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MODEL S: What's the truth about the carbon footprint?
- Thread starter Bluhorizan
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- Energy Environment Policy
Install a solar array on your house that produces more energy then it puts into your Model S and you can effectively ignore all the stuff people say about you actually generating more carbon than you use since, your car runs on nothing but sunlight from that point forward.
Sigh. Again. Once someone writes a bogus story with false data (JPMORGAN), then everyone else starts referencing it and giving Tesla a bad name. http://www.econmatters.com/2013/05/how-green-is-tesla.html . Somebody needs to write an article about how JPMORGAN's data is bad.
Problem #1:
The gasoline car calculation only includes tailpipe emissions, not upstream emissions.
To calculate total energy, either the MPG is wrong or the GJ of energy per gallon is wrong.
FuelEconomy.gov shows upstream energy usage to be about 20% of total usage, or 25% of tailpipe usage, so the Civic hybrid emits about 252 g/mile or 46.6 GJ of fossil fuel per year.
Problem #2:
The Tesla equation is using real life efficiency numbers while the Honda equation is using EPA rating numbers. Perhaps the EPA was pessimistic when rating the Honda and optimistic when rating the Tesla, but absent any proof of this, shouldn't we use the same standards for both (either fleet average or EPA rating)? Since fleet average of the Honda is hard to find, I suggest we use EPA rating for both. This improves the Tesla efficiency to .205 kWh per km and reduces Tesla to closer to 41 GJ of fossil fuel per year, less than the Honda Civic hybrid.
If every car had a smaller carbon footprint than a Honda Civic hybrid, we'd be far better off than we are today.
Problem #3:
They assumed a nationwide electric mix, but Tesla has sold half of their cars in California where the grid emits 50% of the CO2 per kWh that the nation's average does. A California Tesla emits less than half the carbon that a Civic hybrid does, and a Washington state Tesla emits half the carbon of a California Tesla. Given the high sales of Tesla to CA and WA, knocking 25% off of emissions compared to the nationwide average seems conservative, which brings Model S toward 31 GJ of fossil fuel per year.
There are other things to nitpick, like choosing a relatively low value of miles per year makes the vampire range proportionally worse, but the bottom line is that for most owners, Model S burns fewer fossil fuels and emits less CO2 than if the owner had bought a Civic hybrid.
Since most of us owners probably had a higher polluting car than a Civic hybrid as our 2nd choice (mine was the 20 tailpipe mpg Audi S6), Model S lowers the nation's carbon footprint.
I'd further add that comparing a large luxury sedan to an econobox is hardly reasonable on the face of it. I speculate that very few Model S customers would have purchased a Civic (or similar) instead. If the study had compared the Model S to the US fleet average, even of new cars sold in 2012, it would have been a better comparison and once again showed that the Model S reduces emissions.
Another point is that CO2 isn't the only thing that matters, and the location of some pollutants matters a lot. Incomplete burn of gasoline releases volatile organics and particulates, both of which contribute to smog and other local pollution issues. The Civic dumps most of its pollution directly into heavily populated places, while power plants are generally located in lightly populated areas or, at a minimum, have tall stacks to disperse pollutants so as to minimally affect local populations.
Another point is that CO2 isn't the only thing that matters, and the location of some pollutants matters a lot. Incomplete burn of gasoline releases volatile organics and particulates, both of which contribute to smog and other local pollution issues. The Civic dumps most of its pollution directly into heavily populated places, while power plants are generally located in lightly populated areas or, at a minimum, have tall stacks to disperse pollutants so as to minimally affect local populations.
If these "news" outlets have a problem with Tesla selling Model S in the U.S., fine. Keep driving the Civics. Send the Model S cars over here. Gas is $8 the gallon, and the German grid is 25% from renewable sources on national average in 2012. Can't wait for August to come.
Exactly. ICE have more parts in the engine block in addition to the radiator, muffler, gas tank, and require more maintenance trips to the garage to change the oil, filters, spark plugs, inspect fuel lines,etc). Plus an electric cable can probably last a century, but the trucks that carry the gas to the gas station spewing ICE exhaust as they plow the roads not only cost gas, but relatively frequent maintenance to, changing 18 tires, brake pads, engine oil and filters, and eventually need to be completely replaced with another new truck with its ICE, parts etc.
