The Life of Pumps

Pumping System Optimisation

ENERGY: - Pump Industry Facts

Pumps use a total of 20

TWh/annum in the UK

Produce 2.7 million tons of carbon

The largest user of motive power

in Industry

Pumps consume 20% of the

World’s electricity

70% of electric motor power is

used for pumps, fans, and

compressors

50% of pumping energy is wasted!

17.5

12.5

10 5

5

Pump Optimisation Pump Efficiency

Variable Speed / Trim Pipework Improvements

Correct Re-selection of Pumps

Why Pumps are expensive to operate?

Energy savings of 10% to 15% can be made by improving the efficiency of pumps.

Energy savings of 30% to 40% can be made by considering the performance of complete pumping systems.

Pump duties are often overstated at the design stage

Pumps are often throttled to meet operating conditions

Operational variations can lead to inefficient pumping regimes

Operating pumps inefficiently increases maintenance costs

Pumps wear in-service reducing their operating efficiency

Low efficiency pumps can still perform without any obvious problems

Pump Curve – Typical Losses

Actual

Output Q

H

Theoretical Output

Shock

Losses

Internal

Friction

Internal

Leakage

Pump Curve Interaction with System Characteristic

Efficiency Curve

Power Curve

Head / Flow Curve

System Resistance

Curve

Energy

Wastage

Energy Wastage

Energy

Wastage

Energy

Wastage

Energy Wastage

Energy

Wastage

Best Efficiency Point

“Sweet Spot”

Combined Characteristic of 4 Pumps Operating in Parallel

H

H2

H3

H4

1 Pump 2 Pumps 3 Pumps 4 Pumps

Q2 Q4 Q3 Q

Decreasing gain in head and flow with each additional pump

Head

Flow

System Curve Influence on VSD’s

1450 RPM 1350 RPM 1200 RPM 1100 RPM

Predominately Frictional System

System comprises mainly static

head with low frictional element

Best Efficiency

Point

Implications of Operating Away From BEP

The adverse effects of operating a pump away from peak efficiency

Head

Flow

High Temperature Rise

Low Flow Cavitation

Reduced Bearing/Seal Life

Reduced Impeller Life

Suction Recirculation

Discharge Recirculation

Best Efficiency Point

Cavitation from Lack of NPSH

Risk of Motor Overload

Pump Efficiency and Refurbishment

Pump Ownership Opportunities

Site performance testing

can identify opportunities

for pump upgrades and

finance subsequent

overhauls through energy

savings

Pump and System Audits

Pump Performance assessment

Pump Efficiency Improvements

System Curves

Data Logging

Pump Selection

Commissioning

Problem Solving

EU Law: Compulsory Energy Audits for large and medium businesses by 2015

Summary

Carry out pump audits:

Understand where your pumps operate in relation to BEP

Establish a hydraulic system resistance curve for all important

installations

Know how your pump is operating in relation to “as new condition”

Don’t automatically replace “like for like” without re-assessment

Make appropriate use of VSD’s, impeller trims and pump coatings

You can finance your pump maintenance and repairs through energy savings!

Thank you for Listening

Any Questions?