 |
|
Posted on Mar. 09, 2009
By Roger Pielke, Jr.
Carbon Dioxide Emissions Simplified
Ed. note: This piece also appears today on Roger Pielke Jr.'s science policy blog, Prometheus.The mathematics of United States carbon dioxide emissions are not actually that complicated. The figure below from the U.S. Energy Information Agency shows that the 5,991 million metric tonnes (MMt) of carbon dioxide emitted by the U.S. came from 3 sources: coal, natural gas, and petroleum (click here to see the graph). Each of these fossil fuels, plus renewables and nuclear power make up the total energy consumption in the United States. Energy consumption is measured using a unit call a “quad” which means a quadrillion BTUs. In 2007 the United States used 101.4 quads of energy (data). This amount of energy can be broken down by source (click here to see the graph). The 15.2 quads of energy from nuclear and renewable sources resulted in negligible carbon dioxide emissions. The amount of carbon dioxide emitted due to each quad of fossil fuel energy depends upon the source, as their carbon intensities differ. For the analysis that follows I use the following values, distilled from the EIA information provided here. Coal = 94 MMt Carbon Dioxide per Quad Natural Gas = 53 MMt Carbon Dioxide per Quad Petroleum = 65 MMt Carbon Dioxide per Quad Thus, to calculate total U.S. carbon dioxide emissions simply requires multiplying quads of energy by carbon dioxide per quad and summing across the three fuels. This simple math results in the following: (94 * 22.8 [Coal]) + (53 * 23.6 [Natural Gas]) + (65 * 39.8 [Petroleum]) = 5,981 MMt carbon dioxide This total compares quite well with the total of 5,991 MMt carbon dioxide reported for 2007 by EIA (see figure above). We can use this information to ask some straightforward questions about how an emissions reduction target of 14 percent below 2005 levels (5,095 MMt carbon dioxide) might be reached by 2020. We can do a bit of hypothetical “stress testing” of these numbers, by asking, in theory, what sort of actions might lead to reaching the emissions reductions target. Before we do this, we do need to make a guess as to 2020 US energy consumption. The EIA projects that energy consumption will grow at a rate of 0.5 percent per year. Because GDP growth is expected to be higher than this rate, it already builds in an assumption of gains in energy efficiency. But let’s use the EIA estimate, which suggests that US energy consumption in 2020 will be 108.6 quads, of which 21 quads will come from renewables plus nuclear energy, representing a growth of about 40 percent on top of 2007 values. This leaves 87.2 quads to be produced by fossil fuels. Here are a few examples of the effects of different hypothetical strategies: 1) What would happen if all coal consumption were to be replaced with natural gas? Answer: In 2020 total emissions would be 5,110 MMt carbon dioxide, very close to the 2020 target. 2) By how much would renewables plus nuclear have to displace coal to reach the target? Answer: The target could be reached if coal consumption were reduced by about 42 percent, and the displaced 9.2 quads of energy were replaced by renewables plus nuclear, implying more than doubling of renewable plus nuclear energy supply, to comprise 30 percent of all energy consumption. If renewables alone (i.e., non-nuclear) are to carry the weight of displacing coal, then they would have to increase their role in consumption by a factor of 4.7 over 2007 values. If growth in renewable energy supply is restricted to solar and wind only, then these sources would have to increase their role in consumption by a factor of 80 (that is, e-i-g-h-t-y). The reason for this big difference is that biomass and geothermal provided about 6.4 quads of energy in 2007, whereas wind and solar only 0.4 quads. The Obama Administration’s goal of doubling wind, solar, and biofuels production within 3 years may indeed be a worthwhile policy, but it is not consistent with a goal of displacing sufficient coal to reach the 14 percent 2020 target using wind and solar (and while biofuels have their own complexities as a policy issue, they are not really a substitute for coal in any case). 