TMC is an independent, primarily volunteer organization that relies on ad revenue to cover its operating costs. Please consider whitelisting TMC on your ad blocker or making a Paypal contribution here: paypal.me/SupportTMC

UoCS Study: How Green are Electric Cars?

Discussion in 'Energy, Environment, and Policy' started by johns258, Apr 13, 2012.

  1. johns258

    johns258 Model S Signature 998

    Joined:
    Feb 12, 2012
    Messages:
    23
    Location:
    Sanibel, FL
  2. JRP3

    JRP3 Hyperactive Member

    Joined:
    Aug 20, 2007
    Messages:
    10,113
    Location:
    Central New York
    Too bad they used data from 2007 since coal use has dropped since then.
     
  3. dhrivnak

    dhrivnak Active Member

    Joined:
    Jan 8, 2011
    Messages:
    2,150
    Location:
    NE Tennessee
    It has dropped and is below 44% coal. I did an analysis for the local city trying to get some Leaf's as part of a grant. I can share the spreadsheet if you wish but here is the summary.

    Dear Grant Committee;

    For this analysis I compared a 5 passenger Chevy Malibu to a 5 passenger Nissan Leaf which has similar interior volumes and vehicle weights.
    We assume both cars would have a similar life span and drive an equivalent amount of miles. They both have a 3 year 36,000 warranty with the Leaf having an additional 8 year warranty on the battery.

    According to the EPA the Malibu averages 26 mpg and also from the EPA the combustion of a gallon of gasoline results in 19.5 lbs of CO2. I also included an additional 2.6 lbs CO2/gal for the refining process of gasoline as crude oil must be refined before it can be used, whereas the electricity is in a form directly usable in a Leaf. So with a Malibu one gets an emission of .85 lbs-CO2 for every mile driven. See reverse side for calculation details and sources.

    For the Nissan Leaf the EPA says the Leaf uses .34KWh/mile. Kingsport uses power from AEP and their 2011 sustainability report states the company average 1.30 lbs CO2/KWh. Assuming an 85% charging efficiency this translates to an effective rate of .52 lbs-CO2/mile, a 39% reduction of CO2 over the Chevrolet Malibu base case.
    At 10,000 miles/year and an 8 year life this translates to a total reduction of (.35lbs/mile*10,000 miles* 8 years) 28,000 lbs-CO2 per car.

    If one takes into account the fact that the USA and AEP are reducing CO2 at a rate of 3% a year as they introduce more wind and solar that are CO2 free, and move to natural gas which is cleaner than coal, the numbers get even better for the all-electric Leaf showing an estimated 52% reduction by 2020.

    Sincerely

    David Hrivnak P.E. (Industrial Engineering)





    Supporting Data for Green House Gas Emissions


    Chevy Malibu - Base case
    26 Miles/Gal Fuel Economy of the 2010 Chevrolet Malibu
    0.75 lbs-CO2/mile using 19.6 lbs-CO2/gal
    0.85 lbs-CO2/mile Including refining detailed below

    Nissan Leaf
    340 W/mile - Leaf Fuel Economy of the 2012 Nissan Leaf
    85% Charging efficiency
    0.52 lbs-CO2/mile
    0.41 2020 estimated CO2 based on a 3% reduction/year
    31% Reduction
    39% Reduction with refining included
    52% Estimated reduction in 2020

    CO2 emissions for local power
    AEP Sustainability Report
    http://www.aepsustainability.com/docs/2011_AEP_CAReport.pdf

    Pg. 3 134,000,000 Tons/CO2 Reported in 2010
    268,000,000,000 lbs-CO2 Conversion (2000lbs/ton)
    Pg. 3 206,000,000,000 KWh Reported in 2010
    1.30 lbs-CO2/KWh AEP 2010 Average

    CO2 per gallon of gasoline burned
    http://www.epa.gov/otaq/climate/documents/420f11041.pdf
    8887 g CO2/Gal gasoline
    19.575 lbs-CO2/gal converted to lbs. with 454g/lb.


    Gasoline Refining
    Energy Information Agency report on CO2 emissions in U.S. Manufacturing
    http://www.eia.gov/oiaf/1605/ggrpt/pdf/industry_mecs.pdf

    Quantity of gasoline produced - EIA - Petroleum & Other LiquidsManufacturing Refining
    U.S. Refinery Utilization and Capacity

    Petroleum Refineries
    Pg. 6 277,600,000 Metric Tons CO2/year
    611,830,400,000 lbs. CO2/yr. Conversion (2204 lbs./MT)
    2006 15,600,000 US Refining capacity in barrels/day from website above
    42 gal/barrel (one could use the average of 30 gal/barrel of gasoline/diesel)
    239,148,000,000 Gal/year Convert to gal/year (*42*365)
    2.56 lbs. CO2/gal Additional CO2 generated in refining.
     
  4. drees

    drees Active Member

    Joined:
    Jun 23, 2009
    Messages:
    1,121
    Location:
    San Diego
    Yep, Nat Gas and Wind are up significantly to make up for coal drop.

    They also don't seem to account for upstream emissions.
     
  5. JRP3

    JRP3 Hyperactive Member

    Joined:
    Aug 20, 2007
    Messages:
    10,113
    Location:
    Central New York
    They claimed to use a well to wheels analysis.
     
  6. efusco

    efusco Moderator - Model S & X forums

    Joined:
    Mar 29, 2009
    Messages:
    4,590
    Location:
    Nixa, Missouri, United States
    And in 5 years, or 10 when coal is even lower as a source and/or when I can install my own PV and Wind array at my home I'll be able to plug into a Zero emissions system. Try that with your gas car. With an EV at least the potential for reduced emissions is there.
     
