Winter 2005

ISSUE FOCUS:

Unbalanced Voltage

“ T U R N I N G I N F O R M A T I O N I N T O E N E R G Y S O L U T I O N S F O R I N D U S T R Y ”

I N D U S T R I A L T E C H N O L O G I E S P R O G R A M

IN THIS ISSUE

Stopping a Costly Leak: The Effects 

of Unbalanced Voltage on the Life 

and Efficiency of Three-Phase 

Electric Motors . . . . . . . . . . . . . 1

Compressed Air System 

Improvement Project Yields 

Substantial Energy Savings at a 

Paper Mill . . . . . . . . . . . . . . . . . 3

Mill Identifi es Energy and Operational 

Improvements that May Save $9.6 

Million Annually . . . . . . . . . . . . . 3

Energy Matters wants you to go 

electronic . . . . . . . . . . . . . . . . . 5

Berkeley Lab Finds Industrial Energy 

Efficiency Strategies Can Help Ease 

Natural Gas Prices . . . . . . . . . . . 7

Watch for Fan System Qualified 

Specialist Training Opportunities . 7

Coming Events . . . . . . . . . . . . . 8

Unbalanced voltage damages 

motor. (page 1)

Stopping a Costly Leak: The Effects of Unbalanced 

Voltage on the Life and Effi ciency of Three-Phase 

Electric Motors

Energy Matters

By Chuck Yung, EASA

Editor’s Note: This is the first of a two

part series considering some of the energy 

efficiency issues related to power quality. The 

Spring issue continues this discussion with 

an article from the Electric Power Research 

Institute. 

Electrical power quality problems cost U.S. 

industry $40-150 billion each year, according 

to some estimates. Most problems originate 

outside our plant and are therefore beyond 

our control–for example, outages, voltage 

interruptions, voltage sag, voltage reductions, 

and blackouts. Others may be traceable either 

to the utility grid, plant conditions, or some 

combination of the two. 

The good news is that we can do something about one of the most pervasive (and 

insidious) power quality problems–voltage 

unbalance. The bad news is that this problem is easy (and costly) to overlook. At the 

very least, voltage unbalance reduces motor 

efficiency, potentially robbing you of the savings you expected to realize by upgrading to 

EPACT or National Electrical Manufacturers 

Association (NEMA) PremiumTM efficiency 

motors. More serious consequences include 

premature motor failure, costly shutdowns, 

and lost production. 

What is unbalanced voltage, and where 

does it come from?

Voltage unbalance describes the condition 

when the voltages of all phases of a 3-phase 

power supply are not equal. You might expect 

the electricity used by your 3-phase electric 

motors to be balanced, but it rarely is. According to ANSI C84.1 -1995, Electrical Power 

Systems and Equipment – Voltage Ratings 

(60Hz), only 66% of the 3-phase power delivered to industrial plants is within 1% voltage 

unbalance. In addition, 98% of all voltage 

generated by electric utilities has 3% or less 

unbalance. Only 2% of the voltage produced 

by the electric utilities has a voltage unbalance greater than 3%. 

The underlying causes of voltage unbalance are numerous, and may include:

• Lack of symmetry in transmission lines

• Large single-phase loads (for example, arc

furnaces, welders, and so on)

• Faulty power factor correction capacitor 

banks

• Open delta or wye transformers.

 Plant conditions that can cause or contribute to voltage unbalance include unbalanced 

or overloaded transformers, malfunctioning 

power factor correction devices, cyclical controls, and detuned reactors. Even what’s happening at the plant next door or farther up the 

power line could affect the voltage unbalance 

at your facility. One plant reported 8% voltage unbalance; the cause was an aluminum 

plant next door, with predominantly singlephase furnace loads.

The bottom line: if your plant uses 3-phase 

power and you haven’t taken corrective measures already, there’s a fairly good chance you 

have unbalanced voltage. 

How to tell

To find out if your plant has a problem 

with voltage unbalance, measure the line voltages of your 3-phase power supply where it 

enters the plant and then again at several critical locations within the plant under normal 

operating conditions. Use those measurements 

to solve the following equation:

For example, if measured line voltages 

were 455, 460, and 492, the average would be 

469 volts (455 + 460 + 492 = 1407 / 3 = 469). 

The maximum deviation from that average is 

23 volts (492 - 469 = 23). To find the voltage 

unbalance, solve the equation for the average 

voltage and the maximum voltage deviation:

(continued on page 2) 

Voltage unbalance =

100 x Max. deviation

from average voltage

Average voltage

Voltage unbalance = 100 x (23/469) = 4.9%
2 Energy	Matters,	Winter	2005 

Why you should care

The most apparent effects of voltage 

unbalance are decreased motor efficiency 

and performance–both of which affect your 

company’s profitability.

