumpsWith ݑ݌ߟ݉݌, 0.50 and ݑ݌ߟ݉݌, 0.75 defined as (0.785 x ݑ݌ߟ݉݌, BEP) and (0.950 x 

ߟ

respectively, and using full load motor efficiency for all points, the PEREff.

equation can be simplified to:ܲܧܴா௙௙.௅௘௩௘௟ ൌ 	

1

௥௢௧௠௢ߟ

ൈ ߱଴.ହ଴

ܲ௛௬ௗ௥௔௨௟௜௖,଴.ହ଴

0.785	 ൈ 	ߟ௣௨௠௣,஻ா௉

+߱଴.଻ହ

ܲ௛௬ௗ௥௔௨௟௜௖,଴.଻ହ

0.950 ൈ 	ߟ௣௨௠௣,஻ா௉

+߱୆୉୔

ܲ௛௬ௗ௥௔௨௟௜௖,

ߟ௣௨௠௣,஻ா

Where:

ݑ݌ߟ݉݌, BEP in this example is from the MEI surface, using flow and specific s

• If this approach is used, the actual value of ݑ݌ߟ݉݌, BEP could be determined by the C‐v

Level” that is ultimately selected as a result of the standards analysis.

Please Note: the values of 0.785 and 0.950 are preliminary and are used for demo

purposes only. If this approach is used for the rating metric and standard, the sele

actual values for these factors would be made based upon further analysis.
17

Example Scenario and CalculationsGiven the Following Theoretical Pump and Parameters• BEP Flow: 880 GPM

• BEP Head: 117 ft

• Specific Speed: 1500

• PBEP = 30.99 HP (Shaft), 26.0 HP (Hydro)

• P0.75 = 27.67 HP (Shaft), 22.4 HP (Hydro)

• P0.50 = 24.64 HP (Shaft), 17.6 HP (Hydro)

• ߟMotor, Default = 93%

• Load Point Weight = 1/3 [even]

ܲܧܴ௖௟௔஼௨௟௔௧௘ௗ ൌ	߱଴.ହ଴

ܲ଴.ହ଴

௥௢௧௠௢ߟ

൅ ߱଴.଻ହ

ܲ଴.଻ହ

௥௢௧௠௢ߟ

൅ ߱஻ா௉

ܲ஻ா௉

௥௢௧௠௢ߟ

ܲܧܴ௖௟௔஼௨௟௔௧௘ௗ ൌ 	

1

0.93 ൈ

1

	ܲܪ	29.86 ൌ ܲܪ30.99 ൅ ܲܪ27.67	 ൅ ܲܪ24.64 ൈ 3

84.04% = BEP ߟ

80.98% = 0.75 ߟ

71.50% = 0.50 ߟ
18

Example Scenario and Calculations

PERCalculated: 29.23

ߟ pump, BEP = 84.04%

Passing C‐Value for this Pump: 122.21

MEI Level C‐Value [EU Lot 11] ߟPump, BEP PEREff. Level

10 132.58 75.33% 33.6040 128.07 79.84% 31.7070 124.85 83.06% 30.4780 122.94 84.97% 29.79

These results demoncalculated PER for th

pump would comparexample PER efficieneach MEI cutoff levewith the C‐value cuto

the same pump.
19

Setting Efficiency Levels• PER = Controls Motor Bare Pump

Default

= 1?

Default MEI 10

MEI 20...MEI 70