3) By how much would energy consumption have to be reduced to meet the target assuming no changes in the energy consumption mix? Answer: Energy consumption would have to be about 85.5 quads in 2020, about equal to 1992 values when the US economy was 35 percent smaller than in 2007. Some Comments on the Stress Tests First, number (1) above is really not desirable if the goal of mitigation policy is ultimately a reduction in emission of 80 percent or more. The reason for this is that while natural gas is less carbon intensive than goal, it is still carbon intensive. Locking in a large natural gas infrastructure is not compatible with large emissions reductions. Consider that in the hypothetical case that all US fossil fuel needs were to be met by natural gas, then 2007 carbon dioxide emission would have been 5,375 MMt, less than observed in 2007, but not consistent with any low stabilization target. Second, number (2) is theoretically promising but practically daunting. The following is worth repeating — for wind and solar to displace enough coal to reach the 14 percent target by 2020 would require that it increase by a factor of 80 in absolute terms from 2007 production. President Obama’s policy of a tripling in wind and solar energy supply in the next three years would leave a need for another increase by a factor of about 25 over the next 8 years if wind and solar are to displace sufficent coal to meet the target. Third, with respect to number (3), while there is a lot of potential to exploit in increasing energy efficiency, to reach the 14 percent would require a reduction of US energy use by about 2 quads per year for the next decade. Assuming that policy makers and citizens want economic growth to resume, this is a Herculean task. If you factor in that the EIA estimates to 2020 already include a good bit of efficiency gain in the BAU scenario, the task could be even larger if these assumed gains do not occur or if economic growth happens at a faster rate than assumed. In reality, of course, none of these “stress tests” would be applied alone; there would be a combination of all three approaches discussed above. However, I challenge readers to present a scenario combining decarbonization of the energy supply and efficiency gain that has a realistic chance of succeeding in meeting a 14 percent emissions reduction (below 2005) by 2020. I am not saying that it can’t be done, but I am saying that I don’t see how it can be done. The comments are open, have at it. Setting an emissions target and timetable, allocating emissions permits, and then saying that the magic of the market will efficiently take care of the task is exactly the answer I’d expect if one doesn’t have an answer. Markets can’t make the impossible possible, and when they are used in such a manner, often have undesirable results. The original article can be viewed here.
|
|
|
Back Home
Back to Top
|
 |
| Add a Comment: |
You must be a member to post comments. Please click here to sign up
|
| Article Comments: |
#2 is possible
Posted: 03/09/2009 04:54 PM by Zachary Moitoza
Since nuclear is a very low-carbon, baseload power source, it could demonstrably satisfy #2, although renewables alone couldn't. However, this is also unlikely, since many nations around the world are now planning more nuclear plants, and the U.S. is towards the back of the line on certain components not currently manufactured in the U.S. Still, if we embarked on an apollo or Manhattan level program, it could be done, but we would need to start right away.#1 and #3 can be quickly discounted based upon LNG imports (which are even more carbon-intensive) and Jevon's Paradox.
|
|
|
|
|
Corn and Coal: The Cornerstones of Obama...
By Robert Bryce
Feb. 5 2010, 5:47 EST
|
US Biodiesel: The Never-ending Subsidy S...
By Russ Finley
Feb. 3 2010, 4:17 EST
|
China And The “Deniers”: Why Climate Cha...
By Michael Economides, ET editor in chief, and Xina Xie, ET China correspondent
Feb. 2 2010, 11:41 EST
|
Obama’s “Clean Energy” Pandering: His St...
By Robert Bryce
Jan. 29 2010, 4:10 EST
|
Married to Mendacity: Growth Energy Cont...
By Robert Bryce
Jan. 27 2010, 4:27 EST
|
Chinese Coal Prices Soar, Power Producer...
By Xina Xie
Jan. 25 2010, 11:43 EST
|
White House Needs New Look At Energy
By Michael J. Economides, Editor-in-Chief
Jan. 22 2010, 12:49 EST
|
Bryce v. Pickens Tonight on Fox Business...
By Robert Bryce
Jan. 21 2010, 2:36 EST
|
America’s Future Auto Fleet: Electric Ca...
By G. Allen Brooks
Jan. 20 2010, 12:30 EST
|
2009 US Petroleum Trends
By Geoffrey Styles
Jan. 19 2010, 12:50 EST
|
Robert Bryce Talks With Author Mark West...