Any given motor’s efficiency will vary, 

depending upon such factors as the type of 

application, the load, and the supply voltage. 

In fact, even the efficiency ratings of the new 

NEMA Premium motors are possible only if 

they operate on balanced voltage. 

That’s because motors built to comply 

with the NEMA standard MG 1 are designed 

to operate on voltage balanced to within 1%. 

Operating on a power supply with a larger 

voltage unbalance will increase the I2R losses 

(that is, current squared times resistance) in 

the rotor and stator, meaning more of the supplied power will be converted to heat and less 

to work. The motor therefore will run hotter 

and, consequently, less efficiently. Increased 

rotor losses also will increase “slip,” so the 

motor will turn a little more slowly and do 

less work in a given time.

The following table shows how unbalanced voltage affects the temperature rise, 

losses, efficiency, and life expectancy of a 

typical 3-phase motor operating at rated load.

Operating on unbalanced voltage also 

causes the rotor’s temperature (heat = losses) 

to rise. That adversely affects its performance 

causing it to rotate slower and leading to an 

increase in its “slip”. Slip can be calculated 

by:

To get a better grasp of how unbalanced 

voltage affects motor performance, consider 

the most common industrial application for 

electric motors–pumps. Take a 4-pole, 60 

Hertz (Hz) pump motor with a synchronous 

speed of 1,800 revolutions per minute (rpm) 

that operates at 1,764 rpm at the correct balanced voltage. The slip for this motor would 

be: 

With 3% unbalanced voltage, slip would 

double, reducing the speed to about 1,728 

rpm: (1.0 - .04) x 1800 = 1728

Since the volume of product being 

pumped varies in proportion to the speed, not 

only would the motor be 2% to 3% less efficient (referring to the table) when operating 

from unbalanced voltage, but it also would 

have to run 3% longer to do the same amount 

of work. The savings by correcting the unbalanced voltage will roughly equal the sum of 

the increased losses (reduced efficiency) and 

the longer run time required.

Unbalanced voltage shortens motor life

Another cost of operating on unbalanced 

voltage is reduced motor life. Recall that 

operating with a voltage unbalance greater 

than 1% will increase the I2R losses in the 

rotor and stator, causing the motor to run hotter. In fact, the temperature of the windings 

(in degrees Celsius) will increase by twice the 

percent of voltage unbalance squared. 

Since every 10o C increase in temperature 

cuts the insulation life in half, a 3% voltage 

unbalance could reduce the life of the winding to about one-fourth its expected life. A 5% 

voltage unbalance could reduce winding life 

to less than the typical warranty period for a 

new motor (2 x (5) 2 = 50o C). The accompanying figure illustrates this point.

Energy Matters

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Energy Matters newsletter) and 

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■

Editorial Board

Tom Bishop

Electrical Apparatus Service 

Association

Rob Boteler, representing National Electrical Manufacturers 

Association

Eric T. Fletty, Business 

Development Manager, TAPPI

Gary L. Goehring, Alcoa 

North American Extrusions

Glenn Hahn, Spirax Sarco

J. Bruce Medaris, Facilities 

Consulting Services and 

Executive Director, Compressed Air 

Challenge®

Michael R. Muller, Center for Advanced 

Energy Systems, 

Rutgers University

Arvind Thekdi, E3M, Inc.

Chuck Whelan, DuPont 

■

DOE Staff

Chris Cockrill, BestPractices, Motors

Bob Gemmer, Process Heating and 

Steam

Grace Ordaz,

Technology Manager

Peter Salmon-Cox, Lead 

Technology Manager, Technology 

Delivery and BestPractices 

■

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Stopping a Costly Leak: The Effects of Unbalanced Voltage on the Life and Efficiency of 

Three-Phase Electric Motors (continued from page1)

% voltage 

unbalance

Winding temp. 

(° C)

I

2R losses (% of 

total)

Effi ciency 

reduction

Expected winding life (years)

0 120 30% – 20 years

1 130 33% Up to 1/2% 10

2 140 35% 1 - 2% 5

3 150 38% 2 - 3% 2.5

4 160 40% 3 - 4% 1.25

5 180 45% 5% or more Less than 1

The windings in this motor were damaged by 

operation on unbalanced voltage.

