Energy Management: Your questions answered

Webcast presenter Tom Wenning from Energy Efficiency Research & Analysis (EERA) answered additional questions about topics such as artificial demand, dilute/dense phase transport replacement, and why you shouldn't open manual drain valves.


Tom Wenning, program manager, Energy Efficiency Research & Analysis (EERA). Courtesy: Energy Efficiency Research & Analysis (EERA)The "Energy Management" webcast was presented live on May 3, 2018, by Tom Wenning, program manager, Energy Efficiency Research & Analysis (EERA). The webcast can be found here. He supplied written answers to some of those questions that weren't addressed from the webcast attendees:

Question: What should be the standard kwh consumption for full capacity running of centrifugal compressors?

Answer: A centrifugal compressor's operating efficiency is typically around 16 to 20 kW/100 cfm. I'd recommend visiting the Compressed Air and Gas Institute ( and checking out their compressor performance data sheets.

Q: What is artificial demand?

A: Artificial demand is defined as the excess volume of air that is consumed when supplying higher pressure than necessary for applications - unregulated and/or regulated to higher than necessary.

Q: What is a replacement for dilute/dense phase transport?

A: An alternative is a low- or high-pressure blower or a low pressure air compressor. You may want to take a look at the DOE's compressed air sourcebook: "Improving Compressed Air System Performance"

Q: Why should you not open manual drain valves?

A: There are four main methods for draining condensate from the system: manual valves, level-operated mechanical traps, electrically operated solenoid valves and zero air-loss traps. While manual valves can be effective, they may be very costly from an air-loss perspective. They should never be permanently "cracked open" to allow continuous condensate removal - this is extremely costly. The best solution from an energy/cost viewpoint is a zero air-loss trap.

Q: From your audits, do you have some examples of typical savings from energy recovery?

A: Heat recovery efficiencies can range a tremendous amount depending upon the equipment and end-use of the heat. The recovery can range anywhere from 50 to 90% of the available thermal energy, but again, it depends. I would recommend taking a look at the Heat Recovery factsheet in the DOE's compressed air sourcebook: "Improving Compressed Air System Performance

Q: What is the most common ECM that you have dealt with, with respect to compressed air systems?

A: The most common are reducing leaks, reducing system pressure, modifying/improving compressor control and eliminating inappropriate uses.

Top Plant
The Top Plant program honors outstanding manufacturing facilities in North America.
Product of the Year
The Product of the Year program recognizes products newly released in the manufacturing industries.
System Integrator of the Year
Each year, a panel of Control Engineering and Plant Engineering editors and industry expert judges select the System Integrator of the Year Award winners in three categories.
October 2018
Tools vs. sensors, functional safety, compressor rental, an operational network of maintenance and safety
September 2018
2018 Engineering Leaders under 40, Women in Engineering, Six ways to reduce waste in manufacturing, and Four robot implementation challenges.
GAMS preview, 2018 Mid-Year Report, EAM and Safety
October 2018
2018 Product of the Year; Subsurface data methodologies; Digital twins; Well lifecycle data
August 2018
SCADA standardization, capital expenditures, data-driven drilling and execution
June 2018
Machine learning, produced water benefits, programming cavity pumps
Spring 2018
Burners for heat-treating furnaces, CHP, dryers, gas humidification, and more
October 2018
Complex upgrades for system integrators; Process control safety and compliance
September 2018
Effective process analytics; Four reasons why LTE networks are not IIoT ready

Annual Salary Survey

After two years of economic concerns, manufacturing leaders once again have homed in on the single biggest issue facing their operations:

It's the workers—or more specifically, the lack of workers.

The 2017 Plant Engineering Salary Survey looks at not just what plant managers make, but what they think. As they look across their plants today, plant managers say they don’t have the operational depth to take on the new technologies and new challenges of global manufacturing.

Read more: 2017 Salary Survey

The Maintenance and Reliability Coach's blog
Maintenance and reliability tips and best practices from the maintenance and reliability coaches at Allied Reliability Group.
One Voice for Manufacturing
The One Voice for Manufacturing blog reports on federal public policy issues impacting the manufacturing sector. One Voice is a joint effort by the National Tooling and Machining...
The Maintenance and Reliability Professionals Blog
The Society for Maintenance and Reliability Professionals an organization devoted...
Machine Safety
Join this ongoing discussion of machine guarding topics, including solutions assessments, regulatory compliance, gap analysis...
Research Analyst Blog
IMS Research, recently acquired by IHS Inc., is a leading independent supplier of market research and consultancy to the global electronics industry.
Marshall on Maintenance
Maintenance is not optional in manufacturing. It’s a profit center, driving productivity and uptime while reducing overall repair costs.
Lachance on CMMS
The Lachance on CMMS blog is about current maintenance topics. Blogger Paul Lachance is president and chief technology officer for Smartware Group.
Material Handling
This digital report explains how everything from conveyors and robots to automatic picking systems and digital orders have evolved to keep pace with the speed of change in the supply chain.
Electrical Safety Update
This digital report explains how plant engineers need to take greater care when it comes to electrical safety incidents on the plant floor.
IIoT: Machines, Equipment, & Asset Management
Articles in this digital report highlight technologies that enable Industrial Internet of Things, IIoT-related products and strategies.
Randy Steele
Maintenance Manager; California Oils Corp.
Matthew J. Woo, PE, RCDD, LEED AP BD+C
Associate, Electrical Engineering; Wood Harbinger
Randy Oliver
Control Systems Engineer; Robert Bosch Corp.
Data Centers: Impacts of Climate and Cooling Technology
This course focuses on climate analysis, appropriateness of cooling system selection, and combining cooling systems.
Safety First: Arc Flash 101
This course will help identify and reveal electrical hazards and identify the solutions to implementing and maintaining a safe work environment.
Critical Power: Hospital Electrical Systems
This course explains how maintaining power and communication systems through emergency power-generation systems is critical.
Design of Safe and Reliable Hydraulic Systems for Subsea Applications
This eGuide explains how the operation of hydraulic systems for subsea applications requires the user to consider additional aspects because of the unique conditions that apply to the setting
click me