By Robert Bryce
Jan. 15 2010, 10:38 EST
|
China Pushes for Coal Gasification
By Xina Xie
Jan. 14 2010, 12:01 EST
|
|
|
|
US Coal Industry Balks at Proposal for H...
By Steel Guru
Feb. 8 2010, 12:59 EST
|
BP Shareholders Protest Canadian Oil San...
By Fred Pals
Feb. 8 2010, 12:51 EST
|
US Seeks Access to Nuclear Program of Pa...
By The News
Feb. 8 2010, 12:49 EST
|
Ukraine Says No Gas War with Russia
By RIA Novosti
Feb. 8 2010, 12:45 EST
|
Iran Discovers New Oil, Gas Fields
By Tehran Times
Feb. 8 2010, 12:25 EST
|
Arctic Sea Ice Vanishing Faster Than Mod...
By Bruce Owen
Feb. 8 2010, 12:16 EST
|
Fear and Farce of Climate Change Science
By Eric Reguly
Feb. 8 2010, 12:07 EST
|
Beyond the Black Stuff: Big Oil is Being...
The Economist
Feb. 5 2010, 11:37 EST
|
Energy Flow, Emergent Complexity, and Co...
By George Mobus
Feb. 5 2010, 11:27 EST
|
High Hopes for Clean Energy Jobs
By Rebecca Smith
Feb. 5 2010, 11:22 EST
|
Improved Lithium Ion Batteries
By Adam Frucci
Feb. 5 2010, 11:09 EST
|
Shell to Sell Oil Leases in Nigeria
By Elisha Bala Gbogbo
Feb. 5 2010, 11:02 EST
|
|
|
|
Home Owners in Barnett Shale Lease Dilem...
By Jack Smith
Feb. 8 2010, 12:19 EST
|
5 Dead in Gas Plant Explosion
By Michelle McLaughlin
Feb. 8 2010, 12:10 EST
|
Gas Sites Spur Air Worries
By Ben Casselman
Feb. 5 2010, 11:39 EST
|
Oil, Gas Output Rise in Colorado
By KRDO
Feb. 5 2010, 11:20 EST
|
Comparison of US Plans to Cap Carbon
By Timothy Gardner
Feb. 5 2010, 11:12 EST
|
Fed Doubts Energy States will Recover Fi...
By Stephen C. Fehr
Feb. 5 2010, 10:50 EST
|
Congress Ups Debt Limit, Then Votes to C...
By David Lightman
Feb. 5 2010, 10:41 EST
|
EPA’s New Biofuel Rules
By Geoffrey Styles
Feb. 4 2010, 4:40 EST
|
Obama Touts His Alternative Fuels Plan
By John Broder
Feb. 4 2010, 10:49 EST
|
Argentina Protests Over Oil Prospecting
By Sunday Morning Herald
Feb. 3 2010, 11:25 EST
|
Oil and Trucking Industries Challenge Ca...
By Dale Kasler
Feb. 3 2010, 11:12 EST
|
We Can’t Fight Two Wars at Once
By Alex Spillius
Feb. 3 2010, 10:50 EST
|
|
|
|
Italy’s Nuclear Plans At Risk
By Israel Rafalovich, ET Roving European Correspondent
Feb. 4 2010, 5:48 EST
|
U.K. Eyes Energy Reforms
By Selina Williams
Feb. 3 2010, 11:19 EST
|
BP Profits Slide on US Refineries
By Robin Pagnamenta
Feb. 3 2010, 11:03 EST
|
Jordan Wants Nuclear Power, Signs Agreem...
By Israel Rafalovich, ET Roving European Correspondent
Feb. 2 2010, 1:15 EST
|
Demand for Natural Gas to Rise
By The Peninsula
Feb. 2 2010, 11:27 EST
|
Gazprom to Extend Polish Contract on Eur...
By Tehran Times
Feb. 1 2010, 11:56 EST
|
BP Chief Hails American Breakthrough in ...
By Terry Macalister
Jan. 29 2010, 11:29 EST
|
Karzai: UK Troops Needed for 15 Years
By Ben Farmer
Jan. 28 2010, 10:56 EST
|
Science Chief Calls for Honesty on Clima...
