DOE/EIA-0512(91)

Distribution Category UC-950

Manufacturing Consumption of Energy 1991

December 1994

Energy Information Administration

Office of Energy Markets and End Use

U.S. Department of Energy

Washington, DC 20585

This report was prepared by the Energy Information Administration, the independent statistical and analytical agency within

the Department of Energy. The information contained herein should not be construed as advocating or reflecting any policy

position of the Department of Energy or any other organization.
Contacts

General information about Energy Information Administration data on energy consumption can be obtained from

Lynda T. Carlson, Director of the Energy End Use and Integrated Statistics Division (EEUISD) (202-586-1112).

General information regarding the contents of this publication can be obtained from Dwight K. French, Chief of the

Transportation and Industrial Branch (202-586-1126), or John L. Preston (202-586-1128). Robert K. Adler (202-586-

1134; Internet BADLER@EIA.DOE.GOV), Mark A. Schipper (202-586-1136; Internet

MSCHIPPE@EIA.DOE.GOV), and Michael J. Margreta (202-586-2327; Internet MMARGRET@EIA.DOE.GOV)

are the contacts for estimation, analysis, and table preparation. Hattie Ramseur (202-586-1124) is the contact for

related energy consumption publications. The FAX number for all EEUISD personnel is 202-586-0018.

EIA maintains the Electronic Publishing System (EPUB) to allow the general public to electronically access the

tables found in this report and many of EIA’s statistical reports. EPUB can be accessed on (202) 586-2557 with

communication settings: baud rate of 300-19200, no parity, 8 data bits, 1 stop bit, full duplex, and terminal type

(ANSI, ANSI-BBS, VT-100, etc.).

ii Energy Information Administration/Manufacturing Consumption of Energy 1991
As part of the Energy Information Administration’s (EIA) mission to provide meaningful data, the consumption

surveys welcome comments from our customers. If you have any suggestions to make the data in this report

more useful to your needs, please contact Mark A. Schipper, MECS Survey Manager, at 202-586-1136, FAX

or Internet at the address below.

If you have any data or report-related requirements or suggestions for any of the other EIA consumption surveys,

please contact the appropriate survey manager directly, or use the address below.

Commercial Buildings Energy Consumption Survey (CBECS): Martha Johnson, Survey Manager, at 202-

586-1135 (Internet: MJOHNSON@EIA.DOE.GOV).

Residential Energy Consumption Survey (RECS): Wendel Thompson, Survey Manager, at 202-586-1119

(Internet: WTHOMPSO@EIA.DOE.GOV).

Residential Transportation Energy Consumption Survey (RTECS): Ron Lambrecht, Survey Manager, at 202-

586-4962 (Internet: RLAMBREC@EIA.DOE.GOV).

You are encouraged to provide your comments to the survey managers. Your feedback is important to us.

EI-63, Mail Stop 2G-090

1000 Independence Avenue, SW

Washington, DC 20585

FAX: 202-586-0018

Internet: MSCHIPPE@EIA.DOE.GOV

Energy Information Administration/Manufacturing Consumption of Energy 1991 iii
Contents Contents

Page

Executive Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ix

1. Introduction ..................................................................1

Manufacturing Energy Consumption Surveys ...........................................1

Organization of This Report .......................................................1

2. Energy Consumption in the Manufacturing Sector: An Overview ...........................3

Manufacturing Establishments .....................................................3

Energy Sources ................................................................4

Acquisition of Energy ...........................................................5

Use of Energy Sources ..........................................................6

Three General Measures of Energy Consumption ........................................6

Specific Measures of Energy Consumption .............................................7

Summary of Manufacturing Energy Throughput, 1991 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

3. Energy Consumption in the Manufacturing Sector, 1991 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Primary Consumption of Energy for All Purposes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Total Inputs of Energy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

End Uses for Heat, Power, and Electricity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

4. Manufacturer Capability To Switch Fuels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

Nonswitchable Minimum Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

Fuel-Switching Capability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

Discretionary Fuel Use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

Appendices

A. Detailed Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

B. Survey Design, Implementation, and Estimates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 437

C. Quality of the Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 459

D. Comparability of MECS Estimates with Other Series . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 467

E. MECS Estimates by International Standard Industrial Classification Codes . . . . . . . . . . . . . . . . . 481

F. Manufacturing Energy Consumption Survey Forms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 485

G. Descriptions of Major Industrial Groups and Selected Industries . . . . . . . . . . . . . . . . . . . . . . . . . 511

H. Map of U.S. Census Regions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 519

I. Metric Conversion Factors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 523

J. Related EIA Publications on Energy Consumption . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 527

Glossary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 533

iv Energy Information Administration/Manufacturing Consumption of Energy 1991
Tables

Page

A1. Total Primary Consumption of Energy for All Purposes by Census Region, Industry Group, and Selected

Industries, 1991: Part 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

A1. Total Primary Consumption of Energy for All Purposes by Census Region, Industry Group, and Selected

Industries, 1991: Part 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

A2. Total Consumption of LPG, Distillate Fuel Oil, and Residual Fuel Oil for Selected Purposes by Census

Region, Industry Group, and Selected Industries, 1991 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

A3. Total Primary Consumption of Combustible Energy for Nonfuel Purposes by Census Region, Industry

Group, and Selected Industries, 1991: Part 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49

A3. Total Primary Consumption of Combustible Energy for Nonfuel Purposes by Census Region, Industry

Group, and Selected Industries, 1991: Part 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55

A4. Total Inputs of Energy for Heat, Power, and Electricity Generation by Census Region, Industry Group,

and Selected Industries, 1991: Part 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61

A4. Total Inputs of Energy for Heat, Power, and Electricity Generation by Census Region, Industry Group,

and Selected Industries, 1991: Part 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67

A5. Total Consumption of Offsite-Produced Energy for Heat, Power, and Electricity Generation by Census

Region, Industry Group, and Selected Industries, 1991: Part 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73

A5. Total Consumption of Offsite-Produced Energy for Heat, Power, and Electricity Generation by Census

Region, Industry Group, and Selected Industries, 1991: Part 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79

A6. Total Inputs of Selected Byproduct Energy for Heat, Power, and Electricity Generation by Census

Region, Industry Group, and Selected Industries, 1991 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85

A7. Shell Storage Capacity of Selected Petroleum Products by Census Region, Industry Group, and Selected

Industries, 1991 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91

A8. Selected Energy Operating Ratios for Total Energy Consumption for Heat, Power, and Electricity

Generation by Census Region, Industry Group, and Selected Industries, 1991 . . . . . . . . . . . . . . . . . . . 97

A9. Total Primary Consumption of Energy for All Purposes by Census Region and Economic Characteristics

of the Establishment, 1991 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103

A10. Total Consumption of LPG, Distillate Fuel Oil, and Residual Fuel Oil for Selected Purposes by Census

Region and Economic Characteristics of the Establishment, 1991 . . . . . . . . . . . . . . . . . . . . . . . . . . 106

A11. Total Primary Consumption of Combustible Energy for Nonfuel Purposes by Census Region and

Economic Characteristics of the Establishment, 1991 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109

A12. Total Inputs of Energy for Heat, Power, and Electricity Generation by Census Region and Economic

Characteristics of the Establishment, 1991 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112

A13. Total Consumption of Offsite-Produced Energy for Heat, Power, and Electricity Generation by Census

Region and Economic Characteristics of the Establishment, 1991 . . . . . . . . . . . . . . . . . . . . . . . . . . 115

A14. Shell Storage Capacity of Petroleum Products by Census Region and Economic Characteristics of the

Establishment, 1991 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118

A15. Selected Energy Operating Ratios for Total Energy Consumption for Heat, Power, and Electricity

Generation by Census Region and Economic Characteristics of the Establishment, 1991 . . . . . . . . . . 121

A16. Components of Total Electricity Demand by Census Region, Industry Group, and Selected Industries,

1991 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 124

A17. Components of Onsite Electricity Generation by Census Region, Industry Group, and Selected Industries,

1991 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130

A18. Quantity of Electricity Sold to Utility and Nonutility Purchasers by Census Region, Industry Group, and

Selected Industries, 1991 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136

A19. Components of Total Electricity Demand by Census Region and Economic Characteristics of the

Establishment, 1991 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142

A20. Components of Onsite Electricity Generation by Census Region and Economic Characteristics of the

Establishment, 1991 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145

A21. Quantity of Electricity Sold to Utility and Nonutility Purchasers by Census Region and Economic

Characteristics of the Establishment, 1991 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 148

Energy Information Administration/Manufacturing Consumption of Energy 1991 v
Tables (Continued)

Page

A22. Total Quantity of Purchased Energy Sources by Census Region, Industry Group, and Selected Industries,

1991 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 151

A23. Quantity of Purchased Electricity, Steam, and Natural Gas by Type of Supplier, Census Region, Industry

Group, and Selected Industries, 1991 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 157

A24. Total Expenditures for Purchased Energy Sources by Census Region, Industry Group, and Selected

Industries, 1991 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 163

A25. Average Prices of Selected Purchased Energy Sources by Census Region, Industry Group, and Selected

Industries, 1991: Part 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 169

A25. Average Prices of Selected Purchased Energy Sources by Census Region, Industry Group, and Selected

Industries, 1991: Part 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175

A26. Total Quantity of Purchased Energy Sources by Census Region and Economic Characteristics of the

Establishment, 1991 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 181

A27. Quantity of Purchased Electricity, Steam, and Natural Gas by Type of Supplier, Census Region, and

Economic Characteristics of the Establishment, 1991 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 184

A28. Total Expenditures for Purchased Energy Sources by Census Region and Economic Characteristics of

the Establishment, 1991 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 187

A29. Average Prices of Selected Purchased Energy Sources by Census Region and Economic Characteristics

of the Establishment, 1991: Part 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 190

A29. Average Prices of Selected Purchased Energy Sources by Census Region and Economic Characteristics

of the Establishment, 1991: Part 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 193

A30. Total Primary Consumption of Energy for All Purposes by Value of Shipment Categories, Industry

Group, and Selected Industries, 1991 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 196

A31. Total Inputs of Energy for Heat, Power, and Electricity Generation by Value of Shipment Categories,

Industry Group, and Selected Industries, 1991 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 198

A32. Total Consumption of Offsite-Produced Energy for Heat, Power, and Electricity Generation by Value

of Shipment Categories, Industry Group, and Selected Industries, 1991 . . . . . . . . . . . . . . . . . . . . . . 200

A33. Total Primary Consumption of Energy for All Purposes by Employment Size Categories, Industry Group,

and Selected Industries, 1991 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 202

A34. Total Inputs of Energy for Heat, Power, and Electricity Generation by Employment Size Categories,

Industry Group, and Selected Industries, 1991 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 204

A35. Total Consumption of Offsite-Produced Energy for Heat, Power, and Electricity Generation by

Employment Size Categories, Industry Group, and Selected Industries, 1991 . . . . . . . . . . . . . . . . . . 206

A36. Total Inputs of Energy for Heat, Power, and Electricity Generation by Fuel Type, Industry Group,

