electric cars and CO2


In the randform post about electric vehicles it was stated that electric cars are – apart from the exhaustion – not green if they don’t use renewable energies. It is however an interesting question wether they are at least a bit greener than conventional cars. The answer to this questions depends of course on what is meant by green and which cars and methods of electricity generation you are taking into account. When looking into the issue, I stumbled upon a computation by Dan Rabinowitz at homocombustans. According to an article of AP with the title: Israel focuses its energy on clean technologies there might be soon quite a lot of electric cars in Israel:

Israeli-American businessman Shai Agassi, of Project Better Place, said Israel’s small size and dense population, along with government help, made the country attractive for his firm’s network for encouraging electric cars.

He predicts that about half the cars in Israel will be electric by 2015.

Dan Rabinowitz thus computed the expected CO2 emission due to the use of an electric car as proposed by Better Place to the expected CO2 emission of a normal gasoline car.
His computation goes as follows:
According to him there are about 75% coal plants, 25% gas plants for electricity generation in Israel, he considers the renewable energy part negligable.

According to Wikipedia (without source or citation) one kwh (kilowatt hour) of electricity made with coal produces 1.47 kilogram of CO2. Rabinowitz used that number. For natural gas he uses the number
0.57 kg CO2 per kwh. (In the footnote *1) there are some other estimations for CO2 output.)

So 2700 kwh would produce 3.36 tons of CO2
[(0.75*1.47 + 0.25*0.57)*2700 = 1.245 * 2700 =3361]

According to the website at better place:

a 24 kWh lithium-ion battery (about 200 kg/440 lbs) in a competitively priced medium-sized sedan provides a range of about 160 kilometers (100 miles) on a single charge.

That is if you drive on average 18 000 kms per year then you would spend an energy of
[18000/160*24= 2700], which would produce as above computed 3.36 tons of CO2.

According to Rabinowitz this website says that a normal Renault Megane type 3 emits on average 130 grams of CO2 for every kilometre travelled. That gives 2.34 tons of CO2 [18000*0.130= 2.340 ]

Thus according to this computation an electric car fueled with electricity from the above mix of coal and gas plants produces MORE CO2 than a regular car!

As indicated in the footnote the CO2 output per kwh is a debateable factor. Lets thus see what factor you would need to have an equal output of CO2 than the Megane type 3:
2340/2700=0.87

Hence if for example if all electricity production in Israel would be from natural gas then an electric car would produce a little less CO2 than the Megane.

This gives an interesting side aspect to the Israel – Lebanon – gas – conflict as described in the article:
UN stays out of Israel-Lebanon gas dispute!

However given the very good conditions for solar energy in Israel the big question is of course why solar energy is not more pushed forward.

Footnote:
*1)According to the US report Carbon Dioxide Emissions from the Generation of Electric Power in the United States
page 3

The national average output rate for coal-fired electricity generation was 2.095 pounds CO2 per kilowatthour in 1999

page 5

The output rate for CO2 from natural gasfiredplants in 1999 was 1.321 pounds CO2 per kilowatthour.

1 pound = 0.45359237 kilograms so one has 0.95 kg CO2 per kwh for coal and 0.6 kg CO2 per kwh for natural gas according to this report.

This is more or less in accordance with numbers given in table 2 of the german study CO2-Emissionen der Stromerzeugung by Wagner, Koch and Burkhardt from the University of Bochum.

Concerning the energy mix in Israel: According to Israels major electricity company the IEC there is a power of 11.664 MW produced by fossil fuels with an energy mix which is about the one given by Rabinowitz. I couldnt find much on the installed solar energy but already judging by the AP article it seems too be much less than 11.664 MW.

5 Responses to “electric cars and CO2”

  1. Gertruda Hinteregger Says:

    Sehr geehrte Blogschreiber

    Ich verstehe Englisch, möchte aber gerne von Ihrer angebotenen Übersetzungsmodalität Gebrauch machen, da ich hiermit Missverstände vermeiden möchte.

    Ihr Blogpost von vor zehn Jahren ist nun ein bisschen in die Jahre gekommen und vielleicht haben sich auch bei Ihnen neue Erkenntnisse zum Thema Elektromobilität ergeben. Vielleicht kann ja auch ein Interview mit Hildegard Wortmann, Vorständin bei Audi, Ihre ursprünglich Vorbehalte gegen Elektromobilität auflösen. In dem Interview, dass ich ihnen gerne zu Herzen legen möchte, sagt Frau Wortmann unter anderem:

    Als ich vor zwei Jahren zu Audi kam, rieten mir nicht wenige, den Markenclaim zu verändern. Aber auch nach 50 Jahren ist “Vorsprung durch Technik” relevanter denn je.

