Conventional Cars model-s-cherokee-1

Published on June 13th, 2013 | by Andrew Meggison

9

Tesla Model S Emissions Vs. A Jeep Grand Cherokee

model-s-cherokee-1Does the Tesla Model S pollute more than Jeep Grand Cherokee? Analyst Nathan Weiss on the financial website Seeking Alpha claims that yes, the Model S is worse than a big SUV. In response, Green Car Reports’ David Nolan, a driver of the Tesla Model S, took a closer look at Weiss’s methodology.

Weiss’ main argument is that while the Tesla Model S is indeed a fully electric vehicle and thus uses no gas, when looking at emissions, one must focus on more than what is coming out of the tail pipe. Weiss focuses on the power plants needed to charge the Tesla as well as charging inefficiencies that lead to energy loss – including so called “vampiric power loss” which is the power used by the Model S even when the EV is off. Additionally, the resources needed to manufacture the batteries to power the Model S should be included in total emissions as well, according to Weiss.

Upon the first publishing of the article in Seeking Alpha, Weiss came to the conclusion that a Tesla Model S has a real world CO2 emission of 547 gm/mi. This is indeed high. The V-6 Grand Cherokee’s official EPA CO2 number is 479 g/mi, while the more powerful V-8 model’s official EPA CO2 number 592 g/mi. So at first glance it seems that Weiss is correct.

However, Weiss later amended the article placing the Tesla Model S CO2 emissions at 346 g/mi, well below the Grand Cherokee.  The main reason for the reduction cited as a miscalculation concerning “vampiric loss”.

David Nolan came to a different conclusion. When Nolan did the research he came to a real world CO2 emission for the Tesla Model S of 292 g/mi. Nolan‘s calculation is much lower than Weiss’ first calculation, though not that much lower than Weiss’ amended calculation.

The authors differ mainly when it comes to the issue of “vampiric loss”. Nolan claims that Weiss’ understanding of the Model S battery thermal management system is incorrect. Weiss said in his article that energy was used to keep the Model S battery warm. This is incorrect according to Tesla. Thus, the “vampire loss” drops.

Additionally and perhaps more importantly, Nolan points out that the issue of vampiric power loss is only temporary. Tesla is working on a “sleep mode” for software improvements to reduce the dreaded vampire losses. The next major update that is due this summer is expected to cut vampire losses in half. By the end of the year, they will be virtually eliminated, according to Tesla spokesperson Shanna Hendricks reports Nolan.

In conclusion Nolan admits that the Model S is not perfect, and it does have comparable CO2 emissions as a Scion minicar. Perhaps more worrying to Nolan is Weiss’ calculation that power plant emissions give the Model S an effective level of NOx pollution about triple that of the EPA limit for gas cars and that effective Model S sulfur dioxide emissions equal that of about 400 gas cars. Nolan admits that he cannot refute those claims.

Yet there is hope on the horizon as America continues to embrace cleaner and cleaner alternative fuels. It is no longer a question of if America can green its entire power grid, but rather a matter of when. And one day, you may be able to drive your next-generation Tesla Model S guilt and emissions free.

Source: Seeking Alpha | Green Car Reports

Andrew Meggison was born in the state of Maine and educated in Massachusetts. Andrew earned a Bachelor’s Degree in Government and International Relations from Clark University and a Master’s Degree in Political Science from Northeastern University. Being an Eagle Scout, Andrew has a passion for all things environmental. In his free time Andrew enjoys writing, exploring the great outdoors, a good film, and a creative cocktail. You can follow Andrew on Twitter @AndrewMeggison 



MAKE SOLAR WORK FOR YOU!





Next, use your Solar Report to get the best quote!

Tags: , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , ,


About the Author

Andrew Meggison was born in the state of Maine and educated in Massachusetts. Andrew earned a Bachelor's Degree in Government and International Relations from Clark University and a Master's Degree in Political Science from Northeastern University. In his free time Andrew enjoys writing, exploring the great outdoors, a good film, and a creative cocktail. You can follow Andrew on Twitter @AndrewMeggison



  • Nima

    this whole comparison is flawed.
    1. Tesla and Jeep and GM and the rest of the car manufacturer’s make cars not power plants and so to blame them on the source of energy pollution is mere hyperbole.
    2. electricity is not a source fuel its an intermittant form of energy, how that electricity comes to be is a matter entirely based on the region you live in and the source of electricity you happen to have. In Germany the EV from Tesla would run virtually pollutant free.
    3. Even if somehow it made any sense to blame car manufacturers on the source of fuel, then just as the tesla is suppose to take in account power plant pollutants, then so does every gas car have to account for not just tail pipe emissions but also, refinement process pollutants, mining pollutants, Transportation of fuel pollutants and that’s not even mentioning the environmental calamity when things go wrong, like oil spills from tankers, and from oil rigs and drilling operations.