Selected Industries, and End Use, 1991: Part 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 208

A36. Total Inputs of Energy for Heat, Power, and Electricity Generation by Fuel Type, Industry Group,

Selected Industries, and End Use, 1991: Part 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 230

A37. Total Inputs of Energy for Heat, Power, and Electricity Generation by Fuel Type, Census Region, and

End Use, 1991: Part 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 252

A37. Total Inputs of Energy for Heat, Power, and Electricity Generation by Fuel Type, Census Region, and

End Use, 1991: Part 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 254

A38. Selected Combustible Inputs of Energy for Heat, Power, and Electricity Generation and Net Demand

for Electricity by Fuel Type and End Use, 1991: Part 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 256

A38. Selected Combustible Inputs of Energy for Heat, Power, and Electricity Generation and Net Demand

for Electricity by Fuel Type and End Use, 1991: Part 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 278

A39. Selected Combustible Inputs of Energy for Heat, Power, and Electricity Generation and Net Demand

for Electricity by Fuel Type, Census Region, and End Use, 1991: Part 1 . . . . . . . . . . . . . . . . . . . . . 300

A39. Selected Combustible Inputs of Energy for Heat, Power, and Electricity Generation and Net Demand

for Electricity by Fuel Type, Census Region, and End Use, 1991: Part 2 . . . . . . . . . . . . . . . . . . . . . 302

vi Energy Information Administration/Manufacturing Consumption of Energy 1991
Tables (Continued)

Page

A40. Total Inputs of Energy for Heat, Power, and Electricity Generation by Energy Management

Program Sponsorship, Industry Group, Selected Industries, and Type of Energy Management

Program, 1991 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 304

A41. Total Inputs of Energy for Heat, Power, and Electricity Generation by Census Region, Industry

Group, Selected Industries, and Type of Energy Management Program, 1991 . . . . . . . . . . . . . . . . . . 326

A42. Total Inputs of Energy for Heat, Power, and Electricity Generation by Employment Size and Presence

of General Technologies, 1991 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 348

A43. Total Inputs of Energy for Heat, Power, and Electricity Generation by Value of Shipments and Presence

of General Technologies, 1991 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 348

A44. Total Inputs of Energy for Heat, Power, and Electricity Generation by Census Region, Industry Group,

Selected Industries, Presence of General Technologies, and Industry-Specific Technologies for Selected

Industries, 1991 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 349

A45. Total Inputs of Energy for Heat, Power, and Electricity Generation by Enclosed Floorspace, Percent

Conditioned Floorspace, and Presence of Computer Controls for Building Environment, 1991 . . . . . . 376

A46. Total Expenditures for Purchased Electricity, Steam, and Natural Gas by Type of Supplier, Census

Region, Industry Group, and Selected Industries, 1991 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 380

A47. Average Prices of Purchased Electricity, Steam, and Natural Gas by Type of Supplier, Census Region,

Industry Group, and Selected Industries, 1991 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 386

A48. Total Expenditures for Purchased Electricity, Steam, and Natural Gas by Type of Supplier, Census

Region, and Economic Characteristics of the Establishment, 1991 . . . . . . . . . . . . . . . . . . . . . . . . . . 392

A49. Average Prices of Purchased Electricity, Steam, and Natural Gas by Type of Supplier, Census Region,

and Economic Characteristics of the Establishment, 1991 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 395

A50. Selected Energy Operating Ratios for Total Energy Consumption for Heat, Power, and Electricity

Generation by Census Region and Economic Characteristics of the Establishment, 1991 . . . . . . . . . . 398

A51. Selected Energy Operating Ratios for Total Energy Consumption for Heat, Power, and Electricity

Generation by Census Region and Economic Characteristics of the Establishment, 1991 . . . . . . . . . . 411

A52. Nonswitchable Minimum Requirements and Maximum Consumption Potential by Census Region,

1991 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 422

A53. Capability to Switch from Electricity to Alternative Energy Sources by Industry Group, Selected

Industries, and Selected Characteristics, 1991 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 423

A54. Capability to Switch from Natural Gas to Alternative Energy Sources by Industry Group, Selected

Industries, and Selected Characteristics, 1991 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 425

A55. Capability to Switch from Distillate Fuel Oil to Alternative Energy Sources by Industry Group, Selected

Industries, and Selected Characteristics, 1991 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 427

A56. Capability to Switch from Residual Fuel Oil to Alternative Energy Sources by Industry Group, Selected

Industries, and Selected Characteristics, 1991 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 429

A57. Capability to Switch from Coal to Alternative Energy Sources by Industry Group, Selected Industries,

and Selected Characteristics, 1991 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 431

A58. Capability to Switch from LPG to Alternative Energy Sources by Industry Group, Selected Industries,

and Selected Characteristics, 1991 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 433

B1. Total Shipments of Energy Sources Produced Onsite from the Nonfuel Use of Other Energy Sources,

by Industry Group and Selected Industries, 1991 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 447

B2. Conversion of Physical Units to British Thermal Units . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 455

B3. Revisions to 1988 MECS Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 455

D1. Combined Industrial Energy Consumption Estimates and Sources of Information, 1991 . . . . . . . . . . . 469

D2. A Comparison of the Components of MECS and SEDR Estimates of Energy Consumption . . . . . . . . 471

E1. Manufacturing Consumption of Energy for Purposes of Heat, Power, and Electricity Generation by

International Standard Industrial Classification Codes, 1991 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 482

I1. Metric Conversion Factors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 525

Energy Information Administration/Manufacturing Consumption of Energy 1991 vii
Illustrations

Page

Figure 2.1. Largest Energy Consumers in the Manufacturing Sector, 1991 .........................3

Figure 2.2. Summary of Manufacturing Energy Throughput, 1991 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Figure 3.1. Primary Consumption of Energy for All Purposes by Major Industry Group, 1991 . . . . . . . . . . 13

Figure 3.2. Primary Consumption of Energy for All Purposes by Energy Source, 1991 . . . . . . . . . . . . . . . 14

Figure 3.3 Shares of Primary Consumption in Terms of Site and Embodied Electricity, 1991 . . . . . . . . . . . 14

Figure 3.4 Total Input Energy for Heat, Power, and Electricity Generation, 1991 . . . . . . . . . . . . . . . . . . . 15

Figure 3.5 Total Input Energy for Heat, Power, and Electricity Generation

by Major Industry Group, 1991 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

Figure 3.6 Byproduct Fuels Consumed by Manufacturers by Energy Source, 1991 . . . . . . . . . . . . . . . . . . 17

Figure 3.7 Consumption of Energy for Heat, Power, and Electricity Generation

by Manufacturing End Use, 1991 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

Figure 3.8 Consumption of Energy for Heat, Power, and Electricity Generation

by Manufacturing Direct Process End Use, 1991 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

Figure 3.9 Consumption of Energy for Heat, Power, and Electricity Generation

by Manufacturing Direct Non-Process End Use, 1991 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Figure 3.10 Consumption of Energy for Heat, Power, and Electricity Generation

by Major Industry Groups and Major End Uses, 1991 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Figure 3.11 Unreported End-Use Fuels Consumed for Heat, Power, and Electricity Generation, 1991 . . . . . . 20

Figure 4.1 Nonswitchable Minimum Requirements for Selected Fuels, 1991 . . . . . . . . . . . . . . . . . . . . . . 24

Figure 4.2 Switchable Quantities for Selected Fuels, 1991 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

Figure 4.3 Manufacturers’ Discretionary Ranges of Consumption

Resulting from Fuel-Switching Capability, 1991 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

Figure 4.4. Discretionary Use Rates by Selected Fuels, 1991 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

Figure 4.5. Average National Prices of Selected Purchased Fuels, 1991 . . . . . . . . . . . . . . . . . . . . . . . . . . 27

viii Energy Information Administration/Manufacturing Consumption of Energy 1991
Executive Summary

The Manufacturing Consumption of Energy 1991 report presents statistics about the energy consumption of the

manufacturing sector, based on the 1991 Manufacturing Energy Consumption Survey (MECS). The MECS is the

only comprehensive source of national-level data on U.S. manufacturing energy use. The 1991 MECS is the third

in an ongoing series of surveys conducted at 3-year intervals beginning in 1985. Pursuant to a provision of the

Energy Policy Act of 1992, the MECS will be conducted biennially beginning in 1994.

The MECS surveys a nationally representative sample of manufacturing establishments by means of mailed

questionnaires. The 1991 sample represented 98 percent of the U.S. manufacturing sector universe, which consists

of all manufacturing establishments in the 50 States and the District of Columbia. Compared with the 1988 MECS,

the designed sample size for 1991 was increased from 12,065 manufacturing establishments to 16,054 establishments.

The following are some of the key findings of the survey:

• The Primary Consumption of Energy for All Purposes in the manufacturing sector was 20.3 quadrillion Btu of

energy in 1991, compared with 20.1 quadrillion Btu in 1988. About two-thirds of this amount was used to

produce heat and power and to generate electricity, with about one-third being consumed as raw material input.

• The most common energy sources—natural gas, net electricity, coal, liquefied petroleum gas (LPG), residual and

distillate fuel oil, and coke—made up 64 percent of Primary Consumption.

• The amount of Total Inputs of Energy for Heat, Power, and Electricity Generation was 15.0 quadrillion Btu,

compared with 15.5 quadrillion Btu in 1988.

• The byproduct fuels—blast furnace gas, waste gas, petroleum coke, pulping liquor, wood byproducts, and waste

oils/materials—made up 28 percent of Total Inputs.

• End-use allocation was collected for about 65 percent of Total Inputs (9.7 quadrillion Btu). This consumption

was allocated to three groups of end uses: indirect uses, mainly boiler fuel (3.3 quadrillion Btu); direct process

uses, including use in motors, ovens, strip heaters, and kilns (5.0 quadrillion Btu); and direct non-process uses,

including facility space-conditioning, facility lighting, other facility support, onsite transportation, electricity

generation, and other miscellaneous uses (1.2 quadrillion Btu). Manufacturers consumed an additional 5.3

quadrillion Btu of energy for which end uses were not assigned. (The 1991 MECS collected data on end-use

allocation for the first time.)

• Manufacturers had the capability to switch 2.8 quadrillion Btu of all the electricity, natural gas, distillate and

residual fuel oils, coal, and LPG they used, representing 28 percent of their actual consumption. (Manufacturers

are said to have a fuel-switching capability if they are able to meet their requirements for heat, power, and

electricity generation by substituting one energy source for another within 30 days without modifying the

equipment that consumes the fuel and if they can resume the same level of production following the switch.)

• Manufacturers required an nonswitchable minimum of 7.0 quadrillion Btu of these energy sources, which was

72 percent of their actual consumption of these fuels. The fuels having the highest nonswitchable minimum

requirements were, in order, natural gas, electricity, and coal.

• Manufacturers often used coal and natural gas whenever possible, even though they could have used another

energy source instead. Price was apparently the primary reason that manufacturers switched energy sources

whenever they were able to do so.