RichardC
Cdn Sig & Solar Supporter
There is a lot of disinformation being published about battery packs and the energy used in manufacturing, etc. all of which is a rounding error when compared to the life cycle carbon emissions resulting from the fossil fuel consumption of an ICE vehicle. The key issue is the source of the electricity used by the Model S. In much of Canada most electricity is produced from low carbon sources, principally hydro, but significant nuclear (mostly in Ontario), and growing amounts of wind and other renewables. Purchasing green energy from a supplier such as Bullfrog Power and putting up you own solar panel array (we have done both) is a complete answer to any concerns about the carbon footprint of the Model S.
From a policy perspective, a substantial and predictably increasing carbon tax would automatically facilitate the transition to low carbon sources of electricity and continuously increase the relative advantage (from a GHG emissions perspective) of electric cars relative to ICE vehicles.
From a policy perspective, a substantial and predictably increasing carbon tax would automatically facilitate the transition to low carbon sources of electricity and continuously increase the relative advantage (from a GHG emissions perspective) of electric cars relative to ICE vehicles.
dhrivnak
Active Member
As with any analysis the assumptions are a big part of the findings. As a licensed Professional Engineer I have been involved in a few grants locally to compare energy consumption. If one compares a 2013 BMW 750Li xDrive to a 2013 Model S using EPA numbers the Model S shows a nice 58% reduction in CO2 using American Electric Power, far from the greenest utility in the USA. If one assumes the gasoline must be at least refined the improvement jumps to a 64% reduction in CO2. True if one compares a Model S to a Prius then there is only a modest 12% reduction, again if you assume one must at least refine the gasoline. If you pay for "green" power or make your own solar the reduction is even more.
I think it is more than fair to include at least refining as the KWH sold from AEP is delivered straight to my house in a usable form. Raw crude would really gum up a modern engine, especially if it were tar sands oil.
As a side note on EV's the EPA measures wall to wheel in their calculations so charging efficiency is part of their watts/mile calculation.
Feel free to look at the details in the spreadsheet at my public drop box account. See the Model S tab. A free lunch to anyone who finds an error.
https://dl.dropboxusercontent.com/u/94320747/GAS_VS_Electric.xlsx
I think it is more than fair to include at least refining as the KWH sold from AEP is delivered straight to my house in a usable form. Raw crude would really gum up a modern engine, especially if it were tar sands oil.
As a side note on EV's the EPA measures wall to wheel in their calculations so charging efficiency is part of their watts/mile calculation.
Feel free to look at the details in the spreadsheet at my public drop box account. See the Model S tab. A free lunch to anyone who finds an error.
https://dl.dropboxusercontent.com/u/94320747/GAS_VS_Electric.xlsx
RichardC
Cdn Sig & Solar Supporter
A Telsa is Expected to get Greener Over Time
A further, critically important, consideration is the fact that there is zero possibility of any meaningful reduction in the carbon footprint of the ICE vehicle (biofuels being of limited availability and having a substantial carbon footprint) while the Tesla can and will become greener as more and more renewable energy is added to the grid. Trends such as the rapidly falling price of solar panels, the growth in wind, geothermal, small nuclear reactors, etc. can all be expected to reduce the carbon footprint of the Tesla over time. See: http://cleantechnica.com/2013/03/17/bjorn-lomborg-dirty-little-mistakes/#r9vPZU6saXdU56kW.99
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int32_t
Tesla Spotter
I can squash this one. I don't know about energy required to make batteries so I won't weigh in there, but I imagine it's not as much of an impact as burning fuel to get anywhere (and burning fuel to not get anywhere, in the case of idling).
We've kept records for the past 13 years for my family's 2003 Honda Accord's fuel usage. Lifetime average fuel economy is 7.02 L/100 km or 625 Wh/km equivalent. A year ago I took those paper records and typed them into a spreadsheet. A couple days later I emerged, bleary-eyed, with some interesting numbers.
Here in Alberta almost all our electricity comes from coal. I even accounted for the type of coal we use in these carbon calculations. Essentially this is a worst-case dirty-as-it-gets view, and adding renewables (wind and solar) to the mix will improve matters to the point where carbon emissions are entirely neutral.
