National Academies Press: OpenBook

Realizing the Energy Potential of Methane Hydrate for the United States (2010)

Chapter: Appendix D: Comparison of Units of Measurement of Amounts of Methane by Volume and Weight

« Previous: Appendix C: Presentations to the Committee
Suggested Citation:"Appendix D: Comparison of Units of Measurement of Amounts of Methane by Volume and Weight." National Research Council. 2010. Realizing the Energy Potential of Methane Hydrate for the United States. Washington, DC: The National Academies Press. doi: 10.17226/12831.
×

APPENDIX D
Comparison of Units of Measurement of Amounts of Methane by Volume and Weight

Amounts of methane can be reported either by volume or by weight. In the petroleum industry, amounts are given by volume, commonly as trillions (1012) of cubic feet (ft3) or TCF and billions (109) of ft3 (BCF) in the United States. Elsewhere in the world, where the metric system is used, the amounts are usually reported in cubic meters (m3). A convenient conversion factor is 35.3 ft3/m3.

In the oceanographic and atmospheric communities, amounts of methane are often reported by weight, that is, grams (g) or metric tons (106 g) usually with an appropriate prefix to simplify the use of exponents. Common expressions are teragrams (Tg = 1012 g), petagrams (Pg = 1015 g), and gigatons (Gt = 109 × 106 or 1015). The conversions from volume to weight or from weight to volume of methane are based on the relationship that a mol of methane, weighing 16 g, has a volume of 22.4 liters at standard temperature and pressure (STP). Useful conversion factors are 714 g/m3 and 20.2 g/ft3.

The following table compares amounts of methane in units of TCF, m3, and Pg in three categories: (1) assessments of amounts of conventional natural gas (methane); (2) estimates of the amounts of methane in methane hydrate; and (3) amounts of methane in the atmosphere.

Suggested Citation:"Appendix D: Comparison of Units of Measurement of Amounts of Methane by Volume and Weight." National Research Council. 2010. Realizing the Energy Potential of Methane Hydrate for the United States. Washington, DC: The National Academies Press. doi: 10.17226/12831.
×

TABLE D.1 Comparison of Methane Measurements

 

TCF

By Volume, m3

By Weight, Pg

Conventional natural gas (Methane)a

 

 

 

Global assessment of conventional methane in reserves and technically recoverable resources

16,000

4.4 × 1014

3.2 × 102

U. S. methane consumption in 2008

23

6.5 × 1011

4.7 × 10−1

Methane in methane hydrateb

 

 

 

Very early global estimates, based on many erroneous assumptions, of the methane content of gas hydrate

~35,000,000

~1018

~7.1 × 105

Recent range of global estimates of methane in methane hydrate

35,000 to 177,000

1 × 1015 to 5 × 1015

7.1 × 102 to 3.6 × 103

Mean MMS estimate of methane in hydrate in the Gulf of Mexico

21,000

6 × 1014

4.3 × 102

Mean U. S. Geological Survey estimate of technically recoverable methane from hydrate on the North Slope of Alaska

85.4

2.4 × 1012

1.7

Estimate of methane in hydrate, eastern Nankai Trough, Japan

40

1.14 × 1012

8.1 × 10−1

Atmospheric methanec

 

 

 

Atmospheric abundance of methane

~250

~7 × 1012

~5

Estimate of total global flux of methane from all sources entering the atmosphere per year

30

8.4 × 1011

0.6

Estimate of total global sink for all methane entering the atmosphere per year

29

8.1 × 1011

0.58

aSee Chapter 1.

bSee Chapter 2.

cFor discussion, see Kvenvolden, K. A. and B. W. Rogers. 2005. Gaia’s breath—global methane exhalations. Marine and Petroleum Geology 22: 579- 590.

Suggested Citation:"Appendix D: Comparison of Units of Measurement of Amounts of Methane by Volume and Weight." National Research Council. 2010. Realizing the Energy Potential of Methane Hydrate for the United States. Washington, DC: The National Academies Press. doi: 10.17226/12831.
×
Page 159
Suggested Citation:"Appendix D: Comparison of Units of Measurement of Amounts of Methane by Volume and Weight." National Research Council. 2010. Realizing the Energy Potential of Methane Hydrate for the United States. Washington, DC: The National Academies Press. doi: 10.17226/12831.
×
Page 160
Next: Appendix E: Program Authorizations and Appropriations FY 2000-2010 »
Realizing the Energy Potential of Methane Hydrate for the United States Get This Book
×
Buy Paperback | $58.00 Buy Ebook | $46.99
MyNAP members save 10% online.
Login or Register to save!
Download Free PDF

Natural gas, composed mostly of methane, is the cleanest of all the fossil fuels, emitting 25-50% less carbon dioxide than either oil or coal for each unit of energy produced. In recent years, natural gas supplied approximately 20-25% of all energy consumed in the United States. Methane hydrate is a potentially enormous and as yet untapped source of methane. The Department of Energy's Methane Hydrate Research and Development Program has been tasked since 2000 to implement and coordinate a national methane hydrate research effort to stimulate the development of knowledge and technology necessary for commercial production of methane from methane hydrate in a safe and environmentally responsible way.

Realizing the Energy Potential of Methane Hydrate for the United States evaluates the program's research projects and management processes since its congressional re-authorization in 2005, and presents recommendations for its future research and development initiatives.

  1. ×

    Welcome to OpenBook!

    You're looking at OpenBook, NAP.edu's online reading room since 1999. Based on feedback from you, our users, we've made some improvements that make it easier than ever to read thousands of publications on our website.

    Do you want to take a quick tour of the OpenBook's features?

    No Thanks Take a Tour »
  2. ×

    Show this book's table of contents, where you can jump to any chapter by name.

    « Back Next »
  3. ×

    ...or use these buttons to go back to the previous chapter or skip to the next one.

    « Back Next »
  4. ×

    Jump up to the previous page or down to the next one. Also, you can type in a page number and press Enter to go directly to that page in the book.

    « Back Next »
  5. ×

    Switch between the Original Pages, where you can read the report as it appeared in print, and Text Pages for the web version, where you can highlight and search the text.

    « Back Next »
  6. ×

    To search the entire text of this book, type in your search term here and press Enter.

    « Back Next »
  7. ×

    Share a link to this book page on your preferred social network or via email.

    « Back Next »
  8. ×

    View our suggested citation for this chapter.

    « Back Next »
  9. ×

    Ready to take your reading offline? Click here to buy this book in print or download it as a free PDF, if available.

    « Back Next »
Stay Connected!