Energy Information Administration/Manufacturing Consumption of Energy 1991 ix
1. Introduction

This report, Manufacturing Consumption of Energy 1991, provides estimates on energy consumption in the

manufacturing sector of the U.S. economy. These estimates are based on data from the 1991 Manufacturing Energy

Consumption Survey (MECS). This survey—administered by the Energy End Use and Integrated Statistics Division,

Office of Energy Markets and End Use, Energy Information Administration (EIA)—is the most comprehensive

source of national-level data on energy-related information for the manufacturing industries.

Manufacturing Energy Consumption Surveys

To determine how energy is being used in the manufacturing sector, EIA mails Forms 846 A through C to a

nationally representative sample of the establishments in the 50 States and the District of Columbia that transform

input materials or substances into new products, assemble components, or perform blending operations.1 In 1991,

these establishments numbered approximately 350 thousand, and the MECS sample represented 98 percent of energy

use in the U.S. manufacturing sector.

The 1991 MECS is EIA’s third survey of the manufacturing sector. Previous manufacturing surveys were conducted

in 1986 and 1989 (for reporting years 1985 and 1988, respectively). The next manufacturing survey will be

conducted for reporting year 1994, with subsequent MECS’s being conducted every 2 years thereafter.

The sample design of the 1991 and 1985 surveys differed somewhat from that of the 1988 survey, which necessitates

that care be exercised when comparing estimates from the three surveys. The 1988 sample represented 100 percent

of manufacturing energy use, but it included statistical adjustments to account for 2 percent of the population, namely

the smallest manufacturing establishments. The 1991 and 1985 samples represented 98 percent of the population,

without any statistical adjustment.

EIA conducts the MECS under the authority of the Federal Energy Administration Act of 1974, Public Law 93-275,

as amended, and Section 205 of the Department of Energy Organization Act, Public Law 95-91, as amended by

Section 3102 of the Omnibus Budget Reconciliation Act of 1986, Public Law 99-509.2 Section 171 of the Energy

Policy Act of 1992 mandates the MECS as a biennial collection.

The Industry Division of the Bureau of the Census collects the data and compiles it for EIA. All data reported to

the Bureau of the Census are confidential under the provisions of Section 9, Title 13, of the U.S. Code. EIA

gratefully acknowledges the cooperation of the respondents in supplying the information used to produce the

estimates in this report.

Organization of This Report

This introductory chapter is followed by a chapter giving an overall understanding of energy consumption in the

manufacturing sector, a chapter on some of the more important results of the 1991 MECS on energy consumption

and on manufacturing end uses, and a chapter on fuel-switching in the manufacturing sector. Data on manufacturing

energy consumption by end use were collected for the first time in the 1991 MECS. This MECS report is the first

to include fuel-switching data, which were published under separate cover for previous survey years.

1

The manufacturing sector is composed of establishments classified in SIC 20 through SIC 39 of the U.S. economy as defined by the Office

of Management and Budget (OMB). The manufacturing sector is a part of the industrial division, which also includes mining; construction; and

agriculture, forestry, and fishing. 2

The EIA also conducts energy consumption surveys in the residential, residential transportation, and commercial buildings sectors. These

surveys are the Residential Energy Consumption Survey (RECS), the Residential Transportation Energy Consumption Survey (RTECS), and the

Commercial Buildings Energy Consumption Survey (CBECS).

Energy Information Administration/Manufacturing Consumption of Energy 1991 1
The four chapters are followed by several technical appendices:

• Appendix A presents detailed statistical tables, providing measures of data reliability (Relative Standard

Errors) as factors in the rows and columns of the data tables rather than separately as in previous reports.

To better serve the user community, these tables were released to the public in May 1994 through EIA’s

electronic bulletin board system.

• Appendix B explains the sample design of and the estimation and implementation procedures for the MECS.

• Appendix C discusses the quality of the data.

A Guide to the Tables in This Report

Energy Consumption Tables A1-A6, A9-A13,

A30-A36

Storage Capacity Tables A7, A14

Energy Operating Ratios Tables A8, A15, A50,

A51

Electricity Demand Tables A16, A19

Electricity Generation Tables A17, A20

Electricity Sales Tables A18, A21

Purchased Energy Tables A22, A23, A26,

A27

Prices and Expenditures Tables A24, A25, A28,

A29, A46-A49

Consumption by:

End Use Tables A37-A39

Energy Management Tables A40, A41

Technology Tables A42-A45

Fuel-Switching Tables A52-A58

• Appendix D compares MECS estimates with

those provided by other sources.

• Appendix E presents one of the MECS consumption measures according to international

classification codes.

• Appendix F reproduces Forms EIA 846 A

through C, which were used to collect the

data on which all estimates in this report are

based, unless otherwise noted.

• Appendix G describes the major industrial

groups and selected industries.

• Appendix H provides a map of the U.S.

Census Regions.

• Appendix I presents metric conversion factors.

• Appendix J lists related energy consumption publications for readers interested in earlier MECS publications

or consumption reports for other sectors.

These appendices are followed by a glossary of statistical and engineering terms used in this report.

2 Energy Information Administration/Manufacturing Consumption of Energy 1991
2. Energy Consumption in the Manufacturing Sector:

An Overview

The manufacturing sector of the U.S. economy is composed of approximately 350 thousand establishments.

However, the number of establishments is of less significance for the MECS than their share of total energy

consumption because these establishments differ so dramatically from each other in their processes and products.

The energy-consuming characteristics of the manufacturing sector differ from those of the residential, commercial

building, and residential vehicle sectors in the energy sources manufacturers use, the ways in which they acquire that

energy, and the ways in which they use that energy. These complexities require complex measurement techniques.

Manufacturing Establishments

A manufacturing establishment is an economic unit at a single physical location where the mechanical or chemical

transformation of materials or substances into new products is performed.3 These operations are generally conducted

in facilities described as plants, factories, or mills and characteristically use power-driven machines and materialhandling equipment. Manufacturing also includes such activities as the assembly of components of manufactured

products and the blending of materials such as lubricating oil, plastics, resins, or liquors.

An establishment is not necessarily identical to a business concern or firm, either of which may consist of more than

one establishment. For example, an automobile manufacturer may be a firm having over 200 establishments, such

as stamping plants, auto assembly factories, and gear and axle plants. On the other hand, an automobile

manufacturer may be a firm having one establishment, with components coming from several other firms.

Manufacturing establishments fall into the industrial

Percent of Total Consumption

29.5

24.9

12.4

12.2

4.7

4.3

2.2

1.6

1.5

1.4

Petroleum and Coal

Chemicals

Paper

Metals (Steel, Iron)

Food

Glass, Stone and Clay

Lumber and Wood

Fabricated Metals

Textiles

0.0 5.0 10.0 15.0 20.0 25.0 30.0 35.0

Transportation Equipment

Source: Table A1 of this report.

Figure 2.1. Largest Energy Consumers in the

categories listed in the 1987 Standard Industrial Manufacturing Sector, 1991

Classification (SIC) system, developed by the Office of

Management and Budget.4 That system underlies all

establishment-based Federal statistics classified by

industry. The SIC system is used to promote the

comparability of establishment data describing various

facets of the U.S. economy. The levels of classification

in the SIC are division, major group, industry group, and

industry. The manufacturing sector contains 20 major

groups (SIC 20 through SIC 39), 139 industry groups, and

459 industries. Manufacturing establishments are

classified into industries based on the value of production

of their primary products. See Appendix G for a full

description of manufacturing groups and industries used in

this report.

Of the 10 largest energy consumers in the manufacturing

sector, the two largest were the: (1) petroleum and coal

and (2) chemicals and allied products major industry

groups (Figure 2.1).

3

Excluded from this definition of manufacturing establishment are construction, electric utilities, mining operations, agricultural production,

and forestry and fishery operations. 4

Office of Management and Budget, Standard Industrial Classification Manual, 1987 (Washington, DC, 1987).

Energy Information Administration/Manufacturing Consumption of Energy 1991 3
Energy Sources

Manufacturers consume large quantities of combustible

Energy Sources Used

in the Manufacturing Sector

Combustible Noncombustible

Solids Steam

Anthracite Electricity

Bituminous and Industrial hot water

subbituminous coal Solar energy

Coal coke Hydropower

Lignite Geothermal energy

Agricultural waste Wind power

Petroleum coke

Roundwood (wood cut

specifically for fuel use)

Waste materials

(wastepaper, packing

materials, etc.)

Wood chips, bark, and waste

Other solids

Gases

Natural gas

Acetylene

Blast furnace gas

Coke oven gas

Hydrogen

Waste and byproduct gases

(refinery gas, offgas, fuel

gas, vent gas, plant gas,

and still gas)

Other gases

Liquids

Distillate fuel oil

(numbers 1, 2, and 4 fuel

oils and diesel)

Kerosene

LPG (ethane, ethylene, propane,

propylene, butane, and butylene)

Motor gasoline

Pulping or black liquor

Residual fuel oil (numbers 5, 6,

navy special, and bunker c)

Waste oils and tars

Other liquids

and noncombustible energy sources. These energy

sources include such commonly known ones as natural

gas, electricity, coal, residual and distillate fuel oils, and

liquefied petroleum gases (LPG), as well as a wide

variety of uncommon energy sources. Moreover, some

materials, which might be thought of as energy sources,

are not counted as energy sources in the manufacturing

sector.

Examples of energy sources consumed in the

manufacturing sector but not in other sectors of the

economy include:

• Pulping liquor, or "black liquor," produced during

the transformation of wood to pulp in the Pulp

and Paper Industry

• Petroleum coke and still gas resulting from the

production of petroleum products in refineries

• Agricultural waste (like rice hulls and orchard

prunings), packing crates, discarded tires, and

other byproducts and waste materials

• Energy sources that manufacturers produce

themselves, such as electricity generated from

hydropower, wind power, solar power, and

geothermal sources.

On the other hand, materials that are often thought of as

energy sources in other sectors are not counted as such

in the manufacturing sector. For example, wood

consumed to produce paper, build furniture, or

manufacture lumber is excluded as an energy source in

the MECS. (However, wood that is consumed to

produce heat and power is counted as an energy source.)

A further anomaly occurs in petroleum refining in

accounting for crude oil. Petroleum refiners are treated

differently from other manufacturing establishments in

the MECS because their major economic activity is

transforming crude oil and other inputs into a wide

variety of products. Most of the major products, such as

distillate and residual fuel oils, motor gasoline, kerosene,

and LPG, are universally recognized and accounted for

by consumers as energy sources. However, some of

these products, such as asphalt, road oils, wax,

lubricating oils, solvents, and specialized petrochemical

feedstocks, are not considered to be energy sources.

4 Energy Information Administration/Manufacturing Consumption of Energy 1991
The MECS does not count crude oil inputs as consumption in refineries because doing so would duplicate the

consumption of the refinery energy products (like gasoline and LPG) that other sectors report. However, the MECS

does count the crude oil input to nonenergy products (like asphalt and road oil) because they will not be reported

by other sectors. For more information, see Appendix B, "Survey Design, Implementation, and Estimates."