    ….

    Durch meine langjährige Tätigkeit in der Automobilindustrie hatte ich einen sehr guten Einblick davon, welche Wirksamkeit Elektromobilität zur Reduzierung von CO2-Emissionen hat. Die Faktenlage zeigt: Die Zukunft ist elektrisch. Alle anderen Alternativen werden diesen Beitrag nicht in der Wirksamkeit und Effizienz leisten können.

    …..

    In den nächsten Jahren stellen wir komplett auf Elektroautos um. 2025 wird die Produktion für unser letztes neues Verbrenner-Modell starten. Alle weiteren Audi-Modelle ab 2026 fahren rein elektrisch. Schon jetzt sind viele unserer Werke CO2-neutral, bis 2025 sollen es alle sein. Dabei geht es darum, das Werk mit regenerativen Energien zu betreiben oder auch das Entsorgungssystem und Werkstoffe auf nachhaltige Alternativen umzustellen. Der Audi e-tron, den wir seit 2018 in Brüssel produzieren, ist in einem komplett CO2-freien Werk produziert und wird bilanziell CO2-neutral den Handelsbetrieben übergeben.

  2. nad Says:

    @Gertruda Hinteregger

    I regard your comment not as an attempt of intelligent spamming and will try to answer it later. But first a translation of your comment without guarantee:

    ——————————————————————————————————–
    Dear Bloggers

    I understand english but I would like to make use of your translation service in order to avoid misunderstandings.

    Your ten year old blogpost has now aged a bit and thus you may have gained new insights into the area of elektromobility.
    Maybe an interview with Hildegard Wortmann, Vorständin at the company Audi, may resolve your objections against electromobility. In the Interview, to which I would call your attention, Mrs. Wortmann says among others:

    When I came to Audi two years ago, not too few people suggested to change the brand slogan “Vorsprung durch Technik” (“advantage through technology”). But even after 50 years, it can be said that “Vorsprung durch Technik” is more relevant than ever.

    ….

    Due to my longtime engagements in the car industry I gained a very good insight into the efficacy of electromobility with regard to the reduction of CO2 emissions. The Facts show clearly: The future is electric. All other alternatives won’t contribute with such an efficacy and efficiency.

    ….

    In the next years we will completely restructure towards electric cars. In 2025 production of our last combustor car will start. All other Audi cars will be electric starting from 2026 on. Many of our factories are, already now, CO2 neutral – until 2025 all of them shall be.
    This encompasses factories running with regeneratives energies or changeing disposal systems or basic materials with regard to sustainable alternatives. Audi’s “e-tron”, which we produce in Brussels, is produced in a completely CO2-free factory and thus transfered financially to commerce, as CO2 neutral.

  3. Gertruda Hinteregger Says:

    Thank you very much for your fast translation. Please have a look at video about Audi at vogue.de. It is also on youtube:
    https://www.youtube.com/watch?v=sS6NbNWOB2Q

    Looking forward to your comment.

  4. nad Says:

    “Maybe an interview with Hildegard Wortmann, Vorständin at the company Audi, may resolve your objections against electromobility. ”

    I don’t have objections against electromobility per se, but often enough something against how certain forms of electromobility are implemented.
    Like for example I have very strong objections against the Berlin Tesla Gigafactory, with all its chemicals right next to one of Berlin’s major drinking water supply lines (river Spree) and on top in an area which grapples with water scarcity.

    Regarding the Tesla factory’s main model -I have strong doubts about the Model Y itself (this seems to hold also for the Audi). That is due to the current battery technology – it seems that currently electromobility is more useful for planable mobility, like within a logistical network, than like for weekend (shopping) tours, but overall this is another topic to be discussed elsewhere. Just a quick citation from renault which basically speaks for itself:

    However, leaving the battery fully charged for an extended period of time is not recommended. In fact, it could actually accelerate the wear on battery cells. The best option is to charge your battery to no more than 50% before leaving your car parked for an extended period of time.
    That said, it is best not to leave the battery completely empty either, so that it can regularly recharge the small 12V battery that powers the car’s various accessories. With Renault ZOE, we recommend a minimum charge of 20%. This way, the car will be ready to drive right away, without needing to be charged first.
    ….
    If there is one thing lithium ion batteries don’t like, it’s hot weather. In extreme cases, when the temperature exceeds 40 degrees, there is a small but irreversible loss of the battery’s total capacity. This decrease in capacity is relatively insignificant, however. It is primarily the cycles of charging and discharging that wear out the batteries.