% Slip = 

(Synchronous rpm - actual rpm)

synchronous speed [ ] x 100

= 2% Slip (1800 - 1764)

1800 

x 100 [ ]

 = .980 or 98.0% 1728

1764 Pump flow =

2 x (3)2 = 18o C
Energy	Matters,	Winter	2005 3

(continued on page 4) 

Factor in replacement or repair costs for 

premature motor failures, unscheduled downtime, and lost production, and the true cost of 

unbalanced voltage can be much higher than 

the cost of the wasted electricity–possibly as 

high as a factor of 10. The table below shows 

the cost of downtime for some representative 

industries.

How can we correct it?

The first step in correcting the problem 

is to measure the voltage unbalance in your 

plant. Especially if the unbalance exceeds the 

utilities’ standard of 3%, make your utility 

aware of it. 

Next, measure the line voltages at several 

key locations in your plant to identify conditions that cause or contribute to unbalanced 

voltage. A number of products are available 

to help you correct the problem. At one end 

of the spectrum are basic reactors with adjustable taps on each phase. With these units, you 

can regularly monitor the voltage balance 

and make any needed corrections by changing taps. At the other end of the spectrum are 

sophisticated, computer-controlled devices 

that monitor and automatically correct voltage 

and power factor problems. 

Industries vary in their use of 3-phase 

motors. The higher your electric motor usage, 

the greater the impact unbalanced voltage 

will have on electric bills. Additionally, if a 

neighboring plant creates an unbalanced voltage situation, your plant also may experience 

considerably higher costs related to unbalanced voltage.

Summing up

The cost of unbalanced voltage to U.S. 

industry may be as much as $28 billion a 

year. The savings are even more substantial 

when you consider the value of “uptime” and 

extended equipment life. Like a leaky faucet, 

even a small drip can waste hundreds of gallons daily. With voltage unbalance, though, 

it’s not just water but your money that is 

going down the drain!

Chuck Yung is a technical support specialist at the Electrical Apparatus Service Association (EASA), St. Louis, MO; 314-993-2220; 

314-993-1269 (fax); www.easa.com. EASA 

is an international trade association of more 

than 2,150 firms in 50 countries that sell and 

service electrical, electronic, and mechanical 

apparatus.

Compressed Air System 

Improvement Project 

Yields Substantial Energy 

Savings at a Paper Mill

In 2002, employees at Procter & Gamble’s 

(P&G) paper products mill in Mehoopany, 

Pennsylvania performed a project that 

improved the efficiency of the mill’s compressed air system. The project was based on 

recommendations from DOE Allied Partner, 

Air Science Engineering, and it included the 

installation and configuration of a sophisticated network controls package with Management Information System (MIS) capability, 

the addition of system piping, and the installation of a 1,500 hp compressor to satisfy an 

anticipated increase in production. Once the 

project was completed, the plant was able 

to take a 450 hp compressor offline and still 

maintain the minimum pressure level required 

to adequately supply its end-use applications. 

The project saved 7,600,000 kilowatt-hours 

(kWh) and $304,000 per year in compressed 

air energy costs and $5,000 in annual maintenance costs for a total of $309,000. With a 

total project cost of $545,000, the simple payback was 1.75 years. 

Proper compressor control is essential for 

efficient compressed air system operation 

and peak performance. At P&G’s Mehoopany paper products mill, compressors are 

located in different buildings across the facility. Before the project, plant personnel had 

to operate all the units because they could 

not determine when to shut off unneeded 

compressors or when to delay bringing additional ones online. This configuration made it 

logical for the Mehoopany mill to acquire a 

sophisticated compressor control system that 

could effectively orchestrate the operation of 

multiple compressors that are spread apart 

in various locations. The installation of these 

controls was executed within the context of 

a system-level strategy to improve system 

performance. Once the additional action items 

were implemented, the system was able to 

match its air supply to its air demand more 

closely, which led to more efficient compressor operation and considerable energy savings. 

Moreover, the control system was able to 

stabilize the pressure level, thereby avoiding 

the purchase of additional capital equipment. 

This project and its results are being shared 

with other P&G sites with similar compressed 

air systems.

Mill Identifies Energy and 

Operational Improvements that May Save $9.6 

Million Annually

In partnership with the Industrial Technologies Program (ITP), Georgia Pacific (GP) 

completed a plant-wide assessment (PWA) at 

its Crossett, AR, facility in 2002 and identified $9.6 million in potential annual savings. 