Acquisition of Energy

Energy sources may arrive at an establishment from offsite, or they may be produced onsite. Energy sources

produced offsite arrive at an establishment in one of several ways. They may be:

• Purchased directly from an energy supplier and

Onsite Generation

of Electricity in 1991

Onsite generation of electricity accounted for 15 percent

of all the electricity generated (both offsite and onsite)

in the manufacturing sector in 1991. Of this amount,

electricity from:

• Cogeneration made up 88 percent

• Conventional generation from the fossil fuels

made up 9 percent

• Generation from renewable energy made up 3

percent.

Three major groups accounted for 84 percent of the

onsite generation of electricity:

• Paper and Allied Products (54 billion

kilowatthours)

• Chemicals and Allied Products (41 billion

kilowatthours)

• Petroleum and Coal Products (13 billion

kilowatthours).

paid for by the consuming establishment

• Purchased and paid for by a central purchasing

entity separate from the establishment but

delivered directly to the establishment

• Purchased by and transferred from another

establishment within the consuming

establishment’s company

• Delivered from another establishment within a

consuming establishment’s company, with the

consuming establishment being charged for the

energy consistent with the company’s accounting

policy

• Paid for in-kind.

For example, manufacturing establishments usually

purchase electricity directly from utilities as other

consumers do. In some situations, however, several

establishments of the same corporation and physically

located in the same geographic area may pool their

electricity purchases by having one of the establishments

serve as the "central purchaser." In this case, the

electricity is transferred from the central purchasing

authority to the consuming establishment. Some manufacturers also purchase steam and hot water from a nearby

manufacturer or transfer it from an establishment within the same corporation.

Manufacturers produce some of the energy they use onsite, as a byproduct of a manufacturing process, from onsite

coal mines or gas or oil wells, and through the generation of electricity. Coke oven gas, which is produced as a

byproduct when manufacturing coke from coal, is one example of energy being produced as a byproduct of a

manufacturing process. A second example is hydrogen, which is produced as a byproduct when the electrolysis of

brine (salt water, a nonenergy material) produces chlorine and caustic soda as the main products. Both coke oven

gas and hydrogen are used as energy sources.

Manufacturers generate electricity onsite in three ways:

• Cogeneration (the production of electrical energy and another form of useful energy, such as steam, through

the sequential use of energy)

• Conventional generation using combustible fuels

• Generation using solar power, wind power, hydropower, and geothermal sources.

Energy Information Administration/Manufacturing Consumption of Energy 1991 5
Use of Energy Sources

Manufacturers use energy sources in two major ways. The most widely understood use is to produce heat and power

and to generate electricity. Heat, power, and electricity consumption can be subdivided into three major end uses:

indirect use (boiler fuel), direct process uses, and direct non-process uses.5 Boiler fuel is used to transform one

source of energy into another (like steam). Direct process uses include energy for motors, ovens, strip heaters, and

kilns. Direct non-process uses include facility lighting and space-conditioning equipment.

The second way in which manufacturers use energy is as a raw material input to the manufacturing process or for

some other purpose other than for heat, power, and electricity generation.6 (These purposes are referred to as

"nonfuel uses" in this report.) For example, coal is consumed to produce coal coke. Also, natural gas is processed

to extract ethane, propane, and butane. These gases, in turn, are frequently used as raw material input to produce

fertilizers, pharmaceutical preparations, and other products.

Three General Measures of Energy Consumption

The MECS uses three general measures of energy consumption in the manufacturing sector: (1) Primary

Consumption of Energy for All Purposes, (2) Total Inputs of Energy for Heat, Power, and Electricity Generation,

and (3) Consumption of Offsite-Produced Energy for Heat, Power, and Electricity Generation. These measures are

used for different purposes:

• The Primary Consumption measure is most appropriate in discussions of the amount and impact of total U.S.

energy consumption.

• The Total Inputs measure is most useful in discussions of how energy use in the manufacturing sector

compares with energy use in the residential and commercial sectors.

• The Consumption of Offsite-Produced Energy measure is used to continue the data series, "Purchased Fuels

and Electric Energy," which was previously collected for EIA by the Bureau of the Census as a supplement

to its Annual Survey of Manufactures. These data were published for the reporting years 1974 through 1981.

Primary Consumption of Energy for All Purposes is the most comprehensive measure of energy consumption and

represents the first use of energy sources, no matter whether they are consumed as a fuel or as a nonfuel (mainly

raw material):

• It includes all energy produced offsite.

• It includes all energy produced onsite from nonenergy materials (such as sawdust from furniture production,

hydrogen from electrolysis of brine, and peanut shells from peanut processing).

• It includes net electricity, net steam, and net hot water.7

• It excludes all energy sources produced onsite as a result of the use of another energy source.

For example, the Primary Consumption measure includes the coal (an energy source purchased offsite) used at steel

works as a raw material to produce coal coke. However, the measure excludes the coal coke (an energy source

produced onsite as a result of the use of another energy source).

5

The 1991 MECS was the first collection of national-level end-use data.

6

Energy consumed as a raw material is frequently called a feedstock, although that terminology most often refers to petroleum-based inputs

and natural gas. 7

Net electricity, net steam, and net hot water are the sum of purchases, transfers in, and onsite production from renewables minus the quantities

sold and transferred out.

6 Energy Information Administration/Manufacturing Consumption of Energy 1991
Total Inputs of Energy for Heat, Power, and

Components and Measures

of Combustible Energy Consumption

Each of the three general measures of energy

consumption covers different components of

combustible energy consumption, which has six

components:

1. Energy produced offsite and consumed as a

fuel

2. Energy produced offsite and consumed for

nonfuel purposes

3. Energy produced onsite from nonenergy inputs

and consumed as a fuel

4. Energy produced onsite from nonenergy inputs

and consumed for nonfuel purposes

5. Energy produced onsite from energy products

and consumed as a fuel

6. Energy produced onsite from energy products

and consumed for nonfuel purposes.

Primary Consumption includes Components 1, 2, 3, and

4. Total Inputs includes Components 1, 3, and 5. Total

Consumption of Offsite-Produced Energy includes only

Component 1. (None of the three measures explicitly

includes Component 6 to avoid double counting.)

Electricity Generation is a less comprehensive measure

of energy consumption because it measures only the

energy used for its energy content:

• It includes all energy sources used to produce

heat and power and to generate electricity,

whether produced offsite or onsite.

• It includes net electricity, net steam, and net hot

water.

• It excludes all energy sources used as raw

material or other nonfuel uses.

For example, the Total Inputs measure includes coal

coke consumed onsite as a fuel, but it excludes the coal

that was consumed as a raw material input to produce

the coke.

Consumption of Offsite-Produced Energy for Heat,

Power, and Electricity Generation is the most

restrictive measure of the three:

• It includes all energy sources purchased or

transferred from offsite to produce heat and

power and to generate electricity.

• It excludes all energy produced onsite.

• It excludes all energy sources used as raw

materials or for other nonfuel purposes.

Specific Measures of Energy Consumption

In addition to the three general measures of energy consumption, this report provides specific measures related to

electricity, steam, and hot water consumption.

Embodied energy for electricity is the energy electricity suppliers use to generate the electricity consumed at the

site.8 During the generation process, large energy losses occur:

• When heat is converted into mechanical energy for turning electric generators

• When the power plant uses electricity for its own purposes, such as pumping water into elevated reservoirs

in pumped-storage hydroelectric plants

• When electricity is transmitted and distributed from the power plant to the consumer.9

8

Other products from EIA commonly use the term "primary energy" to denote energy measures that incorporate input energy used to generate

electricity. The MECS uses "embodied energy for electricity" for this concept to avoid confusion with the term "Primary Consumption of Energy." 9

Although energy losses also occur during the production of natural gas, fuel oil, and district heat, they are so small compared with those

occurring during the production of electricity that they are not considered in measuring primary energy consumption in this report.

Energy Information Administration/Manufacturing Consumption of Energy 1991 7
However, measuring the amount of the energy losses is complicated because their amount varies from year to year

and from utility plant to utility plant, depending on the conversion process, the particular mix of input energy sources

used in generation, and the efficiency of the utility plant. Since collecting data on these factors for each utility plant

would be unreasonable within the framework of EIA consumption surveys, the amount of energy consumed to

produce the electricity consumed onsite in any given year can only be estimated.

Evaluating the Energy Value of Electricity Consumption

Electricity consumption can be expressed in terms of either

• physical units, most commonly kilowatthours

• thermal units, most commonly British thermal units (Btu).

The physical unit is meant to give a clear understanding of the amount of a particular energy source being used,

while the thermal unit is a measure of convenience used to aggregate or compare various energy sources measured in different physical units. Converting kilowatthours of electricity to Btu is not a trivial issue, because the

amount of input energy needed to create a kilowatthour of electricity is far greater than the amount of useful energy

in the kilowatthours at its point of use. Therefore, meaningful conversions of electricity use from kilowatthours to

Btu can be given in terms of:

• Site (point-of-use) electricity, at the universal value of 3,412 Btu per kilowatthour. This value is useful to

engineers, energy managers, and others trying to improve energy efficiency.

• Embodied (primary) electricity, at a value that reflects the content of the energy inputs used to produce the

electricity. This rate is most useful to policymakers and analysts who are considering global resources and

environmental issues.

Estimates of embodied electricity should be treated with caution. They should be considered rough alternative

measures to site energy as indicators of the importance of electricity as a manufacturing energy source.

EIA bases this estimate on the approximate annual amount of combustible fuels (coal, natural gas, and petroleum

products) used by steam-electric generating plants, which generate most of the Nation’s electricity.10 In 1991, U.S.

steam-electric utility plants are estimated to have used approximately 10,352 Btu of conventional-fuel energy to

generate 1 kilowatthour of electricity—or approximately 3.03 Btu of conventional-fuel energy to generate 1 Btu of

electricity, since 3,412 Btu equals 1 kilowatthour of electricity.11 Accordingly, in this report, estimates of site

electricity consumption in kilowatthours can be converted to estimates of embodied energy consumption by using

10,352 as the conversion factor. For example, in Table A1, Part 1, the Food and Kindred Products Industry group

consumed 49,536 million kilowatthours of electricity. Multiplying this estimate by 10,352 Btu per kilowatthour

would yield 513 trillion Btu, the amount of embodied energy used to generate that amount of electricity.

Estimates of embodied electricity can only be approximations of the amount of energy actually used to generate

electricity, especially in the manufacturing sector, because many manufacturers use energy sources other than the

combustible fuels. For example, the electricity-intensive industries, such as aluminum, are concentrated in areas

where electricity can be generated from energy sources other than conventional fuels, usually hydropower. Thus,

the accuracy of the conversion factor varies across industry groups.

Electricity demand is the amount of electricity actually consumed onsite, regardless of where or how it was

produced. It is a useful measure of electricity consumption without regard to the consumption of other energy

sources. Electricity demand is estimated in this report as the sum of electricity purchases, transfers in, and total

onsite generation minus the quantities of electricity sold or transferred offsite.

