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?"

Comments

Do electric cars actually produce CO2?

[kruach aum]

Or do they mean in the "yeah but guess where that electricity comes from, a coal-burning plant" sense?

Re:Do electric cars actually produce CO2?

[Moheeheeko]

If that were the case I would point them to the refining process for gasoline.

Re:Do electric cars actually produce CO2?

[Todd Palin]

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.

Re:Do electric cars actually produce CO2?

[K. S. Kyosuke]

I don't think it's just refining, mere drilling and pumping requires progressively more energy as we've already consumed all the low-hanging fruit.

Re:Do electric cars actually produce CO2?

[knarfling]

Exactly!! The TFA (I know, I know. Why read the TFA.) calls it the wells-to-wheels carbon profile. And Mazda is comparing only to the "dirtiest" areas.

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.

Re:Do electric cars actually produce CO2?

[DittoBox]

Also consider how the materials for the batteries are sourced (emissions/energy cost to mine), where they're sourced (emissions/energy cost to ship), how they're put together (emissions from factory, energy cost), and where the entire vehicle is put together (emissions/energy cost to ship batteries to car factory). Is continuing to use older vehicles less and more impactful to the environment?

People who are totally against innovation in this sector tend to think all of these are worse than continuing to rely on dead dinosaur-based fuels. I think we need to push forward and research all options, including reducing individual demand for vehicular use through public transit, better civic planning, automated vehicles (which increase efficiency in the system greatly) among other options.

I'm a car guy and I desperately do not want to see organic fuels disappear because of over use or damage to the environment. I think converting to more efficient travel methods and shrinking work-to-home distances are ultimately the way to go. Having access to fossil fuels in the future will then be reserved mostly for folks who just want to have fun, like owning horses is today. I don't want to see track days go away, or being able to take apart and put back together an almost entirely mechanical engine. There's a certain mechanical hackery to it.

Cars as appliances need to move on from fossil fuels, cars as projects/things to hack shouldn't. If we continue to treat fossil-fuels as infinite and undamaging we're going to lose cars as toys and projects and things to hack. That's sad.

Re:Do electric cars actually produce CO2?

[Lumpy]

Not for me, I get my power from Nuke plants. it's the most environmentally friendly power source out there. IF the government was not filled with retards and allowed the spent fuel to be used in breeder reactors.

Nuke is better than anything else, it's the morons in DC that make it less than perfect.

Re:Do electric cars actually produce CO2?

[Solandri]

Yes, I've heard the 6 kWh figure too. Assuming it's true, I suspect it's the cost to refine a volume of crude oil which yields a gallon of gasoline. So the 6 kWh would actually need to be amortized over the other petroleum products too, not just the gasoline. The EIA says a barrel (42 gallons) of crude oil yields about 19 gallons of gasoline. So if I'm right, only 2.7 kWh is attributable to the gasoline. (This isn't strictly correct because I believe 42 gallons of crude oil yields more than 42 gallons of product - such are the pitfalls of working in volume instead of mass.)

The 300 Wh is also the electrical energy stored in the battery (the Tesla S has an 85 kWh battery rated at 300 miles, so that works out to 283 Wh/mile). If you're going to factor in production costs of gasoline, you also need to factor in production costs of electricity. Charging the battery is about 75% efficient. Transmission to the home is about 98% efficient. And coal plants are about 45% efficient. So to produce the 300 Wh/mile the EV uses, the power company actually has to burn 300/(.75*.98*.45) = 907 Wh/mile. Factor in coal mining and transport costs and you're probably up around 1 kW/mile.

So the energy cost to refine gasoline is probably more likely enough to drive the EV only 2-3 miles.

Re:Do electric cars actually produce CO2?

[Jesrad]

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).

Re:Mazda is not open

[twotacocombo]

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.

Re:Ummm....

[twotacocombo]

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.

Re:Ummm....

[robot256]

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...

Re:Ummm....

[Rising Ape]

CO2 emissions are directly proportional to fuel consumption (for a particular fuel). It's the other emissions - CO, hydrocarbons, nitrogen oxides etc. that can vary dramatically.