The plant thus far has implemented about 

30% of the projects identified in the PWA 

and has captured annual savings of $3.9 million related to energy reductions. During the 

course of implementing the PWA projects, 

other savings opportunities came to light and 

are being considered for implementation. In 

addition, four other GP plants in the South 

have replicated some of the projects first identified by the Crossett PWA.

An assessment team conducted a mill-wide 

energy survey at Georgia-Pacific’s Crossett, 

AR, mill as an update to a previous pinch 

analysis. Pinch analysis provides a systematic 

approach for analyzing energy networks to 

improve the energy performance of industrial 

60 80 100 120 140 160 180 200 220 240

1,000

10,000

100,000

1,000,000

10

Average expected life in hours

Total winding temperature (°C)

Class A

Class B

Class F

Class H

Temperature vs. Life Curves for Insulation Systems*

*Per IEEE 117-1996 and 275-1992

Industry Cost of downtime,

$ / hour

Pulp & Paper 15,000

Petro-chemical 150,000

Computer manufacturing$4 million per incident

Cost of downtime for various industrial segments.

Figure 1. For every 10° C increase in winding temperature, insulation life is cut in half.
4 Energy	Matters,	Winter	2005 

processes. It uses graphical representations 

of the energy flows in the process and utility 

streams to determine the minimum energy 

consumption that a process should use to meet 

its specific production requirements.

The team wanted to identify energy conservation measures and operating practice 

improvements that would increase the mill’s 

overall energy efficiency. Three heat recovery 

projects were identified that could reduce 

annual costs by about $4.8 million and annual 

natural gas use by 1,845,000 million British 

thermal units (MMBtu). The overall payback 

period for the heat recovery projects would 

be less than 1 year. The team also addressed 

operational improvements during the assessment. Implementation of operations improvements could yield an additional $4.8 million 

in annual savings, along with 1,500,000 

MMBtu in natural gas savings.

ITP cosponsored the assessment through 

a competitive process. DOE promotes 

plant-wide energy-efficiency assessments 

that will lead to improvements in industrial 

energy efficiency, productivity, and global 

competitiveness, while reducing waste and 

environmental emissions. In this case, DOE 

contributed $100,000 of the total $290,000 

assessment cost.

Founded in 1927 as a wholesaler of hardwood lumber, Georgia-Pacific Corporation 

has become one of the world’s leading manufacturers and distributes of packaging, paper, 

building products, pulp, and related chemicals. 

Georgia-Pacific is a worldwide company with 

approximately $30 billion in sales, employing 

85,000 people in more than 600 North American locations and in 11 European locations.

Georgia-Pacific Corporation purchased 

the Cross Lumber Companies in 1962, spending more than $124 million for operations 

and land holdings in southeast Arkansas. 

The first paper machines were installed in 

Georgia-Pacific Cross Paper Operations in 

1937. Georgia-Pacific employs 2,700 people 

in the Crossett area, while Crossett Paper 

Operations employs 1,650 people. The plant 

produces more than 650,000 tons of printing 

paper, board, and tissue products each year. 

The mill generates 75% of its own power and 

also has its own treatment system for both 

incoming and outgoing water. The Crossett 

complex consists of the paper mill, plywood 

mill, and chemical plant.

The Crossett mill cooks wood chips in two 

parallel batch digester lines to produce hardwood and softwood pulp. Each pulp production line includes its own washing plant. Two 

parallel bleach plants complete the hardwood 

bleaching; the softwood bleaching is done in 

a single line. The bleached pulp is mixed prior 

to entering the paper machines as required 

for each grade. The mill consists of two paper 

machines that make lightweight paper such 

as those used in copy machines, one board 

machine that makes paper used in lightweight 

boxes, and five tissue-paper machines.

The pulping liquor is processed through an 

integrated pre-evaporator and stripper system, 

followed by an evaporator train, concentrators, 

and super concentrators. The concentrated 

black liquor is fed to the single recovery 

boiler, then to a recausticizing system that 

produces white liquor for the pulping process. 

Steam from the recovery boiler is supplemented by steam produced in the power boilers. Two power boilers primarily use wood 

waste as fuel. Two natural gas-fired boilers 

back up the power boilers. Three backpressure turbines generate the majority of the mill 

power and supply process steam.

Assessment Approach

The assessment team performed a plantwide energy assessment as an update to an 

earlier pinch study. The assessment’s primary 

objective was to define energy conservation measures and to recommend operating 

practice improvements to increase the mill’s 

overall energy efficiency. Elements of the 

assessment included:

• Formulating heat and material balances

• Modeling the mill’s energy profile and 

constraints affecting the profile

• Evaluating the efficiency of generation, 

purchase, and use of energy

• Characterizing the minimum thermal 

energy requirement for operation

• Formulating heat recovery projects that 

could reduce the mill’s total thermal 

energy consumption

• Targeting cogeneration analysis.