10The fossil fuels, especially coal, provide the principal energy sources for the generation of electricity. Nuclear and hydroelectric power are

used to a lesser extent, with wood/waste, wind, geothermal, and solar energy supplying only a small amount of energy for electricity generation. 11"Table A8. Approximate Heat Rates for Electricity," Monthly Energy Review, August 1994, p. 165.

8 Energy Information Administration/Manufacturing Consumption of Energy 1991
Net electricity is estimated for each manufacturing establishment as the sum of purchased electricity, transfers in,

and generation from noncombustible renewable resources minus the quantities of electricity sold and transferred

offsite. Thus net electricity excludes the quantities of electricity generated or cogenerated onsite from combustible

energy sources. The estimates of net electricity appear in the estimates of Total Primary Consumption for All

Purposes (Table A1) and Total Inputs of Energy for Heat, Power, and Electricity Generation (Table A4).

Electricity receipts is the amount of electricity purchased and transferred into the establishment. This measure is

used so that the MECS estimates of offsite-produced energy will be consistent with the Census Bureau’s definition

of "purchased fuels and electricity," on which the Bureau of the Census collected and published data from 1974

through 1981. The estimates for Electricity Receipts appear in the estimates of Total Consumption of OffsiteProduced Energy for Heat, Power, and Electricity Generation (Table A5).

Net steam is the sum of purchases, transfers in, and generation from renewable energy sources minus the quantities

sold and transferred out.

Net hot water is the sum of purchases and transfers in, minus the quantities of hot water sold and transferred out.

Estimates of net steam and net hot water are not shown separately in the MECS but are included in the "Other"

column of tables that show Primary Consumption and Total Inputs. The estimates of Offsite-Produced Energy for

Heat, Power, and Electricity Generation include the steam and hot water purchased by and transferred to a

manufacturing establishment in order to be consistent with the Census Bureau’s definition of "purchased fuels and

electricity."

Energy Information Administration/Manufacturing Consumption of Energy 1991 9
3. Energy Consumption

in the Manufacturing Sector, 1991

In 1991, the amount of energy consumed in the manufacturing sector was as follows:

• Primary Consumption of Energy for All Purposes was 20.3 quadrillion Btu of energy, or about one-third of

the total end-use energy consumed by the U.S. economy.

• Total Inputs of Energy for Heat, Power, and Electricity Generation were 15.0 quadrillion Btu.

The end uses for which manufacturing establishments consumed most of this energy were boiler fuel, direct

processing, and direct non-processing (facility support).

Primary Consumption of Energy for All Purposes

The amount of Primary Consumption of Energy for All Purposes in 1991 was 20.3 quadrillion Btu, compared with

20.1 quadrillion Btu in 1988 and 17.5 quadrillion Btu in 1985. The shares of consumption for each of the commonly

known energy sources remained stable during the 6-year period:

• The share for natural gas was 30 percent in 1991, 29 percent in 1988, and 30 percent in 1985.

• The share for net electricity was 12 percent in all 3 years.12

• The share for coal was 10 percent in 1991, 12 percent in 1988, and 14 percent in 1985.

• The share for liquefied petroleum gas (LPG) was 8 percent in 1991 and 5 percent in 1985 and 1988.

• The share for other energy sources was 41 percent in 1991, 42 percent in 1988, and 40 percent in 1985.13

Six industry groups accounted for 88 percent (17.8

Source: Table A1 of this report.

Quadrillion Btu

1.0

2.5

5.1

6.0

0.9

2.5

2.4

Food

Paper

Chemicals

Petroleum and Coal

Stone, Clay, and Glass

Primary Metal

Other Manufacturing

0.0 2.0 4.0 6.0 8.0

Figure 3.1. Primary Consumption of Energy

for All Purposes by Major

Industry Group, 1991

quadrillion Btu) of Primary Consumption of Energy for

All Purposes: food and kindred products; paper and allied

products; chemicals and allied products; petroleum and

coal products; stone, clay, and glass products; and primary

metals (Figure 3.1).

About two-thirds of Primary Consumption of Energy for

All Purposes (13.9 quadrillion Btu) was used to produce

heat and power and to generate electricity, with about onethird (6.4 quadrillion Btu) being consumed as raw material

input (Table A3).

12"Net electricity" is the sum of purchases, transfers in, and generation from noncombustible renewable resources, minus quantities sold and

transferred out. 13Changes in shares for coal and LPG from 1988 to 1991 were statistically significant at the 0.05 level. Changes in shares for natural gas,

net electricity, and other energy sources were nonsignificant.

Energy Information Administration/Manufacturing Consumption of Energy 1991 13
The most common energy sources—natural gas, net electricity, coal, liquefied petroleum gas (LPG), residual and

distillate fuel oil, and coke—made up 64 percent of Primary Consumption. Making up the remaining 36 percent of

Primary Consumption were still gas, waste gas, petroleum coke, pulping liquor, and other energy that respondents

indicated they had used as Primary Energy, as well as crude oil inputs to such materials as asphalt and road oil

(Figure 3.2).

Natural Gas. Natural gas was the energy source most

Source: Table A1 of this report.

Quadrillion Btu

6.1

2.4

2.0

1.6

0.5

0.3

0.1

7.3

Natural Gas

Net Electricity

Coal

LPG

Residential Fuel Oil

Coke

Distillate Fuel Oil

Other

0.0 2.0 4.0 6.0 8.0

Figure 3.2. Primary Consumption of Energy

for All Purposes by Energy

Source, 1991

heavily consumed at the manufacturing site in 1991,

accounting for 30 percent of Primary Consumption.

Natural gas consumption is heavily concentrated in the

chemicals and allied products major industry group, where

it is consumed as a fuel and as a feedstock. This major

industry group accounted for about 36 percent (2.2

quadrillion Btu) of the Primary Consumption of natural

gas (Table A1). About one-fourth of the natural gas consumed by the chemicals and allied products major industry

group (0.6 quadrillion Btu) was used as an energy raw

material (Table A3). Natural gas is used as a raw material

in the preparation of numerous products, but one of the

heaviest uses is for manufacturing nitrogenous fertilizers.

Electricity. Net electricity was the second most heavily

consumed single energy source by manufacturers in 1991,

accounting for 12 percent of site Primary Consumption

(2.4 quadrillion Btu).14 However, taking into account the

amount of energy used to generate the site net electricity

Source: Table A1 of this report.

12

36

11

11

30

29

29

9

9

24

Site Energy Consumption Embodied Energy Consumption

Net

Electricity

(Site)

Net

Electricity

(Embodied)

Natural Gas

Petroleum Other

Natural Gas

Petroleum

Other

Coal

and

Coke

Coal

and

Coke

20.3 Quadrillion Btu 25.1 Quadrillion Btu

Figure 3.3. Percent of Primary Consumption

in Terms of Site and Embodied

Electricity, 1991

(the embodied energy consumption for net electricity), net

electricity accounted for 29 percent of site energy

consumption (Figure 3.3).

Four major industry groups consumed 54 percent (1.3

quadrillion Btu) of Primary Consumption of net electricity:

food and kindred products, paper and allied products,

chemicals and allied products, and primary metal

industries. Of these, the primary metal major industry

group, which includes primary aluminum, was the heaviest

consumer. The primary aluminum industry uses large

quantities of electricity to produce aluminum ingots from

alumina. In 1991, net electricity provided 77 percent of

the aluminum industry’s site energy consumption. (Taking

into account the energy used to generate that site

electricity, it accounted for 91 percent of the industry’s

embodied energy consumption.)

Coal. The 1991 Primary Consumption of coal was 2.0 quadrillion Btu. Coal is heavily consumed by the blast

furnaces and steel mills industry to produce coke. Coking operations accounted for 0.8 quadrillion Btu, or 40 percent

of Primary Consumption of coal.

14Unless otherwise specified, all estimates of electricity consumption shown in this report are given in terms of site energy.

Energy Information Administration/Manufacturing Consumption of Energy 1991 14
LPG. Liquefied petroleum gases (LPG) are consumed mostly as a raw material by manufacturers. The largest users

are chemical industries that use LPG as petrochemical feedstock. An example is the production of ethylene from

ethane. Of the total 1991 Primary Consumption of 1.6 quadrillion Btu, 1.5 quadrillion Btu (94 percent) was used

as a raw material.

Distillate and Residual Fuel Oils. The Primary Consumption of distillate and residual fuel oils continued at a

relatively low level in 1991. Residual fuel oil accounted for only 0.5 quadrillion Btu and distillate fuel oil, 0.1

quadrillion Btu. Total fuel oil consumption accounted for only about 3 percent of Primary Consumption, which also

was the case in both the 1985 and 1988 MECS.

Other Energy Sources. Other energy sources accounted for 36 percent (7.3 quadrillion Btu) of Primary

Consumption. Those energy sources included net steam and other energy that respondents indicated was used as

a fuel and raw material input (4.4 quadrillion Btu). In addition, the estimate has been supplemented by the quantity

of energy consumed by the petroleum refining industry to produce final products that are not normally considered

to be energy sources (asphalt, road oil, solvents, lubricants, and waxes). Those products accounted for 40 percent

(2.9 quadrillion Btu) of the other energy sources. (See Appendix B for a discussion of the rationale of this

procedure.)

Total Inputs of Energy

The amount of Total Inputs of Energy for Heat, Power, and Electricity Generation in 1991 was 15.0 quadrillion Btu,

compared with 15.5 quadrillion Btu in 1988 and 13.6 quadrillion Btu in 1985. Between 1988 and 1991, the shares

of consumption for each of the commonly known energy sources remained stable:

• The share for natural gas was 34 percent in 1988

Source: Tables A4 and A6 of this report.

Quadrillion Btu

5.5

4.2

2.4

1.2

0.6

0.4

0.1

0.1

0.5

Natural Gas

Byproducts

Net Electricity

Coal

Coke

Residual Fuel Oil

LPG

Distillate Fuel Oil

Other

0.0 2.0 4.0 6.0

Figure 3.4. Total Input Energy for Heat, Power,

compared with 37 percent in 1991. and Electricity Generation, 1991

• The share for net electricity was 15 percent in

1988 compared with 16 percent in 1991.

• The share for coal and coke was 13 percent in

1988 compared with 12 percent in 1991.

• The share for petroleum products was 6 percent in

1988 compared with 4 percent in 1991.

• The share for byproducts was 28 percent in 1988

and 1991.

• The share for other energy sources was 3 percent

in 1988 compared with 4 percent in 1991.15

The shares for the various energy sources in 1985 cannot be compared with shares for 1988 and 1991 because data

on the amount of byproduct fuels consumed in 1985 were published only in aggregate form.

Of the eight specific types of energy measured by Total Inputs, natural gas was the dominant energy source, followed

by byproduct fuels (Figure 3.4). Energy sources produced offsite made up 72 percent of Total Inputs of Energy for

Heat, Power, and Electricity Generation. Fuels produced onsite made up the remaining 28 percent.