    Apart from that I am really concerned about the speed with which electromobility is now pushed, especially in Europe. I don’t see that the electricity grid and the overall power infrastructure in Europe is prepared for that. I fear since long that electromobility will be/ is taken worldwide as a pretext for pushing more nuclear fission energy and this seems to happen also in the EU, where it is currently discussed to declare commercial fission power production as “environmentally sustainable economic activity”. Nuclear.org writes:

    The proposed CDA elevates three distinct nuclear energy activities into the taxonomy: demonstration units for advanced nuclear technologies; the construction of new nuclear power plants using best available technologies; and electricity generation from existing nuclear installations.

    As I explained before the actinides can -with current technology- only be “efficiently” transmuted into something less radioactive with fast neutrons, i.e. in particular with fast breeders – a sofar not very successful (mildly speaking) and dangerous technology. With all other reactor types there will be a lot of nuclear waste. Moreover with (fast) breeders you can breed new fission material, which promotes a new plutonium/uranium market and hence even more waste. The current “waste problem CO2” might look in retrospective small against this new type of waste problem.
    Caring about a “halfway safe” decomissioning of old nuclear power plants might be discussed as an “environmentally sustainable economic activity”.

    I would like to mention in this context that I currently have not so much problems with the gas regulations of the EU draft. But then I haven’t read the details. In particular the informed randform reader knows that I am rather concerned about methane. And it could be the case that “gas discharges from clathrates and permafrost might be so destructive that it would be better to burn them (which produces less potent CO2).”
    It should also be pointed out that biogas is often from a “renewable source” (like from decaying wood, or as wood gas).

    In the context of the above post and of electric cars it should be repeated that is usually more efficient to burn gas and use that energy than to burn it, transform it into electrical energy and then use it (like via electrical energy from gas power plants). So if one uses gas for mobility then gas fueled cars seem to be more environmentally friendly than electrical cars, at least energy wise (I don’t know about potential CO2 capture technologies).

    Concerning Audi in particular- I think it is good if companies at least try to care about the environment, but some remarks to what is written on the audibrussels website (via co2-neutral-label)

    Since 2012, we have been using exclusively renewable energy from hydro power to meet our energy needs. Since 2013, the power supply has also been supplemented with an additional form of renewable energy: our plant roofs boast the largest solar panel installation in the Brussels Region, covering an area of no less than 107,000 m², of which 20,000 m² were newly installed in 2020. This facility will generate more than 8,000 MWh of electricity annually, which corresponds to the consumption of approximately 2,300 average Belgian families.

    In the first Tesla environmental report (erster UVP report) it was written:

    Es ist geplant 16.000 Nm³/h Erdgas einzusetzen,…Es ist geplant elektrische Energie mit einer Leistung von 109 MW einzusetzen..

    (it is planned to use up 16.000 Nm³/h of natural gas for ovens etc. and 109 MW of electrical energy for production etc.)

    Audi uses eventually less, because it is maybe not a “gigafactory” but let’s assume it does. Then

    1 Nm³ gas corresponds roughly to 10 kWh (see e.g. here), so the gas encompasses roughly a power of 16.000 Nm³/h ~ 160 000 kW = 160 MW. I.e. by that computation the car giga factory needs 269 MW power.

    The solar electricity that powers “approximately 2,300 average Belgian families” corresponds to:

    8,000 MWh / 365*24h = 0,91 MW

    So you would need roughly 250 Audi factory roofs to cover the energy needs of such a factory with current photovoltaics or the other way around: the energy for the Tesla Giga factory could power up 2300/0.91*269= 679890 belgian families.

    Where -by looking at these numbers- I can only hope that someone looked at the Berlin/Brandenburg energy carrying capacities in conjunction with the Tesla Gigafactory protests (I was looking only at the water aspect). It was just yesterday, that there was a power outage in Berlin which left 90000 Berliner households (i.e. roughly 180 000 Berliners) without heating and so they were left freezing at minus temperatures in their homes.

  5. Gertruda Hinteregger Says:

    Thank you very much for your comment. It is quite interesting.

    Please let me just ask some final questions. Isn’t it that a lot of gas discharges are human made – the Darvaza gas crater is such an example.

    So I would like to ask you with the words of Sophia Smith Galer:

    Maybe they shouldn’t have been opened in the first place?

    And – how on earth would you deal with this crater and extract gas from such an abyss?

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