The assessment team applied pinch technology and the Showcasing True Energy 

Potential (S.T.E.PTM) methodology developed 

by American Process Inc. (API) to examine 

electrical and thermal energy usage, generation, and purchasing. 

Georgia Pacific’s assessment team used 

the S.T.E.P. methodology to evaluate the 

efficiency of in-house steam generation and 

production processes, and to review the mill’s 

energy purchasing policies. For example, 

the team identified maximum sustainable 

capacities and production bottlenecks. Data 

representing seasonal fuel use and steam production were used to create an energy profile. 

Use of alternative fuels was explored. The 

team also conducted walk-downs to identify 

potential cost and energy savings through 

improvements in housekeeping (for example, 

repairing leaks in the steam delivery and compressed air systems; insulation upgrades). The 

team then made a series of recommendations 

for operational improvements and low- or noncapital projects that the mill will continue to 

evaluate for potential implementation.

The energy efficiency study focused on 

reducing the amount of fuel used to make 

steam. Overall, the team examined equipment and departmental efficiencies, electrical 

and thermal benchmarking, housekeeping, 

process modifications, cogeneration, and process controls in a systematic and integrated 

approach.

If Georgia-Pacific implemented three 

proposed heat recovery projects at the Crossett mill, it would reduce natural gas use yearround and reduce purchased wood waste in 

the summer. Furthermore, during the winter, 

two power boilers would only operate at a 

minimum capacity to respond to fluctuations in steam demand. Implementing these 

projects would yield an annual cost reduction 

of about $4.8 million and annual natural gas 

savings of 1,854,000 MMBtu. The overall 

payback period would be less than 1 year.

Projects involving operational improvements and cogeneration were also addressed 

during the S.T.E.P study. Operational changes 

could save an additional $4.8 million annually 

if natural gas use were reduced. These S.T.E.P 

projects’ savings are more subjective than 

those from the heat recovery projects. Benchmarking targets and detailed assessments are 

required before project implementation. Savings and capital costs depend on operational 

and maintenance policies, and were not calculated as part of the assessment.

Additional cogeneration is not currently 

considered to be economically attractive, 

and implementing the heat recovery projects 

would reduce the opportunities for cogeneration.

The table summarizes the heat recovery 

and operational improvement projects identified during the assessment.

Project 1: Heat Recovery from Bleach 

Plant D Effluents

In the current mill configuration, effluents 

from the bleach plant D-stage washers are 

directed to the sewer. The effluent streams 

Mill Identifies Energy and Operational Improvements that May Save $9.6 Million Annually (continued from page 3)

(continued on page 6) 
Energy	Matters,	Winter	2005 5

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6 Energy	Matters,	Winter	2005 

contain a large amount of heat that is being 

wasted. This project proposes to install a 

new heat exchanger to capture this heat and 

generate warm water for the paper machines. 

Using this warm water on the machines will 

reduce the amount of steam required to heat 

the white water.

Project 2: Improved Blow Heat Recovery 

and Demineralized Water Heating

The blow heat recovery system captures 

the heat from the flash steam generated when 

a digester is emptied from approximately 100 

pounds per square inch gauge (PSIG) to an 

atmospheric storage tank. The flash steam 

is condensed, and an accumulator stores 

the condensate. From the accumulator, the 

condensate is routed through a series of heat 

exchangers, where it is cooled and returned to 

the bottom of the accumulator. With the current configuration, a cooling tower removes 

excess heat from the accumulator and a steam 

heater generates hot water for the bleach plant. 

This project’s purpose is to improve the heat 

recovery in the blow-heat area of the pulp 

mill and E-stage bleaching effluent for demineralized water heating. By installing new heat 

exchangers and rerouting some water lines, 

the cooling tower can be shut down and the 

steam heater removed. Steam reduction would 

lead to cost savings.

Project 3: Bleach Plant Prechiller

The mill continuously operates two chillers to provide cold water for the chlorine 

dioxide (ClO2) plant. The chillers take well 

water that is a constant 70°F all year and chill 

it to around 45°F. The proposed prechiller 

would utilize 50°F ClO2 solution from the 

ClO2 plant to cool the incoming well water. 

This will not only reduce electrical energy 

demand from the chillers, but will also preheat the ClO2 solution going to the bleach 

plant and reduce the amount of steam needed 

for heating.