15Changes in shares for natural gas, coal and coke, petroleum products, and other energy sources from 1988 to 1991 were statistically

significant at the 0.05 level. Changes in shares for net electricity and byproducts were nonsignificant.

Energy Information Administration/Manufacturing Consumption of Energy 1991 15
Consumption by Major Industry Group

Source: Table A4 of this report.

Quadrillion Btu

1.0

2.5

3.0

3.0

2.3

3.3

Food

Paper

Chemicals

Petroleum and Coal

Primary Metal

Other Manufacturing

0.0 1.0 2.0 3.0 4.0

Figure 3.5. Total Input Energy for Heat,

Power, and Electricity Generation

by Major Industry Group, 1991 The major industry groups consuming the most energy for

heat, power, and electricity generation were food and

kindred products, paper and allied products, chemicals and

allied products, petroleum and coal products, and primary

metal industries (Figure 3.5). Industries vary in the

proportion of energy they use for heat, power, and

electricity generation and the proportion they use for raw

materials. Some industries, like the food and kindred

products and the paper and allied products industries,

consume large amounts of energy for heat, power, and

electricity generation and small amounts of energy for raw

material. Other industries, such as the chemicals and

petroleum industries, consume large amounts of energy as

raw material.

Food and Kindred Products. In the food and kindred

products major industry group, the 1991 estimates of Primary Consumption and Total Inputs are nearly identical at

1.0 quadrillion Btu. This close correspondence is because the food industry consumes virtually all its energy as a

fuel to process food for distribution and consumes negligible amounts of energy as a raw material.

Paper and Allied Products. Estimates of Primary Consumption and Total Inputs are also similar for the paper and

allied products major industry group (about 2.5 quadrillion Btu for each) because this group, too, consumes only

small amounts of energy sources as energy raw material. It should be noted that the primary raw material input for

the production of pulp and paper is wood. However, pulping wood is not counted as an energy source in the MECS

because it is considered by manufacturers to be a nonenergy raw material input. Therefore, both Primary

Consumption and Total Inputs include wood byproducts.

Chemicals and Petroleum Industries. The chemicals and allied products and the petroleum and coal products

major industry groups clearly illustrate these industries’ heavy use of energy as a raw material. The 1991 Primary

Consumption for chemicals and allied products was 5.1 quadrillion Btu, of which 2.4 quadrillion Btu was consumed

as an energy raw material. Total Inputs for chemicals and allied products (3.0 quadrillion Btu) excludes the energy

consumed as a raw material. The petroleum and coal products major industry group was quite similar, with a

Primary Consumption of 6.0 quadrillion Btu, of which 3.0 quadrillion Btu was consumed for nonfuel use, as raw

material input to nonenergy products.

Byproduct Fuels

Byproduct fuels—blast furnace gas, waste gas, petroleum coke, pulping liquor, wood byproducts, and waste

oils/materials—made up 28 percent of Total Inputs of Energy for Heat, Power, and Electricity Generation (Figure

3.6). Industries differ in the amount of byproduct energy they use, with the blast furnace, petroleum refining, and

paper and pulp industries being the largest consumers of byproduct fuels.

Blast Furnace Industry. The blast furnace industry consumed 1.6 quadrillion Btu of input energy in 1991. This

industry commonly produces two byproduct fuels—blast furnace and coke oven gas. Blast furnace gas is a

combustible waste gas generated in a blast furnace when iron ore is being reduced with coke to metallic iron. In

addition, most steel works produce much of their own coke. Coke oven gas is a combustible mixture of gases

produced by the carbonization of coal in a coke oven. These gases are "recycled" and consumed onsite as a fuel.

Of the total input energy consumption of this industry, 27 percent (0.4 quadrillion Btu) was provided by these byproduct energy sources (Table A6).

Energy Information Administration/Manufacturing Consumption of Energy 1991 16
Petroleum Refineries. The 1991 input energy

Source: Table A6 of this report.

Quadrillion Btu

0.4

1.6

0.6

0.9

0.7

0.1

Blast Furnace Gas

Waste Gas

Petroleum Coke

Pulping Liquor

Wood Byproducts

Waste Oils/Materials

0.0 0.5 1.0 1.5

Figure 3.6. Byproduct Fuels Consumed by

Manufacturers by Energy Source,

1991

requirement for the petroleum refining industry was 2.9

quadrillion Btu. That energy was consumed as a fuel to

refine crude oil into useful products. Waste gas (still gas)

and petroleum coke are byproducts of the petroleum

refining process. Waste gas is any form or mixture of gas

produced in refineries by distillation, cracking, reforming,

and other refining processes. The principal constituents of

waste gas are methane, hydrogen, ethane, ethylene,

propane, propylene, butane, and butylene. Petroleum coke

is a solid residue that is high in carbon content and low in

hydrogen. It is the final product of thermal decomposition

in the condensation process in cracking crude oil. Some

of these byproducts are sold, but most are recycled into

the refining process and consumed as a fuel. In 1991,

these byproducts accounted for 1.8 quadrillion Btu, or 62

percent of the total input energy requirement of the petroleum refining industry.

Paper and Allied Products Industries. The paper and allied products industries use enormous amounts of wood

to produce paper. Byproducts of the wood used to produce paper consist of pulping liquor and wood chips, bark,

and wood waste. Pulping liquor is the alkaline spent liquor removed from the digester in the process of chemically

pulping wood. After evaporation, the liquor is burned in a recovery furnace that provides heat and permits the recovery of certain basic chemicals from the liquor. Nearly all pulping liquor is consumed onsite, as are most of the wood

byproducts. Total 1991 input energy for this major industry group was 2.5 quadrillion Btu. Of that amount, pulping

liquor accounted for 0.9 quadrillion Btu and wood chips, bark and wood waste, for 0.3 quadrillion Btu. Thus, 48

percent of the total input energy requirement of the paper and allied products major industry group was met by these

byproduct energy sources.

End Uses for Heat, Power, and Electricity

In 1991, 65 percent of the Total Inputs of Energy for Heat, Power, and Electricity Generation in the manufacturing

sector was allocated to three groups of end uses: indirect uses (mainly boiler fuel), direct process uses, and direct

non-process uses. The remaining 35 percent of energy inputs was unallocated. The 1991 MECS was the first

collection of national-level end-use data.

End-Use Consumption of Energy

The manufacturing sector used 9.7 quadrillion Btu of natural gas, electricity, coal, residual and distillate fuel oils,

and LPG to produce the heat, power, and electricity needed for:

• Boiler fuel, which is used to transform one source of energy into another (like steam)

• Direct process uses, including use in motors, ovens, strip heaters, and kilns

• Direct non-process uses, including facility heating, ventilation, and air-conditioning (HVAC); facility lighting,

other facility support; onsite transportation; electricity generation; and other miscellaneous uses.

The manufacturing sector as a whole used the most energy for direct process uses (Figure 3.7).

Energy Information Administration/Manufacturing Consumption of Energy 1991 17
Boiler Fuel

Quadrillion Btu

9.7

3.3

5.0

1.2

0.2

Total

Boiler Fuel

Direct Process Uses

Not Reported

0.0 2.0 4.0 6.0 8.0 10.0 12.0

Source: Table A36 of this report.

Direct Non-Process Uses

Figure 3.7. Consumption of Energy for Heat,

Power, and Electricity Generation

Approximately one-third (3.3 quadrillion Btu) of reported by Manufacturing End Use, 1991

1991 end-use consumption was consumed as boiler fuel,

energy that was then transformed into steam or some other

energy source. This transformation of energy describes the

largest specific end use of reported energy consumed by

manufacturing establishments.

Transformation of energy is not usually considered an

energy use because steam has subsequent end uses.

Steam, the predominant output from industrial boilers, has

multiple uses in most manufacturing establishments and is,

therefore, difficult for manufacturers to measure and

quantify since the energy content depends upon both

temperature and pressure. In the surgical and medical

instruments industry, for example, steam can be used to

sterilize medical products such as sutures and syringes.

Meanwhile, high-pressure steam can also be used to

produce electricity or can be used by other industrial

Quadrillion Btu

5.0

3.1

0.1

1.3

0.3

0.1

Total Process

Process Heating

Cooling/Refrigeration

Machine Drive

Electro-Chemical

Other

0.0 2.0 4.0 6.0 8.0

Source: Table A36 of this report.

Figure 3.8. Consumption of Energy for Heat,

Power, and Electricity Generation

by Manufacturing Direct Process

End Use, 1991

processes or non-processes that require thermal energy.

Direct Process End Uses

In 1991, over half (5.0 quadrillion Btu) of reported enduse consumption was used to transform raw material

inputs into production outputs. The MECS identified four

distinct direct processes—process heating, process

cooling/refrigeration, machine drive (motors),16 electrochemical processes—and a group of other unspecified

processes. The three most energy-intensive direct process

end uses were process heating, machine drive, and electrochemical processes (Figure 3.8).

Process heating, which accounted for 62 percent (3.1

quadrillion Btu) of all reported direct process

consumption, encompasses numerous uses. For example:

• The aluminum industry uses process heating to hold molten aluminum in crucibles after the electro-chemical

process (the reduction process) of splitting alumina into molten aluminum metal and oxygen.

• The steel industry uses process heating to melt scrap metal in electric-arc furnaces.

• The food industry uses process heating to dry food residual (such as yeast extract) for resale as livestock feed.

Machine drive, used for equipment such as industrial air compressors and pumps, consumed 1.3 quadrillion Btu (27

percent) of reported direct process consumption and represented the second largest reported direct process use of

energy. Of that 1.3 quadrillion Btu, electricity accounted for 1.2 quadrillion Btu (88 percent) of consumption.

Electro-chemical use of energy ranked third in the reported consumption of energy for direct process uses. Over

0.3 quadrillion Btu of electricity, concentrated in the primary metal and chemicals and allied products industries, were

consumed in that process. Of that amount of purchased and generated electricity, the primary metal industries

16Machine drive transforms thermal or electrical energy into mechanical energy.

Energy Information Administration/Manufacturing Consumption of Energy 1991 18
accounted for 229 trillion Btu (63 percent) and the chemicals and allied products industries consumed 114 trillion

Btu (32 percent). Within the primary metal industries, the primary aluminum industry consumed 216 trillion Btu

(60 percent) of electro-chemical use. This industry uses the electro-chemical process to reduce alumina to molten

aluminum metal and oxygen (Table A38).

To improve the energy efficiency of their direct process operations, manufacturing establishments participated in

various demand-side management (DSM) and other energy management programs (Table A40). From 1989 through

1991, their activities and percent of participation, expressed in terms of the total input energy use represented by

participating establishments, were as follows: installing or retrofitting motors to achieve better energy efficiency (36

percent), improving the efficiency of process heating (34 percent), and improving the efficiency of process cooling

(15 percent).

Direct Non-Process End Uses

Quadrillion Btu

1.2

0.5

0.2

0.1

0.1

0.4

0.1

Total Non-Process

Facility HVAC

Facility Lighting

Other Facility Support

Onsite Transportation

Electricity Generation

Other

0.0 0.4 0.8 1.2 1.6

Source: Table A36 of this report.

