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> I'll keep my very efficient Audi diesel car (79g/km CO2) for now thanks. I did not have a point of reference to see in what sense this is efficient or not, s

> I'll keep my very efficient Audi diesel car (79g/km CO2) for now thanks. I did not have a point of reference to see in what sense this is efficient or not, so I checked how much CO2 humans exhale. It turns out your car emits about as much as 2 humans exhale. Here's the math: - car: on average people drive about 10000 kilometers/year in the UK [1], so if you drive like an average person in the UK, your car puts out 790 kg of CO2 in a year - humans: on average people exhale about 2.3 pounds of CO2 per day [2]. That makes about 762 kg/year for 2 people [1]https://www.thecarcrashdetective.com/americans-drive-more-dying/ https://www.thecarcrashdetective.com/americans-drive-more-dy... [2] https://www.nrdc.org/onearth/waiting-exhale https://www.nrdc.org/onearth/waiting-exhale

oddeyed 5y ago
Not necessarily comparable for purposes of global heating effect (not sure if that's what you're doing or not). The CO2 that a human exhales is from the carbon in the food they consume. That carbon ultimately comes (whether indirectly via animals or not) from plants, which drew that CO2 out of the air directly, typically at most a few years prior. The net change in CO2 concentration is zero. Contrast this to burning fossil fuels which moves carbon from places where it is not enhancing the greenhouse effect (e.g. it's in coal, gas wells or crude oil) into the atmosphere where it will cause global heating - a net increase in CO2 concentration. As a side note, methane produced by livestock or food waste does still have a global heating effect as CH4 is a more "potent" greenhouse gas than CO2, so there is a net increase in heating potential due to this conversion.
hutzlibu 5y ago
What you should not forget is, that CO2 isn't the only gas emitted by diesel cars. Gases and dust, that are a serious health hazard en masse in cities. Also I doubt that the 79g/100km is the full number, that includes drilling for, refining and transporting that diesel to your car, before you can burn it there. And btw., those kids in africa are poisening themself with ICE car parts too. So I don't think anyone said, we should all wreck our ice cars today and go all electric immediately. That clearly makes no sense ressource wise. But in the long run, yes. I want noise, smoke, fumes and dust free cities as soon as possible, along with a somewhat stable and intact environment. You have to start somewhere.
- zip1234 5y ago
  In cities we should be encouraging e-bikes more in my opinion. They take up much less space than cars, are quieter, cheaper, and healthier. Even electric cars make almost the same amount of noise at speed as ICE cars and still emit dust from breaking down tires.
imtringued 5y ago
For humans to breathe out CO2, they must eat animals or plants. Animals also eat plants. Plants obtain carbon from the atmosphere by capturing CO2. Of course I am ignoring CO2 emissions caused by industrial agriculture and those should not be understated but breathing alone doesn't contribute any net CO2, it's the industrial process that does it.
Workaccount2 5y ago
Humans emit recycled CO2 Cars emit new CO2

oddeyed 5y ago

Not necessarily comparable for purposes of global heating effect (not sure if that's what you're doing or not). The CO2 that a human exhales is from the carbon in the food they consume. That carbon ultimately comes (whether indirectly via animals or not) from plants, which drew that CO2 out of the air directly, typically at most a few years prior. The net change in CO2 concentration is zero. Contrast this to burning fossil fuels which moves carbon from places where it is not enhancing the greenhouse effect (e.g. it's in coal, gas wells or crude oil) into the atmosphere where it will cause global heating - a net increase in CO2 concentration. As a side note, methane produced by livestock or food waste does still have a global heating effect as CH4 is a more "potent" greenhouse gas than CO2, so there is a net increase in heating potential due to this conversion.

hutzlibu 5y ago

What you should not forget is, that CO2 isn't the only gas emitted by diesel cars. Gases and dust, that are a serious health hazard en masse in cities. Also I doubt that the 79g/100km is the full number, that includes drilling for, refining and transporting that diesel to your car, before you can burn it there. And btw., those kids in africa are poisening themself with ICE car parts too. So I don't think anyone said, we should all wreck our ice cars today and go all electric immediately. That clearly makes no sense ressource wise. But in the long run, yes. I want noise, smoke, fumes and dust free cities as soon as possible, along with a somewhat stable and intact environment. You have to start somewhere.

zip1234 5y ago
In cities we should be encouraging e-bikes more in my opinion. They take up much less space than cars, are quieter, cheaper, and healthier. Even electric cars make almost the same amount of noise at speed as ICE cars and still emit dust from breaking down tires.

imtringued 5y ago

For humans to breathe out CO2, they must eat animals or plants. Animals also eat plants. Plants obtain carbon from the atmosphere by capturing CO2. Of course I am ignoring CO2 emissions caused by industrial agriculture and those should not be understated but breathing alone doesn't contribute any net CO2, it's the industrial process that does it.

Workaccount2 5y ago

Humans emit recycled CO2 Cars emit new CO2