By Ben Webster
Jan. 27 2010, 10:55 EST
|
European Offshore Wind Capacity up to 57...
By New Energy Focus
Jan. 19 2010, 10:41 EST
|
Preserve Coal Plants to Keep Lights On
By Tim Webb
Jan. 19 2010, 10:35 EST
|
France Cuts, Germany Debates Solar
By UPI
Jan. 15 2010, 11:14 EST
|
|
|
|
Russia, Venezuela Step Up Oil Cooperatio...
By Mu Xuequan
Feb. 1 2010, 11:28 EST
|
Belarus, Russia End Oil Supply Row
By Jacob Gronholt Pedersen
Jan. 28 2010, 11:12 EST
|
Gazprom to Increase Gas Supplies to Euro...
By RIA Novosti
Jan. 27 2010, 11:08 EST
|
BP Offers Technology, Expertise to Devel...
By RIA Novosti
Jan. 22 2010, 2:06 EST
|
Poland to Deploy U.S. Missiles Near Russ...
By Judy Dempsey
Jan. 22 2010, 12:46 EST
|
Ukraine Should Join Nord Stream Gas Proj...
By RIA Novosti
Jan. 19 2010, 10:50 EST
|
U.S. Dethroning Russia as Gas King
By Anatoly Medetsky
Jan. 14 2010, 10:57 EST
|
Turkey Approves Russian Gas Pipeline
By CCTV
Jan. 14 2010, 10:53 EST
|
Turkmenistan Resumes Gas Supplies to Ru...
By China View
Jan. 11 2010, 2:15 EST
|
Russia, Belarus End Oil Supply Talks Wit...
By China View
Jan. 11 2010, 2:11 EST
|
Venezuela, Russia May Develop More Orino...
By Jose Orozco
Jan. 4 2010, 10:46 EST
|
Russian Seaborne Crude Oil Exports Sched...
By Alexander Kwiatkowski
Dec. 30 2009, 10:59 EST
|
|
|
|
Gas Transfer to Europe Key in Turkey, Ir...
By Today’s Zaman
Feb. 8 2010, 12:55 EST
|
Iran, Pakistan to Ink Gas Deal in Turkey
By Tehran Times
Feb. 8 2010, 12:42 EST
|
Iraqi Officials Lament Failure To Refine...
By Radio Free Europe
Feb. 4 2010, 11:50 EST
|
Gas Transfer to Europe Key in Turkey, Ir...
By Today’s Zaman
Feb. 4 2010, 11:44 EST
|
Afghan Fight is Coming
By Rod Nordland
Feb. 4 2010, 11:18 EST
|
Oil Majors Move in on Iraq
By Oil Voice
Feb. 4 2010, 11:12 EST
|
Dubai Discovers New Oil Field
By Adam Schreck
Feb. 4 2010, 10:53 EST
|
Oil Demand Recovery Underway
By Trading Room
Feb. 2 2010, 11:25 EST
|
Saudis Want Taliban to Expel Bin Laden
By Abdullah Al Shihri
Feb. 2 2010, 11:01 EST
|
Iran Plans To End Energy Subsidies
By Andres Cala, European correspondent
Feb. 1 2010, 12:36 EST
|
Bulgaria and Turkey Agree on Natural Gas...
By Reuters
Feb. 1 2010, 11:54 EST
|
Lukoil to Develop Iraq Supergiant Oil Fi...
By Peoples Daily
Feb. 1 2010, 11:44 EST
|
|
|
|
China may Renew Record for Crude Oil Imp...
By China Post
Feb. 5 2010, 10:57 EST
|
China’s Oil Giants to Develop Iraq Oil F...
By People’s Daily
Jan. 28 2010, 11:21 EST
|
As China Rises, Conflict With West Rises...
By Katrin Benhold
Jan. 27 2010, 10:31 EST
|
China’s Oil Imports Continued Upward Cli...
Michael J. Economides, editor-in-chief, and Xina Xie, China editor
Jan. 26 2010, 10:41 EST
|
Sino-Kazak Pipeline Transports 20 mln to...