  7. zack

    zack Member

    Joined:
    Nov 15, 2010
    Messages:
    946
    Location:
    Minneapolis, MN
    Using government numbers, I've calculated that if coal is used to charge my Roadster, I cause 12 lbs of CO2 to be generated for each 20 miles of driving. Our coal-fired plant is right in town here in Minneapolis/St. Paul, so there's little transmission loss. A Porsche 911 Turbo, comparable in performance, gets 20 miles per gallon and each gallon produces 19 lbs of CO2. So if you really break it down, even using the dirtiest form of electrical generation, electrics still produce 63% of the CO2 that a comparable ICE produces. However, the greatest gain for our country is that we will eventually not need foreign oil as a result. And that means our military, which uses over half of our Treasury dollars, will stop sending our kids into danger overseas to fight for our energy, and will be able to drastically reduce budgets as a result. Which is a great thing for our economy. 8^D

    [I realize that there is a lot more to the equation... pumping, transporting, refining, transporting... and I'm sure my Roadster is in reality generating 50% or less of the CO2 that a turbo 911 has to ultimately generate, worst case.]
     
  8. DisneylandIsHome

    Joined:
    Jun 17, 2008
    Messages:
    66
    It appears that the Union of Concerned Scientists use well-to-wheels analysis on the EVs. Does anyone know if they used well-to-wheels analysis on the ICE cars?
     
  9. Doug_G

    Doug_G Lead Moderator

    Joined:
    Apr 2, 2010
    Messages:
    15,851
    Location:
    Ottawa, Canada
    That is my #1 peeve about these comparisons.
     
  10. vfx

    vfx Well-Known Member

    Joined:
    Aug 18, 2006
    Messages:
    14,792
    Location:
    CA CA
    It's my peeve too!

    We should start a club.
     
  11. Fredrik S

    Fredrik S Member

    Joined:
    Mar 24, 2012
    Messages:
    21
    Location:
    Stockholm, Sweden
    Were do I register as a member?
     
  12. Norbert

    Norbert TSLA will win

    Joined:
    Oct 12, 2009
    Messages:
    4,424
    Location:
    San Francisco, CA
    I thought this *is* the club.
     
  13. EV_de

    EV_de Model SP10/XP9 EU ZOE#47

    Joined:
    Jun 11, 2009
    Messages:
    415
    Location:
    Germany, IN
    most of us payed at least 5-30k $US initiation fee ..

    It must be 'the' club , otherwise we screwed ...
     
  14. JRP3

    JRP3 Hyperactive Member

    Joined:
    Aug 20, 2007
    Messages:
    10,113
    Location:
    Central New York
    I'd really be surprised if they did not apply the same criteria to ICE vehicles as EV's. This is not a report by Fox news or John Petersen after all.
     
  15. Teslawisher

    Teslawisher Member

    Joined:
    Jan 4, 2012
    Messages:
    320
    Location:
    Peoria, IL
    I don't recall where I read this, or how old this info is, but regards to using PV's to generate electricity to charge EV's, how much energy (coal or otherwise) is used to create the PV panels? I've read that it takes as much energy to create one than it can create over it's life. Is that right? If so, wind seems like a much better solution for a zero-emission system (even though enery is required to create the wind components).
     
  16. DuncanWatson

    DuncanWatson Member

    Joined:
    Apr 3, 2012
    Messages:
    284
    Location:
    Seattle, WA
    They provided some of the heuristics they used for EVs but completely neglected to tell us any of the methodology for ICE. Without that data we can't evaluate it. I consider this a worthless report at this time. Show me the data and let me know that transportation, refining and other costs are included for gasoline. I also want to see the proportion of tar sands production included as well as oil spill costs.
     
  17. AndreN

    AndreN Member

    Joined:
    Feb 22, 2012
    Messages:
    94
    Location:
    Redmond, WA
    You can actually refute that doing some simple logic. The cost of a thing can't be less than the cost of the energy used to make it (or the manufacturer wouldn't make a profit). If a 100w panel cost $300, it must have taken less than $300 worth of energy to make it (probably a lot less given materials/labor/profit but let's be conservative). Let's say you get 600w of electricity per day from the panel. That's 6 cents of electricity per day, or $21 per year. The panel would pay for the energy used to make it in 15 years, less than the 25 year warranty for the panel.
     
  18. drees

    drees Active Member

    Joined:
    Jun 23, 2009
    Messages:
    1,121
    Location:
    San Diego
    The EROI for a PV system is generally around 10:1 or so - meaning that over it's useful life it will generate about 10x more energy than used to build it.
     
  19. JRP3

    JRP3 Hyperactive Member

    Joined:
    Aug 20, 2007
    Messages:
    10,113
    Location:
    Central New York
    The full report, which should include their methodolgy, is supposed to be out today I think.
     
  20. Robert.Boston

    Robert.Boston Model S VIN P01536

    Joined:
    Oct 7, 2011
    Messages:
    7,842
    Location:
    Portland, Maine, USA
    Home installs of PV are fairly straightforward, as you're typically just putting panels on existing structures. Many people like living in bright sunny places, so they move to the resource.

    Home wind turbines, however, are likely to require extensive zoning. Furthermore, people tend to shun living in locations with a truly high-quality wind resource, unless you're along a beach, in which case the zoning issues will be huge.

    At grid scale, though, commercial wind is much further along than commercial solar. There are tremendous economies of scale in wind, while large-scale PV presents challenges.
     

Share This Page