The number show that the coal-powered Model S produces 2/3 of the carbon emissions of our Honda. Things to note:
- The Model S is a bigger, heavier (and faster) car than our Accord. A Model 3 would blow our car away completely in terms of carbon emissions and would be a more fair comparison.
- These numbers, unlike our friends at wattsupwiththat with their Jeep, are accounting where the gas comes from, too. There's a significant amount of electricity invested in the gasoline refinement process. You can't account for battery manufacturing and then start with gas in the tank when comparing carbon emissions! (Pet peeve.)
- As I said before, I am not accounting for any battery production. I am also not accounting for the manufacturing of the engine, fuel tank, catalytic converter, and the other ICE-related crap they have to use to make fires turn wheels in the Jeep.
You can install solar and "offset" your Jeep carbon but the Jeep will still be making carbon ...
Full article at:
Anthony Watts - SourceWatch
Full article at:
Anthony Watts
Climate misinformer: Anthony Watts
Anthony Watts - RationalWiki
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int32_t
Tesla Spotter
int32_t
Tesla Spotter
Evidently a small but very loud (and somewhat obnoxious) group. It's more fun to be "for" the EV movement than "against" it ... because there is only one side that's going to win. Oil will not last forever, and in my opinion, should be preserved for its valuable plastic- and lube- making properties.
reynirb
Member
Didn't see anyone bring up the study from the Union of concerned Scientists that studied the issue in 2015.
Cleaner Cars from Cradle to Grave (2015)
http://www.ucsusa.org/clean-vehicles/electric-vehicles/life-cycle-ev-emissions#.WBWXXskbjwD
According to the study, they pretty much concluded that "By the end of their lives, gas-powered cars spew out almost twice as much global warming pollution than the equivalent electric car. Disposing of both types of vehicles (excluding reusing or recycling their batteries) produces less than a ton each."
They have an actual chart that shows the emissions based on what state you live in. My section of Florida does not use coal, the power generated in my region is all solar, nuclear or natural gas.
Unfortunately, my statewide emissions average isn't as good as CA, as they lump us with Crystal River and the outdated power plants further north in the state that are on the list of 20 most polluting plants in the country...
Cleaner Cars from Cradle to Grave (2015)
http://www.ucsusa.org/clean-vehicles/electric-vehicles/life-cycle-ev-emissions#.WBWXXskbjwD
According to the study, they pretty much concluded that "By the end of their lives, gas-powered cars spew out almost twice as much global warming pollution than the equivalent electric car. Disposing of both types of vehicles (excluding reusing or recycling their batteries) produces less than a ton each."
They have an actual chart that shows the emissions based on what state you live in. My section of Florida does not use coal, the power generated in my region is all solar, nuclear or natural gas.
Unfortunately, my statewide emissions average isn't as good as CA, as they lump us with Crystal River and the outdated power plants further north in the state that are on the list of 20 most polluting plants in the country...
AntronX
Member
I think it's safe to assume that we in south-east FL get about 50% night time off-peak (1am-5am) power from our 2 nearby nukes, giving our EVs close to 100 MPG CO2 equivalent compared to gas cars. And don't feel too bad about Crystal River coal plant, it only contributes about 5% of state's total electricity.
reynirb
Member
Well, problem is the Super polluters kind of offset a lot of the clean energy in the state.
Home - Super Polluters
And since FPL offers pretty crappy off peak plans, and despite a lot of talk, offer no EV incentives, most people just charge at peak times.
FPL just had another record monopoly profit, so they don't really appear to give a rats behind.
AntronX
Member
I only focus on CO2 emissions. Florida has very clean power grid thanks to ~70% of power coming from natural gas. It is very close to California's CO2 per kWh intensity while being 1.5 - 2 times cheaper on average. FPL does offer nice TOU plan, where you would pay 6 cents per kWh 9pm-12pm and about 21 cents 12pm - 9pm in the summer, and 6 cents on the weekends. But because air conditioning runs pretty much continuously during daytime, it ends up costing more in the end. It may work if both spouses work during daytime, commute in 2 EV's at least 50 miles a day and keep air con turned off when away from the house.
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