This document discusses opportunities for improving energy efficiency at the systems level for fluid handling systems. It notes that while component efficiency has improved, there are still significant savings potential through optimized variable speed operation, improved system design and integration. Specific opportunities mentioned include using more efficient motor designs integrated with flow devices, optimizing system sizing using tools to right-size pumps and motors, implementing variable speed control optimized for different operating conditions, and redesigning fluid devices like pulpers to reduce energy consumption by 30-50%. The EFEU program aims to develop these system-level efficiency improvements and estimates potential savings of 2-4% from more efficient pumps and motors and up to 30% from optimized speed control and system sizing.

1. Putting it all together:
Energy efficiency
opportunities at system
levels
31.10.2016
Tero Ahonen, LUT
EFEU WP coordinator:
Integrated energy efficient
systems

2. Motivation to systems-level research work
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EffectonsystemEs
Component efficiency η
• Fluid handling systems are notable contributor in global energy
consumption
• Energy saving potential decreases gradually with increasing
component efficiency, but huge savings still available through:
• Optimized variable-speed operation of fluid handling systems
• Improved system design, dimensioning and integration

3. Improvement potential in electric motors
• Modern electric motors provide easily ~90 % efficiency (IE3 class)
• Improvements and simultaneous cost savings possible through:
• Using of synchronous reluctance rotor; ~2 % units higher efficiency
with principally the same motor construction (IE4 eff. class)
• Motor design so that it is integrated to the flow device; less
bearings, possibility to fluid cooling→use of smaller motor size

4. Savings through optimized system selection
• Existing fluid handling systems are often overdimensioned for the
given application
• Pumping System Optimization Tool has been used to demonstrate
the savings potential available in a paper mill pumping system
• Installation of smaller&more efficient pump and motor
• Analysis of the resulting costs for the time period of 10 years has
shown in 20 % energy savings and payback time of ~3 years

5. Optimized variable-speed operation
• VSDs allows task execution with minimized energy consumption
• Optimum rotational speed is affected by the surrounding system,
which should be followed during the reservoir filling
• 31% savings in energy consumption, when constant speed of 1300
rpm is replaced with the optimized rotational speed profile
• Already finding the best constant speed provides ~30% savings
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Static head (m)
Rotationalspeed(rpm)
n with minimum E
s
Linear trendline
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Rotational speed (rpm)
Energyconsumption(Wh)
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Rotational speed (rpm)
Duration(s)
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6. Potential in optimized fluid device design
• Bale pulpers are used in paper mills to mix fiber pales with water
• Challenging to design, as the behavior of water-fiber fluids is not
yet well characterized
• Is it possible to redesign existing pulper rotor to reduce process
energy consumption even by 30%?
• New rotor design has decreased power consumption and especially
halved the mixing time, leading to ~50% energy savings

7. • EFEU program has resulted in
• ~2..4 % improvement in pump impeller and motor efficiency for
fluid handling systems, and with more to come through the benefits
of device integration
• Software tools to determine savings potential of 20 % by
optimized system dimensioning
• Speed control methods resulting e.g. 30 % energy savings
against the use of fixed-speed devices
• Flow device designs with halved energy consumption against
existing devices
Summary