By Istock Analyst
Jan. 25 2010, 11:14 EST
|
China’s Economy is Soaring
By Zhou Xin and Chris Buckley
Jan. 21 2010, 10:53 EST
|
China’s US Purchases Up 300% in 2009
By Vincent Fernando
Jan. 19 2010, 10:16 EST
|
China Completes 1st Phase of Oil Reserve...
By China Daily
Jan. 18 2010, 10:57 EST
|
China Will Drive Future Car Demand
By NPR
Jan. 12 2010, 10:21 EST
|
Cold Snap Triggers Power Shortage in Chi...
By AFP
Jan. 11 2010, 2:36 EST
|
Oil Falls on Concern Investment May Slow...
By Ann Koh
Jan. 8 2010, 11:33 EST
|
Cold Snap Spurs Power Rationing in China
By Chris Buckley
Jan. 6 2010, 3:47 EST
|
|
|
|
Chevron Finds Natural Gas Off Australia
By Anna Driver
Jan. 27 2010, 11:11 EST
|
Another Gorgon Deal to Supply LNG
By ABC News
Jan. 8 2010, 11:42 EST
|
Australian $90 Billion Gas Megadeal with...
By Felicity Williams
Jan. 7 2010, 2:22 EST
|
Chevron Finds More Gas Off Western Austr...
By The Sunday Morning Herald
Dec. 15 2009, 10:32 EST
|
New Zealand on Verge of Oil Boom
By Oil Voice
Nov. 24 2009, 4:01 EST
|
Apache, Kuwait Join Chevron In Wheatston...
By Angel Gonzalez
Oct. 23 2009, 11:45 EST
|
Chevron Pushes Forward On Gorgon
By Geoffrey Styles
Sep. 21 2009, 10:08 EST
|
The Ghost Fleet of the Recession
By Simon Parry
Sep. 14 2009, 11:52 EST
|
Australian Parliament Rejects Carbon Tra...
By Reuters Staff
Aug. 13 2009, 10:43 EST
|
North Korea ''Test Fires Missiles''
By BBC Staff
Jul. 2 2009, 11:14 EST
|
North Koreans Condemn U.S. and Sanctions...
By CHOE SANG-HUN
Jun. 26 2009, 12:36 EST
|
Wind Turbines Killing Sleep Deprived Goa...
By Telegraph Staff
May. 22 2009, 11:08 EST
|
|
|
|
India Suggests Deregulating Gasoline, Di...
By Sunil Raghu
Feb. 3 2010, 11:23 EST
|
African Oil Fields on India Radar
By The Financial Express
Dec. 9 2009, 4:35 EST
|
Bangladesh to Revive Debate Over Myanmar...
By Pipelines International
Nov. 13 2009, 11:46 EST
|
RIL Discovers Oil in Cambay Basin
By Business Standard
Nov. 10 2009, 2:38 EST
|
India, Scotland Join Hands On Renewable ...
By EE Times India
Oct. 16 2009, 11:48 EST
|
Indian Subcontinent Weighs Nuclear
By Priyanka Bhardwaj and Michael J. Economides
Oct. 8 2009, 11:59 EST
|
Cameco Upbeat on Canada-India Nuclear De...
By Cameron French
Oct. 2 2009, 12:13 EST
|
Reliance Natural Seeks Dismissal of Gove...
By P.S. Patnaik and Gaurav Singh
Sep. 18 2009, 11:05 EST
|
Tangguh Plant To Ship Less LNG
By The Jarkata Post
Sep. 4 2009, 12:05 EST
|
Repsol Natural Gas Lot Production To Sta...
By Reuters
Aug. 28 2009, 11:52 EST
|
India’s Coal Needs Fuel Overseas Push
By Priyanka Bhardwaj
May. 28 2009, 4:25 EST
|
India Chooses Coal, Not Kyoto
By Priyanka Bhardwaj and Robert Bryce
May. 11 2009, 12:39 EST
|
|
|
|
India Draws Strategy in African Oil Asse...