    4. And this is the most important point. If a tesla owner really really cared and wanted to drive pollutant free, they can install solar panels on their roof and drive with the sun, while the cost is extra the OPTION is there, while the Jeep simply does not give you that option.

    This whole point of “you’re not really making a difference with electric mobility, because of power plants” is as ridiculous as saying we shouldn’t use the internet cause its not as factually correct as a book, IT DEPENDS ON THE AUTHOR! Internet is just a medium!

    • Jo Borras

      Stop using logic and sound thinking on the internet! Nobody wants that!! :)

  • Markwbrooks

    The short sellers BS is totally incorrect and fundamentally
    impossible.The EPA score reflects a vehicle’s tailpipe greenhouse gas emissions ONLY.

    It does not include a vehicles full fuel lifecycle CO2 estimates. It does not consider all steps in the creation and consumption of the vehicle fuel, from production and refining to distribution. It only includes the CO2 from final use.

    Since the TESLA Model S can go father on the energy
    used to create a gallon of gasoline, than the Jeep can on the gasoline, It is physically impossible for the TESLA to emit more CO2 than the Jeep.

    For gasoline from heavy oil sources ( now 20% of US gasoline sources) the real CO2 footprint of the Jeep becomes obscene ( 3 times what the EPA lists). For some real facts, and not just TESLA short sellers wishful thinking google:

    The Oil Sands’ Surprising New Nemesis: Plug-in Vehicles

    • Markwbrooks

      Oh, and I would also Like to point out, that as a seeking Alpha member myself, that the author is a well know Tesla Short seller, has posted multiple rather outrageous blog offerings like this one attacking TESLA specifically for obvious monetary gain. As posters on seeking alpha often do, he simply deletes any comments that are not : ” engaging in dialogue”. Any attempt by multiple authors to point out his outrageous errors gets deleted, sometimes within minutes. only those “soft selling” alternate views remain.
      Do not give this man or his investment firm any air time, as he will not return the favor.

  • UncleB

    Power from the Chinese Thorium LFTR styled reactors will clear the air in China – replace coal, oil, in furnaces there, and is safer by far than enriched uranium systems. China after all and the Communist politburo group of seven have decided to mandate electric transportation for that country. U.S.A. a mere 300 MM souls hardly matter to Asia or Pan Eurasia – they will follow China to electric three moving part drives and Solar, Wind Wave, Hydro, Tidal, Geothermal, Biological and Thorium created electricity. Massive policy change in the world, America a moot point.

  • Dave Crawford

    This is ridiculous and comparing apples to oranges. If he’s going to do a lifecycle pollution analysis for the Model S..you have to do one for the Jeep as well and take into account all the pollution that comes from getting the oil out of the ground, refining it, flying/trucking it half way around the world..not to mention the energy and pollution needed to manufacture and maintain an ICE engine. This article compare WORST case for Model S agains BEST case for a Jeep. Fundamentally flawed and ignorant analysis..or more likely pushing an agenda…unfortunate. Why can’t people get behind a new AMERICAN car company that is leading the industry in innovation and customer service?

    • t_

      So, even the worst case for the Tesla is far better than the Cheroke.

      And as everyone else said, there are nuclear, hydro, wind, solar options for making electricity and almost no CO2 emissions. And maybe, we’ll have far more cleaner sources of electricity soon.

  • Jonny_K

    Deja vu all over again. There was a similar hit piece years ago claiming a Hummer was greener than a Prius. That piece got picked up trotted around all over the place. It was completely bogus. IIRC, a Toyota executive took the trouble to rebut it.

    This is beginning to be a genre. Does it have a name?

  • Pingback: Cleantechnica Takes on the Myth that Electric Cars Aren't That Green()

Back to Top ↑