Claim 5

“Biodiesel produces as much or more emissions of carbon dioxide, compared topetroleum diesel, and therefore is not any ‘greener’ than petroleum diesel.”

Jason Salazar, Andrew Peabody, Tram Nguyen, Samantha Tanner

Overview

Compare the emission of carbon dioxide in combustion of petrodiesel and biodiesel.

Decide whether biodiesel is in fact ‘greener’ than petrodiesel.

Compare the lifecycle of carbon dioxide emissions in petrodiesel and biodiesel.

Definitions of ‘greener’

Beneficial to the environment: green recycling policies.

Favoring or supporting environmentalism: green legislators who strengthened pollution controls.

The American Heritage® Dictionary of the English Language, Fourth Edition.

Petrodiesel Combustion

2C12H26 + 37O2 → 24CO2 + 26H2O + E

340g petrodiesel → 1060g carbon dioxide

1g petrodiesel → 3g carbon dioxide

Petrodiesel Combustion

2C12H26 + 37O2 → 24CO2 + 26H2O + E

340g petrodiesel → 1060g carbon dioxide

1g petrodiesel → 3g carbon dioxide

Biodiesel Combustion

C20H36O2 + 29O2 → 20CO2 + 18H2O + E

310g Biodiesel → 880g Carbon Dioxide

1g Biodiesel → 3g Carbon Dioxide

Biodiesel Combustion

C20H36O2 + 29O2 → 20CO2 + 18H2O + E

310g Biodiesel → 880g Carbon Dioxide

1g Biodiesel → 3g Carbon Dioxide

Petrodiesel vs. Biodiesel

1g of either petrodiesel or biodiesel both create about the same amount of carbon dioxide at 3grams.

Carbon dioxide is among the least effective (at heat trapping) of the greenhouse gases.

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0.5

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1.5

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2.5

3

Carbon Dioxide (g)

Petrodiesel

Biodiesel

Global Atmospheric Concentration of Greenhouse Gases (1992)

0

50

100

150

200

250

300

350

400

Carbon Dioxide (ppm) Methane (ppm) Nitrous Oxide (ppm) CFC-11 (ppm) CFC12 (ppm)

Intergovernmental Panel on Climate Change, 1996.

Photosynthesis

Photosynthesis

6CO2 + 12H2O + light → C6H12O6 + 6O2 + 6H2OCarbon Dioxide + Water + Light energy → Glucose + Oxygen + Water

Net CO2 Life Cycle Emissions

NREL, 1998.

References

The American Heritage® Dictionary of the English Language, Fourth Edition. An Overview of Biodiesel and Petroleum Diesel Life Cycles. National Renewable Energy Laboratory, 1998. Wikipedia: The Free Encyclopedia. 23 Oct. 2005. Wikimedia Foundation. 23 Oct. 2005 <http://en.wikipedia.org>. Intergovernmental Panel on Climate Change, Climate Change 1995: The Science of Climate Change Cambridge, UK:

Cambridge University Press, 1996. Campbell, Biology 7th Ed. New York: Benjamin Cummings, 2004. 18 Nov. 2006 http://www.wiseenergy.ca/index_files/biodiesel.htm 27 Nov. 2006 http://chemfinder.cambridgesoft.com

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