The assessment team also addressed operational improvements and cogeneration opportunities. The mill would save on operating 

costs by improving mill operational parameters, housekeeping, and purchasing strategies. 

Cogeneration opportunities include those 

resulting from noncapital operational changes 

and a possible turbine upgrade. Because they 

are currently considered to be economically 

infeasible, the team did not estimate capital 

costs for cogeneration projects. Implementing all the heat recovery projects would also 

decrease the opportunities for cogeneration 

capacity. Implementing all heat recovery projects and operational improvements together 

may not be feasible and may require additional expenditures and analysis.

Operational Improvements

The assessment team studied various 

operational improvements to increase energy 

efficiency and energy conservation. The quantified items included improved boiler oxygen 

control, tank insulation, condensate recovery, 

steam and compressed air leak repair, and 

a more efficient black liquor evaporation 

scheme.

Process changes include increasing the 

high-pressure steam header pressure and 

reducing low- and medium-pressure header 

pressures. The savings would be obtained by 

reduced natural gas and steam usage.

Specific projects and their potential annual 

savings included:

• Reduce and control power boiler excess 

oxygen to save 66,000 cubic feet per hour 

(ft3/hr) of natural gas ($2 million)

• Insulate five large storage tanks to save 

25,000 pounds per hour (lb/h) of steam 

($661,500) 

• Repair steam leaks that had existed more 

than 1 year to save 7,700 lb/h ($263,000)

• Shift more black liquor evaporation to 

the 6-effect train to save 30,000 lb/h 

($793,000)

• Improve condensate collection by repairing 

leaks and improving collection coverage to 

65% and save 40,000 lb/h ($1,058,400)

• Clean heat exchangers (the savings have 

not been calculated but are believed to be 

significant).

Additional cogeneration opportunities 

include optimizing turbine pressure levels, 

improving steam turbine efficiency, and lower 

steam level for the users. The savings would 

come from incremental electricity cogeneration; however, there would be a penalty for 

additional fuel required.

To learn more about the plant-wide assessment program, visit the plant-wide assessment 

Web page at http://www.oit.doe.gov/

bestpractices/assessments.shtml or contact 

the EERE Information Center at 1-877-EEREINF (1-877-337-3463). 

 Projects Identified at the Georgia-Pacific Crossett Mill PWA

Annual Projected Savings Annual Projected Economic Impact

Fuel (MMBtu) Steam (MMBtu) Electricity 

(kWh)

Annual 

Savings ($) Capital Cost ($) Payback (Years)

Heating Recovery Projects

Heat recovery from bleach plant D effluents 890,000 665,000 2,400,000 1,600,000* 0.7*

Improved blow heat recovery and demineralized water heating 940,000 705,000 2,350,000 2,250,000* 1.0*

Bleach plant prechiller 15,000 11,000 900 61,400 124,200* 2.0*

Total 1,845,000 1,381,000 900 4,811,400 3,974,200

Operational Improvement Projects

S.T.E.P. Projects 1,500,000 900,000 4,800,000 Not evaluated** Not evaluated**

*Heat recovery projects will require a detailed cost and engineering analysis before implementation; capital costs are estimates only.

**The study did not evaluate implementation strategies and costs; therefore, the payback period has not been determined.

Mill Identifies Energy and Operational Improvements that May Save $9.6 Million Annually (continued from page 4)
Energy	Matters,	Winter	2005 7

Energy costs can have a significant effect 

on your plant’s bottom line. Volatile natural 

gas prices in the recent past have made it even 

more important that energy be used efficiently 

and effectively.

Researchers working at the Ernest 

Orlando Lawrence Berkeley National Laboratory recently completed a study that finds 

increased investment in energy efficiency, 

among other strategies, could help ease the 

threat of high natural gas prices over both the 

short and the long term.

The report demonstrates that energy efficiency and renewable energy can displace 

gas-fired electricity generation, reducing 

gas demand and putting downward pressure 

on natural gas prices and bills for consumers, including manufacturers. The simplified 

method may be applied to the impact of 

industrial energy efficiency on gas prices and 

bills.

Based in large part on a review of other 

modeling studies, the report is among the first 

to demonstrate that these results are broadly 

consistent with economic theory, results from 

other national energy models, and limited 

empirical evidence.

The report, “Easing the Natural Gas Crisis: Reducing Natural Gas Prices through 

Increased Deployment of Renewable Energy 

and Energy Efficiency”, was published by the 

national laboratory in January. 