Less than 8 percent

of all reported

end-use energy

consumption.

Figure 3.9. Consumption of Energy for Heat,

Power, and Electricity Generation

by Manufacturing Direct NonProcess End Use, 1991

Of the 9.7 quadrillion Btu of consumption for which end

uses were reported, only 1.2 quadrillion Btu was

designated for direct non-process uses. Less than 8

percent (0.7 quadrillion Btu) of energy consumption in

manufacturing establishments was directly related to

facility use (Figure 3.9). Process uses of energy affect

some facility-related use of energy. Heat that radiates

from manufacturing processes may negate, or restrict,

facility HVAC use of energy. For example, glass melters

found in the glass industries create a large amount of heat

energy that is then transferred to the surrounding working

environment. Since cooling that environment is not

usually considered economically viable, the proximity of

the manufacturing process may reduce the likelihood that

the enclosed manufacturing floorspace is conditioned. In

addition, those indirect transfers of radiant heat from

processing uses to the surrounding environment are not

measured.

To improve the energy efficiency of their direct non-process operations, manufacturing establishments participated

in various DSM and other energy management programs (Table A40). From 1989 through 1991, their activities and

percent of participation, expressed in terms of the total input energy use represented by participating establishments,

were as follows: improving the efficiency of facility lighting (36 percent) and installing equipment to improve

facility HVAC systems (23 percent).

Industry Patterns of Energy Consumption for Different End Uses

Since the production process is commonly considered the driving force behind the manufacturing sector, most

industries consume most of their energy for direct process uses and consume relatively little for non-process uses.

In 1991, direct non-process uses accounted for roughly 1.2 quadrillion Btu, or 12 percent of reported energy

consumption. One of the heaviest users of energy for direct processes was the stone, clay, and glass major industry

group, which consumed 0.7 quadrillion Btu (90 percent of all the energy it consumed) for direct process uses. This

industry group is a heavy user of process heating, which is an energy-intensive end use.

Other industries, however, used most of the energy they consumed for heat, power, and electricity for boiler fuel,

such as the paper and allied products industries and the pulping and paper-making processes industries. The paper

and allied products industries, which reported 1.2 quadrillion Btu for end-use consumption, reported consuming 66

percent of its reported inputs as boiler fuel, and only 26 percent in direct process uses and 7 percent in direct nonprocess uses, with the remaining 1 percent undiscerned. That configuration of consumption was also characteristic

Energy Information Administration/Manufacturing Consumption of Energy 1991 19
of the pulping and paper-making processes, where large quantities of steam are required to remove water from paper

sheets (Figure 3.10).

Most industries use only a small percentage of the energy

Total

Food

Paper

Chemicals

Petroleum

Stone, Clay,

Industrial

0 20 40 60 80 100 120

Percent of End-Use Consumption

Boiler

Process

NonNot

Uses

Process Uses

Reported

Fuel

and Coal

and Glass

Machinery

Source: Table A36 of this report.

Figure 3.10. Consumption of Energy for

Heat, Power, and Electricity

Generation by Major Industry

Groups and Major End Uses,

1991

they consume for non-process end uses. However, in

those industries where assembly-type manufacturing takes

place in large, environmentally controlled buildings, it can

be quite a large percentage. Examples are the furniture and

fixtures industries (32 percent), transportation equipment

industries, such as automobile plants (25 percent), or

computer and office equipment industries (43 percent).

Unallocated End-Use Consumption

of Energy

In addition to the 9.7 quadrillion Btu of the most common

energy sources that manufacturers consumed for boiler

fuel, direct process uses, and direct non-process uses,

manufacturers consumed 5.3 quadrillion Btu of energy for

which end uses were not assigned. Eight byproduct

energy sources formed the major components of the 5.3

quadrillion Btu of unallocated end-use consumption:

waste gas, pulping liquor (black liquor), blast furnace/coke

oven gases, petroleum coke, coal coke, wood byproducts,

waste oils/materials, and net steam (Figure 3.11).

While consumption of byproducts was not allocated to a

Quadrillion Btu

5.3

0.4

1.6

0.6

0.9

0.6

0.7

0.1

0.2

0.3

Total

Blast Furnace Gas

Waste Gas

Petroleum Coke

Pulping Liquor

Coal Coke

Wood Byproducts

Waste Oils/Materials

Net Steam

Other

0.0 1.0 2.0 3.0 4.0 5.0 6.0

Source: Tables A4, A6, A36, and D2 of this report.

Unreported Fuel

Figure 3.11. Unreported End-Use Fuels

Consumed for Heat, Power, and

Electricity Generation, 1991

specific end use, those energy sources generally have a

finite number of uses at a manufacturing establishment.

For example:

• Coal coke is generally consumed as a fuel for its

heat content and as a reducing agent for smelting

iron ore in the blast furnaces and steel mills

industry, accounting for 0.5 quadrillion Btu (92

percent) of the unallocated coal coke.

• Pulping liquor, generated onsite at paper industry

establishments, is generally consumed in recovery

boilers to generate heat and recover catalysts for

use in the pulping process.

• Waste gas is generally consumed for process

heating in petroleum refineries, according to a

1984 American Petroleum Institute study.17

17Chemical and Engineering News, Energy Use by Petroleum Industry, June 9, 1986.

Energy Information Administration/Manufacturing Consumption of Energy 1991 20
Summary

In 1991, the Primary Consumption of Energy for All Purposes in the manufacturing sector was 20.3 quadrillion Btu

of energy, compared with 20.1 quadrillion Btu in 1988. About two-thirds of this amount was used to produce heat

and power and to generate electricity, with about one-third being consumed as raw material input to produce

nonenergy products. The most common energy sources—natural gas, net electricity, coal, LPG, residual and distillate

fuel oil, and coke—made up 64 percent of Primary Consumption.

The amount of Total Inputs of Energy for Heat, Power, and Electricity Generation was 15.0 quadrillion Btu in 1991,

compared with 15.5 quadrillion Btu in 1988. The byproduct fuels—blast furnace gas, waste gas, petroleum coke,

pulping liquor, wood byproducts, and waste oils/materials—made up 28 percent of Total Inputs.

End-use allocation was collected for about 65 percent of Total Inputs (9.7 quadrillion Btu). This consumption was

allocated to three groups of end uses: indirect uses, mainly boiler fuel (3.3 quadrillion Btu); direct process uses,

including use in motors, ovens, strip heaters, and kilns (5.0 quadrillion Btu); and direct non-process uses, including

facility HVAC, facility lighting, other facility support, onsite transportation, electricity generation, and other

miscellaneous uses (1.2 quadrillion Btu). Manufacturers consumed an additional 5.3 quadrillion Btu of energy for

which end uses were not assigned.

Energy Information Administration/Manufacturing Consumption of Energy 1991 21
4. Manufacturer Capability To Switch Fuels

Manufacturers can often best adapt to changes in economic conditions, energy supply interruptions, and other

constraints on energy use by switching fuels. For the MECS, manufacturers are said to have a fuel-switching

capability if they are able to meet their requirements for heat, power, and electricity generation by substituting one

energy source for another within 30 days without modifying the equipment that consumes the fuel and resuming the

same level of production following the switch.

Although all manufacturers have certain minimum requirements for energy sources that cannot be replaced by another

energy source, many manufacturers have some fuel-switching capability. The degree of a manufacturer’s capability

depends only on the characteristics of the equipment and practical limitations to switching, such as binding take-orpay agreements with energy suppliers and environmental regulations that limit the amounts of potential replacements

that could have been consumed. Much of the fuel-burning equipment that manufacturers use is capable of burning

more than one energy source.

The 1991 MECS determined fuel-switching capability for six commonly known energy sources and looked at the

extent to which manufacturers exercised their ability to choose the mix of energy sources at their discretion.

Nonswitchable Minimum Requirements

Generally, a manufacturing establishment uses a certain quantity of an energy source that cannot be replaced by any

other energy source, at least not within a 30-day period. The reasons for nonswitchable quantities are as varied as

the types of production environments themselves. Among the practical limitations to switching are the characteristics

of the establishment and the equipment itself, which would require, at the very least, significant modifications

disruptive to production. Other switching deterrents are existing energy-supply contracts and environmental

restrictions. In addition, the physical properties of certain energy sources could produce a desirable or harmful effect

on the product.

For example, consider a manufacturing plant that consumed 2.0 million cubic feet of natural gas to produce

automobile bodies. Of that amount, 500 thousand (0.5 million) cubic feet of natural gas was nonswitchable because

it was consumed in paint-drying ovens that required natural gas. Using any other energy source would have changed

the tint of the pigments in the paint, rendering the products unsalable. The remaining 1.5 million cubic feet of

natural gas was switchable because it was consumed in a boiler that could burn either natural gas or residual fuel

oil, and the switch between those two energy sources could have taken place within a few hours.

In 1991, manufacturers required an nonswitchable minimum of 7.0 quadrillion Btu of electricity receipts,18 natural

gas, distillate and residual fuel oils, coal, and liquefied petroleum gas (LPG), 72 percent of actual consumption of

these fuels (Figure 4.1). This amount represents actual consumption decreased by the quantity of the energy sources

that would no longer have been required if all ascertained switching from that energy source had occurred. This

amount also includes the quantity of 1991 consumption for which switching capability was not ascertained.

The following are manufacturers’ nonswitchable requirements for the most common energy sources, stated as a

percentage of the actual consumption of each energy source:

• Electricity: 98 percent of actual consumption

• Natural gas: 65 percent of actual consumption

18The estimate of electricity receipts represents those quantities of electricity that were produced offsite and available onsite for consumption,

but it does not include electricity generated onsite, nor has it been adjusted to account for any quantities that might have been resold or transferred

to another establishment.

Energy Information Administration/Manufacturing Consumption of Energy 1991 23
• Distillate fuel oil: 80 percent of actual

Source: Table A52 of this report.

Quadrillion Btu

2.39

3.59

0.11

0.23

0.66

0.06

Electricity Receipts

Natural Gas

Distillate Fuel Oil

Residual Fuel Oil

Coal

LPG

0.00 0.50 1.00 1.50 2.00 2.50 3.00 3.50 4.00

Figure 4.1. Nonswitchable Minimum

Requirements for Selected Fuels,

1991

consumption

• Residual fuel oil: 55 percent of actual

consumption

• Coal: 55 percent of actual consumption

• LPG: 53 percent of actual consumption.

Fuel-Switching Capability

In 1991, manufacturers had the capability to switch 2.8

quadrillion Btu of the most common energy sources,

representing 28 percent of actual consumption. The

energy sources for which fuel-switching capability is most

desirable are the petroleum-based fuels. Since the mid1970’s, concern about U.S. dependency on crude oil imports and adherence to environmental restrictions have

prompted manufacturers to concentrate on reducing their consumption of petroleum-based fuels.