By The Hindu
Feb. 8 2010, 12:40 EST
|
Nigerian Militants Claim Attack on Pipel...
By Seattle Times
Feb. 8 2010, 12:13 EST
|
Angola Oil Pipeline Attacked, by Swordfi...
By Matthew Clark
Feb. 4 2010, 12:29 EST
|
Nigeria’s Oil Pipeline Sabotaged
By BBC
Feb. 1 2010, 11:05 EST
|
Nigerian Militants Call off Oil Truce
By Scott Baldauf
Feb. 1 2010, 11:02 EST
|
Nigeria, UAE Supplies put OPEC Crude Pro...
By Iheanyi Nwachukwu
Jan. 27 2010, 11:05 EST
|
Nigeria Hopes to Fulfill Oil Contracts S...
By Reuters
Jan. 26 2010, 12:05 EST
|
Uganda to Block British Oil Bid
By AFP
Jan. 22 2010, 2:00 EST
|
Two Million Nigerian Vehicles to Run on ...
By Guardian Newspapers
Jan. 20 2010, 11:36 EST
|
Pirates Free Oil Tanker After Record Ran...
By Abdi Guled and Abdi Sheikh
Jan. 19 2010, 10:14 EST
|
Dana Gas Finds Oil in Egypt
By Ed Attwood
Jan. 12 2010, 10:45 EST
|
Sudan Seeks to Buy Natural Gas from Egyp...
By Sudan Tribune
Jan. 11 2010, 2:27 EST
|
|
|
|
Iran Plans 10 New Enrichment Plants
By Washington Post
Feb. 8 2010, 12:02 EST
|
Obama’s Nuclear Power Policy
By Mark Clayton
Feb. 5 2010, 11:16 EST
|
Iran Accepts West’s Nuclear Deal
By BBC
Feb. 3 2010, 11:09 EST
|
Iran Urges Islamic States to Possess Nuc...
By People’s Daily
Feb. 2 2010, 11:44 EST
|
US, Russia Near Deal on Nuclear Weapons
By Jonathan S. Landay
Feb. 2 2010, 11:06 EST
|
Italy Seeks Arab Role on Nuclear Row
By The International News
Jan. 26 2010, 12:21 EST
|
Russia Warns Against Rushing to Iran San...
By Reuters
Jan. 22 2010, 12:27 EST
|
U.S., Russia Never so Close on Iran Nucl...
By Mu Xuequan
Jan. 21 2010, 11:20 EST
|
India, Hungary Hold Talks on Civil Nucle...
By Sachin Parashar
Jan. 20 2010, 11:44 EST
|
Iran Rejects Nuclear Fuel Deal
By BBC
Jan. 20 2010, 11:09 EST
|
German Minister Tough in Nuclear Talks
By Reuters
Jan. 18 2010, 11:26 EST
|
Ahmadinejad Hails Iran’s Nuclear Progres...
By RIA Novosti
Jan. 15 2010, 11:24 EST
|
|
|
|
Bid to Develop Oil Sector in Libya Gathe...
Feb. 8 2010, 1:00 EST
|
Japanese firm to delay start of Egypt oi...
Feb. 8 2010, 1:00 EST
|
Wintry Weather Drives Energy Prices High...
Feb. 8 2010, 1:00 EST
|
Arab states may become solar energy expo...
Feb. 8 2010, 1:00 EST
|
US average gasoline price in four week s...
Feb. 8 2010, 1:00 EST
|
Indonesia considering slowdown in coal e...
Feb. 8 2010, 1:00 EST
|
China to increase LNG import
Feb. 8 2010, 1:00 EST
|
Cnooc Falls After Report of Possible Uga...
Feb. 8 2010, 1:00 EST
|
Climategate Scientist Considered Suicide
Feb. 8 2010, 1:00 EST
|
Biofuel Production Falls Far Short of Ta...
Feb. 5 2010, 1:00 EST
|
How Nigeria is sabotaging the global oil...
Feb. 5 2010, 1:00 EST
|
Europe Gasoline falls as economy concern...
Feb. 5 2010, 1:00 EST
|
|
|
|
|
|
|