The report reviews existing modeling 

studies and finds that these generally show 

that each 1% reduction in natural gas demand 

nationwide is likely to lead to a long-term 

wellhead price reduction of 0.8% to 2%. 

Some studies show more significant reductions, the authors report. 

The report also demonstrates the use of an 

analysis tool that can evaluate the potential 

effect energy efficiency and renewable energy 

strategies may have on natural gas prices and 

bills. The analytical tool is fueled by eight 

pieces of data. These are:

• Level of increased energy efficiency or 

renewable energy: This represents (in 

megawatt-hours—MWh) the incremental 

amount of energy efficiency and renewable 

energy advocated by various policymakers 

relative to a baseline “business-as-usual” 

scenario.

• Natural gas displacement ratio: This represents the share of natural gas generation 

displaced by energy efficiency or renewable energy. Displacement ratios evaluated 

by the report average between 34% and 

78%. The authors recommend using a gas 

displacement ratio of 40%.

• Natural gas heat rate: This converts the 

amount of displaced natural gas generation (in MWh) to an amount of displaced 

natural gas consumption (in millions of 

British thermal units—MMBtu). The 

authors recommend using a near-term heat 

rate of 9,000 Btu/kWh. They estimate that 

heat rates should drop to around 7,500 

Btu/kWh over the next five years.

• Total expected natural gas consumption: 

Estimates may be obtained from the latest 

Energy Information Administration (EIA) 

Annual Energy Outlook.

• Inverse price elasticity of supply: Converts 

the percentage reduction in U.S. gas consumption into a percentage reduction in 

the national average wellhead price. The 

authors recommend a range of 0.8 to 2 for 

this highly uncertain variable, with a “conservative” base-case value of 1.2.

• Business-as-usual wellhead gas price forecast: Forecasts may be obtained from the 

latest EIA Annual Energy Outlook.

• Delivered price conversion: The authors 

contend it is reasonable to assume that a 

$/MMBtu reduction in national wellhead 

prices will translate one-for-one into 

similar reductions in the national average 

delivered natural gas price, both to the 

electricity sector and to end users such as 

manufacturers.

• Regional multipliers: These estimate the 

differential effects of regional energy efficiency and renewable energy policy cases 

and vary by region and with time. The 

analysis uses the National Energy Modeling System, but the authors advocate further research on regional impacts to arrive 

at even more reliable multipliers.

Using these inputs to consider the potential national impact of energy efficiency and 

renewable energy strategies, the authors find 

that the “likely” national gas-bill savings from 

energy efficiency and renewable energy strategies ranges from about $5/MWh (assuming 

20% gas displacement and an inverse elasticity of 0.8) to about $45/MWh (assuming 80% 

gas displacement and an inverse elasticity of 

2.0). Even at the low end of this range ($5 to 

$20/Mwh) the authors conclude that the incremental benefits are substantial.

BestPractices, a program of the Industrial 

Technologies Program, works with industry to 

identify plant-wide opportunities for energy 

savings and process efficiency. Through the 

implementation of new technologies and 

systems improvements, companies across the 

U.S. are achieving immediate savings results. 

Visit http://www.oit.doe.gov/bestpractices/ for 

more information.

The Fan System Assessment Tool (FSAT) 

is the latest in the suite of DOE-developed 

software tools. With FSAT you can calculate 

the amount of energy your fan system uses, 

determine fan system efficiency, and quantify the savings potential of an upgraded fan 

system. 

The Industrial Technologies Program also 

offers Fan System Assessment Training, a 

1-day workshop highlighting the benefits of 

optimizing fan systems and examining fan 

system performance characteristics. If you 

are a plant engineer or are involved in operating and maintaining your plant’s fan systems, 

consider attending one of these training sessions. The training helps you determine the 

cost of operating fans in your facility, understand the interaction between the fan curve 

and the system curve, analyze the optimization potential of fan systems, and create an 

action plan to improve fan system efficiency 

and reliability in your plant. 

Also watch for Fan System Qualified Specialist Training coming to your area starting 

this spring. DOE is developing an additional 

level of training for industry professionals 

interested in becoming Qualified Fan System 

Specialists. By successfully completing this 

advanced training you will be recognized by 

DOE as a Specialist in the use of FSAT. As a 

Specialist, you can then apply the tool to help 

your plant or industrial customers identify 

ways to improve fan system efficiency. 

The pilot for this specialist training will 

take place in Arlington Heights, Illinois, 

April 12-14, and is limited to individuals 

with fan system expertise. For more information on this session, contact Bill Gentes at 

bgentes@amca.org , or 847-394-0150.

