Can I get some scientific articles about the carbon footprint comment? I would be interested in actual metrics and beliefs of the CO2 costs of the supercharger in comparison to a truck. I am 100 percent serious. Does anyone have comparison well to road of an electric car to a ICE? It would be nice if we had an archived article we can reference with 20 different independent articles by reputable institutions about this subject. So we can just copy the link to people for their own knowledge.
Unfortunately, the literature that I've seen is too old and unreliable to be used in the manner that people are likely to want it used. There have been a number of published estimates on lithium ion battery production, even several specifically on EVs. However, the nature of what those studies try to accomplish is general in nature and difficult to then apply to the specific case of Tesla and it's supplier. Commonly, Tesla critics reference two studies:
Argonne National Laboratory. A Review of Battery Life-Cycle Analysis: State of Knowledge and Critical Needs
http://www.transportation.anl.gov/pdfs/B/644.PDF
Hawkins, T. R., B. Singh, G. Majeau-Bettez, and A. H. Strømman. 2012. Comparative environmental life cycle assessment of conventional and electric vehicles. Journal of Industrial Ecology
Comparative Environmental Life Cycle Assessment of Conventional and Electric Vehicles - Hawkins - 2012 - Journal of Industrial Ecology - Wiley Online Library
Both have fatal flaws, as with any study, when used incorrectly. As one reads these two papers and try to tease out exactly what base assumptions they use and where they get their underlying data, it becomes very clear that these two papers (as with any paper of this kind) would have to make gross generalizations based on far outdated data.
For example, the Hawkins paper models the EV power train using a ABB ACS HXR355 motor:
ABB IE2 High Efficiency Cast Iron Motors - Process Performance Motors (IEC Low Voltage AC Motors)
Does that look like a Tesla Model S motor to you? They grabbed the environmental impact numbers from the 250kW version which only weighs 468 kg, or 1031 pounds. No wonder I'm looking at the chart on page 57 wondering how in the world they got the motor/engine values the put there. The other power train value is even worse - how they managed to get such an impact level on the inverter, charge controller, and motor controller is beyond me. Their paper is very vague about this part. But certainly, they are using industrial components for stationary applications and maybe they even added two motors together to get such high values.
The Hawkins paper uses the following paper for battery life cycle impact: Life Cycle Environmental Assessment of Lithium-Ion and Nickel Metal Hydride Batteries for Plug-In Hybrid and Battery Electric VehiclesMajeau-bettez, Guillaume ; Hawkins, Troy R. ; Strømman, Anders Hammer Environmental Science & Technology, 2011, Vol.45(12), pp.5454-5454
This one is behind a paywall - or get it through a library. In any case, this study looks at LFP and NCM lithium ion batteries - neither of which is used in the Model S. The total energy density was 112 and 88 Wh/kg, way off from the over 250 Wh/kg for NCR18650A (which is closer to the Model S chemistry). Interestingly enough, the study mentions that they are expecting 3,000 cycles for NCM and 6,000 for LFP. That's a lot of miles. Majeau-bettez paper estimates 22kg CO2/kg of NCM and LFP batteries based on re-mixing data from a paper by Rydh, "Energy analysis of batteries in photovoltaic systems. Part I: Performance and energy requirements" published in 2005. This value is very high. Much higher than the estimate given in the Rydh paper, much higher than some later papers
For instance, this much newer Argonne National Labs paper, Impact of recycling on cradle-to-gate energy consumption and greenhouse gas emissions of automotive lithium-ion batteries Dunn, Jennifer B ; Gaines, Linda ; Sullivan, John ; Wang, Michael Q Environmental science & technology, 2012, Vol.46(22), pp.12704-10
This one actually references the Majeau-bettez paper and notes that all the previous research is based on European production and use. Well, we know that is not the case for Tesla. The batteries are made by Panasonic in Japan (or China). Mr. Straubel says Japan, but we know that Panasonic made a new factory in China and stopped the expansion in Japan, so it isn't clear given the timelines whether current batteries come from Panasonic's China or Japan factories. In any case, the glider, the motor and many other of the big and heavy parts of the Model S is made in the U.S. There is 55% US+Canada content. Since the batteries come from Asia and are such a large and heavy component, that doesn't leave much more that isn't from US or Canada. Which means a lot of the GHG estimates based on European production and European power supplies is wrong. Further, since California has very little coal electricity production, the energy mix is actually much better than these papers suggest. Even in Japan, the coal production percentage is quite low (used to be a large percentage of nuclear, but obviously no more). In any case, the Dunn paper argues for a CO2 production level that is less than half of the Majeua-bettez paper, citing 10 MJ/kg as the "rough upper bound." Further, battery assembly is only 6% of the total energy in a cradle to grave scenario in this paper.
So after all of this… we basically are nowhere. Not really. It is likely that a Model S would take more greenhouse emissions to create due to the battery than a comparable internal combustion engine car, but there are enough factors thrown about all over the place that doesn't even necessarily make that true. Now in the use phase, using
Fuel Economy you can examine the impact of greenhouse gases on a daily basis. This requires your zip code because the impact varies depending on the electricity production in your specific case. I don't personally believe that solar at your house in a grid-tie arrangement truly lowers your greenhouse emissions for the Tesla Model S itself (it does in aggregate with your other activities), but the exact mix of natural gas, hydro, nuclear, and coal all significantly affect the resulting impact. Certainly for CA and New England, the greenhouse gas emissions are far lower in a Model S than any comparable internal combustion engine powered car.
Whew.