According to the Bureau of the Census, manufacturers’ 1978 consumption of residual and distillate fuel oils

accounted for 17 percent of total offsite-produced energy for heat, power, and electricity generation.19 By 1991,

those same petroleum-based energy sources accounted for only 4 percent of the total. This substantial decrease was

likely due to manufacturers’ replacement of petroleum-based fuels with other energy sources. By 1991,

manufacturers had little capability remaining to replace petroleum-based fuels with other energy sources.

Natural gas has long been viewed as a prime alternative to petroleum-based fuels because of its widespread

availability, supply reliability, clean-burning quality, and reduced storage capacity. However, a fuel-switching

capability for natural gas is also necessary because of occasional supply disruptions. For example, natural gas

production at the wellhead may be disrupted or the supplier may not be able to deliver the required amount of natural

gas. Moreover, the natural gas supply may be interrupted during periods of extreme cold weather, when residential

and commercial customers receive priority service at the sacrifice of manufacturers. Finally, the demand for natural

gas sometimes exceeds supply in certain parts of the country, especially in the Northeast and Midwest, forcing

manufacturers to use some other energy source for awhile.

The energy sources that had the greatest potential for switching were natural gas, with coal a distant second (Figure

4.2). The following were manufacturers’ fuel-switching capabilities for the most common energy sources:

• About 17.0 billion kilowatthours of electricity receipts could have been replaced by other energy sources, 2

percent of actual consumption (Table A53). The switching potential for electricity is quite limited because

most manufacturing equipment is not designed to permit switching between electricity and a combustible

energy source. Most of the capability to replace electricity by combustible energy sources is in the form of

redundant combustors that can be used in place of electric-powered equivalents.

• About 1.9 trillion cubic feet of natural gas was switchable, 35 percent of actual consumption. The primary

replacement energy sources for natural gas were distillate fuel oil, coal coke, and residual fuel oil (Table

A54). No single energy source could have decreased the consumption of natural gas even halfway to its

minimum required level of 3.5 trillion cubic feet, but the dominant single replacement source, distillate fuel

oil, could have replaced 0.7 trillion cubic feet (40 percent) of the natural gas that was switchable.

19Before 1985, Total Inputs for Heat, Power, and Electricity Generation were not collected. However, for those earlier years, the Bureau of

the Census did tabulate total consumption of offsite-produced energy for heat, power, and electricity generation, which is a key part of Total Inputs

because most petroleum-based fuels are produced offsite.

Energy Information Administration/Manufacturing Consumption of Energy 1991 24
• About 4.8 million barrels of distillate fuel oil was

Source: Table A52 of this report.

Quadrillion Btu

0.06

1.92

0.03

0.19

0.53

0.05

Electricity Receipts

Natural Gas

Distillate Fuel Oil

Residual Fuel Oil

Coal

LPG

0.00 0.25 0.50 0.75 1.00 1.25 1.50 1.75 2.00

Figure 4.2. Switchable Quantities for

switchable, 20 percent of actual consumption. Selected Fuels, 1991

Natural gas was the dominant replacement source

for distillate fuel, capable of replacing 3.2 million

barrels (Table A55).

• About 29.3 million barrels of residual fuel oil was

switchable, 45 percent of actual consumption, with

natural gas capable of replacing 19.5 million

barrels (Table A56).

• About 23.6 million short tons of coal (45 percent

of actual consumption) could have been replaced

by other energy sources (Table A57).

• About 13.3 million barrels of LPG (47 percent of

actual consumption) was switchable, with natural

gas capable of replacing 11.4 million barrels (Table

A58).

Discretionary Fuel Use

Fuel-switching capability allows manufacturers substantial flexibility in choosing their mix of energy sources. The

consumption of a given energy source can be maximized if all possible switching into that energy source were to

take place. At the other extreme, consumption can be minimized if all possible switching from that energy source

were to take place. (This value is the nonswitchable minimum requirement discussed earlier.) The interval defined

by these maximum and minimum limits represents the discretionary range of consumption for an energy source,

resulting from fuel-switching capability. Actual consumption lies within that discretionary range. A preference for

a given energy source is indicated when its actual consumption approaches its maximum consumption potential, as

in the case of both natural gas and coal (Figure 4.3). Conversely, a preference for other energy sources is indicated

when actual consumption approaches its minimum required level.

For example, one manufacturer in the 1991 MECS used 3.0 million Btu of a given energy source, 1.0 million Btu

of which could have been replaced by some other energy source and 2.0 million Btu of which could not have been

replaced. In addition, the manufacturer could have used the given energy source to replace 2.0 million Btu of other

energy sources. If the manufacturer had chosen to use the given energy source whenever possible, consumption of

the energy source would have been at the maximum consumption level of 5.0 million Btu. If the manufacturer had

chosen to use a substitute energy source whenever possible, the manufacturer’s consumption of the given energy

source would have been at the minimum consumption level of 2.0 million Btu. Thus, the maximum potential is 3.0

million Btu above the minimum level, and this amount (3.0 million Btu) represents the discretionary range of

consumption. Since the actual consumption is 1.0 million Btu above the minimum level, the depth into the

discretionary range is 1.0/3.0 or 33 percent, which is the discretionary use rate of the given energy source.

One of the more interesting summary statistics that can be developed from the estimates of actual consumption,

minimum consumption, and maximum consumption is the discretionary use rate. The discretionary use rate is a

measure of the extent to which manufacturers elected to consume a given energy source when they could have

consumed some other energy source, given their fuel-switching capabilities and production levels of 1991. (See

Appendix B for an explanation and formula of the discretionary use rate.)

If manufacturers always choose to use an energy source whenever possible, the discretionary use rate for that energy

source would be 100 percent. On the other hand, if manufacturers choose to minimize their consumption of a given

energy source by always using other energy sources whenever possible, the discretionary use rate would be 0 percent.

Energy Information Administration/Manufacturing Consumption of Energy 1991 25
Source: Table A52 of this report.

Quadrillion Btu

6.06

2.62

1.32 1.27 1.17 0.89

Natural Electricity Coal Residual Distillate LPG 0.00

1.00

2.00

3.00

4.00

5.00

6.00

5.51

2.45

2.39

0.11

0.14 0.23

0.41 0.11

0.06

3.59

0.66

1.18

Discretionary

Range

Maximum Consumption

Minimum Consumption

Actual Consumption

Gas Oil Oil

Figure 4.3. Manufacturers’ Discretionary Ranges of Consumption

Resulting from Fuel-Switching Capability, 1991

A look at the discretionary use rates for the commonly known fuels shows that manufacturers often used natural gas

and coal whenever possible in 1991. In contrast, they seldom used distillate fuel oil and LPG, even when they could

have done so (Figure 4.4). The discretionary use rates for the commonly known energy sources are as follows:

• Coal ranked highest in discretionary use with a

Source: Table A52 of this report.

Percent of Discretionary Use

26

77

3

18

80

6

Electricity Receipts

Natural Gas

Distillate Fuel Oil

Residual Fuel Oil

Coal

LPG

0 10 20 30 40 50 60 70 80 90

Figure 4.4. Discretionary Use Rates

robust rate of 80 percent. The consumption of coal by Selected Fuels, 1991

was close to its short-term maximum level, given

the levels of production in 1991 (Table A52).

• Natural gas ranked second in discretionary use with

a rate of 77 percent.

• Electricity had a relatively low use rate of 26

percent, indicating that manufacturers preferred

other energy sources when available. Electricity

receipts rated a distant second to natural gas in

terms of fuel demand by manufacturers, as they

totaled 2.5 quadrillion Btu (0.7 trillion kilowatthours).

• The extremely low discretionary use rates for

distillate fuel oil (3 percent) and LPG (6 percent)

indicate that manufacturers generally avoided consuming these energy sources whenever possible.

• The discretionary use rate for residual fuel oil was 18 percent. Although that use rate was considerably

higher than those for distillate fuel oil and LPG, it was still low enough to indicate a preference for other

energy sources over residual fuel oil.

Price would appear to be the primary reason that manufacturers exercised their option to switch fuels (Figure 4.5).

For example, the discretionary use of coal was due in part to the fact that manufacturers had no price incentive to

switch to any other energy sources. At $1.78 per million Btu, the national price of coal was substantially below that

of any competing energy source.

Energy Information Administration/Manufacturing Consumption of Energy 1991 26
Furthermore, manufacturers had no price incentive to replace natural gas with distillate fuel, even though that switching capability existed in 1991. Nationally, the price of natural gas stood at $2.30 per million Btu, while the price

of distillate fuel oil was $5.63 per million Btu (Table A25). The price of distillate fuel was uniformly higher than

the price of natural gas in the four Census Regions, with the difference never being less than $2.00 per million Btu.

In certain geographic regions of the United States,

Source: Table A25 of this report.

Dollars Per Million Btu

13.49

2.30

5.63

2.54

1.78

4.91

Electricity Receipts

Natural Gas

Distillate Fuel Oil

Residual Fuel Oil

Coal

LPG

0.00 2.00 4.00 6.00 8.00 10.0012.0014.00

Figure 4.5. Average National Prices

of Selected Purchased Fuels,

1991

however, price incentives existed to replace natural gas

with residual fuel oil. Residual fuel oil could have

replaced 0.6 trillion cubic feet (34 percent) of the 1.9

trillion cubic feet of natural gas that was switchable. At

$2.54 per million Btu, the national price of residual fuel

oil was only marginally higher than that of natural gas.

However, in the Northeast Census Region, the reported

average price of natural gas hit $3.39, compared with

$2.90 for residual fuel oil, thereby yielding a gas-oil price

ratio of 1.17. The gas-oil price ratios were 1.10, 0.87, and

0.90 for the Midwest, South, and West Census Regions,

respectively. Although price incentives existed in the

Northeast and Midwest to switch from natural gas to

residual fuel oil, these two regions consumed 0.7 trillion

cubic feet of switchable natural gas, of which 0.3 trillion

cubic feet (35 percent) could have been replaced by less

expensive residual fuel oil in 1991 (Table A54). In these

regions, manufacturers chose natural gas over residual fuel

oil despite favorable price incentives.

Summary

For the MECS, manufacturers are said to have a fuel-switching capability if they are able to meet their requirements

for heat, power, and electricity generation by substituting one energy source for another within 30 days without

modifying the equipment that consumes the fuel and if they can resume the same level of production following the

switch.

In 1991, manufacturers required an nonswitchable minimum of 7.0 quadrillion Btu of electricity, natural gas, distillate

and residual fuel oils, coal, and LPG, which was 72 percent of their actual consumption of these fuels. The fuels

having the highest nonswitchable minimum requirements were, in order, natural gas, electricity, and coal.

Manufacturers had the capability to switch 2.8 quadrillion Btu of these energy sources, representing 28 percent of

their actual consumption. Natural gas was the energy source having the greatest potential for switching.

Manufacturers often used coal and natural gas whenever possible, even though they could have used another energy

source instead. Price would seem to be the primary reason that manufacturers exercised their option to switch fuels.

Energy Information Administration/Manufacturing Consumption of Energy 1991 27
28 Energy Information Administration/Manufacturing Consumption of Energy 1991