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Mazda Says Its Upcoming Gas-Powered Cars Will Emit Less CO2 Than Electric Cars
cartechboy writes: "One of the arguments for electric cars is that we are reducing greenhouse gases and emitting less CO2 than vehicles with an internal combustion engine. But Mazda says its next-generation SkyActiv engines will be so efficient, they'll emit less CO2 than an electric car. In fact, the automaker goes so far as to say these new engines will be cleaner to run than electric cars. Is it possible? Yes, but it's all about the details. It'll depend on the test cycles for each region. Vehicles are tested differently in Europe than in the U.S., and that variation could make all the difference when it comes to these types of claims. At the end of the day whether future Mazdas with gasoline-powered engines are cleaner than electric cars or not, every little bit in the effort to reduce our carbon emissions per mile is a step in the right direction, right?"
Interesting notion, but the devil is in the details. In the NE United States most of the electricity is from coal or gas fired plants, but in the NW United States most of the electricity is hydropower. You can argue that the carbon footprint of the NW electricity is very low, but if you consider the carbon cost of building the dams, the carbon goes up. You have to make assumptions about the expected life of a dam so you can pro-rate the carbon cost. The same issues surround calculating the carbon cost of nuclear generated electricity, but you also have to include carbon coats for transporting, storing, and guarding the nuclear waste for a long time, which involves another assumption. There are also a host of carbon issues relating to power transmission infrastructure. There is a lot of steel in those towers, but some of it is a century old. Do you count it in current carbon calculations?
The bottom line is, the assertion that the Mazda has a lower carbon footprint is more of a marketing claim than an engineering calculation. I suspect the assumptions involved have been made with the primary purpose of supporting the claim rather than meeting some test of reasonableness.
If you ask a question from a marketing context, you get a marketing answer.
And those levels would likely be better than the wells-to-wheels carbon profile of an electric car running in a coal-heavy country--Poland, for example.
Not only that, but the engines themselves are not yet designed. They are "projected" be available by 2020.
I realize the air is a bit dirty, but still -- That is a long time to hold your breath.
Great civilizations have lived and died on false theories. Don't mess up mine with a few facts.
Mazda abuses copyright to stop 3rd parties from publishing manuals. Can't get a Haynes or Chilton manual for any Mazda newer than about 1995.
http://www.haynes.com/products... 2 seconds on Google.. come on, man.
So the only real way to reduce CO2 emissions per mile is get more miles per gallon of fuel.
No. My ~40mpg motorcycle pollutes far more than my ~27mpg car. It's all about how well the engine burns the fuel and handles the emissions before they leave the pipe, not necessarily just the volume of it.
This MYTH has been debunked:
"A study by M.A. Weiss et al., published in a 2000 report from the MIT Energy Laboratory, On the Road in 2020: A Lifecycle Analysis of New Automotive Technologies, calculated that fully 75 percent of a vehicle’s lifetime carbon emissions come from the fuel it burns, and another 19 percent was due to the extraction and refining of that fuel. The raw materials making up the vehicle added another 4 percent, and just 2 percent of lifetime carbon was due to manufacturing and assembly. In other words, you'll save a lot more energy if you junk your old car and buy a much more efficient new one."
And as everyone in this thread knows, energy == emissions for all practical purposes...
Breeding means generating more nuclear fuel from stuff that is not fissile material in the first place. For example, in a classic nuclear fuel rod only a few percents of the uranium is of the 235 isotope variety, which is fissile (= radioactive, potentially dangerous and useable as nuclear fuel), the rest is the 238 isotope and is not fissile... but is intead "fertile", because once it gobbles up a passing neutron (= beta radiation), it quickly transmutes into the 239 isotope of plutonium - and this kind of plutonium, in turn, is fissile.
And, fortunately, you can have it so that while the 235 uranium "burns" it produces the right neutrons for the 238 to turn into 239, or "breed" into plutonium. Or breed the fertile 232 thorium into fissile 233 uranium, too. That's the principle of a breeder reactor. And you may use your fresh new fuel to breed yet some more fuel, too, so that potentially, all the uranium and all the thorium in the world may be converted into nuclear fuel - that's called "supergeneration", because then you are not even limited by the tiny amount of starting fissile material anymore.
For every amount of starting fuel you can have various ratios of breeding happening. In fast breeder reactors you can have three or four times more breeding than consuming, so that every unit of fuel spent generates, on the side, three or four units of additional fuel from fertile material. In molten salt thorium reactors this ratio is projected to be 1-on-1 to limit the risks of nuclear proliferation (= using the breeding process to make a lot more fissile material, in order to make weapons).
Maybe we deserve this world ?