To learn about upcoming Fan System 

Assessment training in your area, visit the 

BestPractices training calendar. Or, contact 

the EERE Information Center at 1-877-

EERE-INF (1-877-337-3463), or http:

//www.eere.energy.gov/informationcenter.

Berkeley Lab Finds Industrial Energy Efficiency 

Strategies Can Help Ease Natural Gas Prices

Watch for Fan System 

Qualified Specialist 

Training Opportunities
This document was produced for the Office of Energy 

Efficiency and Renewable Energy at the 

U.S. Department of Energy (DOE) by the 

National Renewable Energy Laboratory, 

a DOE national laboratory.

DOE/GO-102005-2068 • March 2005

Printed with a renewable-source ink on paper containing 

at least 50% wastepaper, including 20% postconsumer 

waste

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BestPractices

The Industrial Technologies Program’s 

BestPractices initiative and its Energy 

Matters newsletter introduce industrial end 

users to emerging technologies and wellproven, cost-saving opportunities in motor, 

steam, compressed air, and other plant-wide 

systems. 

DOE Regional Office Representatives

■ David Godfrey, Atlanta, GA, 

 404-562-0568

■ Stephen Costa, Boston, MA, 

 617-565-1811

■ Brian Olsen, Chicago, IL, 

 312-886-8479

■ Jamey Evans, Denver, CO, 

 303-275-4813

■ Chris Cockrill, Seattle, WA, 

 816-873-3299

■ Bill Orthwein, Philadelphia, PA, 

 215-656-6957

 EERE INFORMATION 

 CENTER

 Do you have questions 

about using energy-efficient process 

and utility systems in your industrial 

facility? Call the Energy Efficiency and 

Renewable Energy (EERE) Information 

Center for answers, Monday through 

Friday 9:00 a.m. to 7:00 p.m. (EST).

HOTLINE: 877-EERE-INF

or 877-337-3463

Energy Matters

A STRONG ENERGY PORTFOLIO FOR A STRONG AMERICA

Energy efficiency and clean, renewable energy will 

mean a stronger economy, a cleaner environment, 

and greater energy independence for America. 

Working with a wide array of state, community, 

industry, and university partners, the U.S. Depart- ment of Energy’s Office of Energy Efficiency and 

Renewable Energy invests in a diverse portfolio of 

energy technologies.

Coming Events

This list represents only 11 of the 38 training opportunities that are available to you. For a 

complete listing, registration information, and updates, visit the BestPractices training web site at 

http://www.oit.doe.gov/bestpractices/training/textCalendar.shtml.

Steam System Assessment, Center Valley, PA, 

Mar 23, 2005 

For more information, contact David Althoff at 

dalthoff@state.pa.us or 717-705-0372

Pumping System Assessment, Stockton, CA, 

Apr 05, 2005 

For more information, contact Cheryl BoswellBarnes at cjb9@pge.com or 209-932-2529

Fan System Assessment, Austin, TX, 

Apr 05, 2005

For more information, contact Kathey Ferland 

kferland@mail.utexas.edu or 512-232-4823

 

Process Heating Assessment, Upper Darby, PA, 

Apr 06, 2005

For more information, contact Michael Sanders at 

mpsanders@sunocoinc.com or 215-339-7111

Pumping System Assessment, Campbell, CA, 

Apr 06, 2005

For more information, contact Cheryl BoswellBarnes at cjb9@pge.com or 209-932-2529

Fundamentals of Compressed Air Systems 

(Level 1), Baltimore, MD, Apr 07, 2005 

For more information, contact Brandon Arnold at 

barnold@energy.state.md.us or 410-260-7206

Process Heating Assessment, Tulare, CA, 

Apr 07, 2005

For more information, contact Gary Pikop at 

pikopgj@sce.com or 559-625-7127 

 

Fan Systems Specialist Qualification, Arlington 

Heights, IL, Apr 12-14, 2005

For more information, contact Bill Gentes at 

bgentes@amca.org or 847-394-0150 

Steam System Assessment, Stockton, CA, 

Apr 12, 2005

For more information, contact Cheryl BoswellBarnes at cjb9@pge.com or 209-932-2529

Advanced Management of Compressed Air 

Systems, Burlington, VT, Apr 19-20, 2005

For more information, contact Danielle McMahon at 

DMcMahon@veic.org or 802-860-4095, Ext. 1043 

Steam System Specialist Qualification, 

Milwaukee, WI, Apr 25-27, 2005

For more information, contact Tony Wright at 

wrightal@ornl.gov or 865-574-6678