In my opinion, these studies should look at the total gamut of ICE emissions and their net effect on health, not only to a specific component like this one on PM. I don’t pretend to diminish the work behind this study, but as many other things we read or ear on media, it could be interpreted as scare tactics. “Oh my God, the diesels are coming it will be soot doom”, no word about gasoline evaporative emissions or benzene. We need the total picture not only cherry picked studies.

MH, there are plenty of studies on benzene already.

Go to pubmed and look them up...they are not new and thus, not currently in the news.

Fred: ROFLMAO, sorry I got off topic. WRT saving money ... you'll have to swear of women ... can't seem to myself ... now I'm shelling out for kids. Bring on the EV delivery trucks!

EVs don't have to pollute.

And diesels can use biodiesel and flexfuel vehicles can use E85.

Whether they actually WILL is a crucial question that needs an answer. People who push for widespread BEV and PHEV adoption, yet don't simultaneously enable major transformations in the fuel mix of the power grid towards clean renewables (among many other things), are just swapping one set of problems for another.

"just swapping one set of problems for another" ... true enough Jack. But some problems are easier to solve than others and some problems are bigger than others.

BEVs solve the car pollution end of things. That moves to onus to cleanup to the grid (not an issue where I live) which, at a limited number of fixed installations, is much easier to do than dealing will millions of moving vehicles.

While Biodiesel may be carbon neutral I'm not sure it entirely solves the pollution problem (I understand that it will greatly reduce the number of aromatics). Someone else with more knowledge of vehicle emissions will have to fill in the blanks for me on how much biodiesel is an improvement over fossil diesel.

I think what Neil is saying is that even if we burn ethanol and biodiesel we are still going to be pumping NOx and particulates into the air (even if CO2 emission are neutral), and that EV are technically more energy efficent from well-to-wheel then even hybrids.

"just swapping one set of problems for another" ... true enough Jack. But some problems are easier to solve than others and some problems are bigger than others.

Solving one problem only to create one or many more isn't actually solving a problem.

BEVs solve the car pollution end of things. That moves to onus to cleanup to the grid (not an issue where I live) which, at a limited number of fixed installations, is much easier to do than dealing will millions of moving vehicles.

That's the boilerplate response, but it still doesn't have anything to do with whether that WILL happen.

I think what Neil is saying is that even if we burn ethanol and biodiesel we are still going to be pumping NOx and particulates into the air (even if CO2 emission are neutral), and that EV are technically more energy efficent from well-to-wheel then even hybrids.

And you'll be putting more NOx into the air with a BEV than with an ultra-low emission ICE or HEV using US grid average emissions. It's swapping less CO2 for more NOx.

As for well-to-wheel, there's still a lot of dispute as to what is better than what. There's a lot of ambiguity in ascertaining what would be a complete accounting of well-to-powerplant for electricity (as well as what one assumes the fuel mix is that one is drawing from, which has massive regional and personal variations). There's an equal amount of ambiguity in the well-to-tank portion for vehicles powered by gasoline or diesel, including HEVs.

jack: You CAN sit there and do nothing. Some of us WILL and HAVE done something. I run a BEV from hydro ... no pollution. If you don't like the fact that your power comes from coal get some PV panels or pay a little extra for wind power. What's your plan?

jack: You CAN sit there and do nothing. Some of us WILL and HAVE done something. I run a BEV from hydro ... no pollution. If you don't like the fact that your power comes from coal get some PV panels or pay a little extra for wind power. What's your plan?

See - why does it always go this way? One second we're discussing the idea, the next minute someone starts getting personal. Why do you presume I'm "sitting here doing nothing"? Because I question your position with respect to some ideas? There's no logical connection that would lead to such a statement.

This isn't about what you personally are doing, or what I personally am doing, it's about the merits and drawbacks of certain technologies and how changes to one part beg consideration of how that one part is embedded in a larger system, and what and how things should change so that we're not simply rearranging deck chairs, so to speak.

And why do you presume that I get my electricity from coal? How did you come to that conclusion, too? Or how did you come to the conclusion that I'm unaware of how electricity can be produced cleanly and renewably?

Again, if we could discuss the ideas instead of getting personal, I'd appreciate it.

Neil, what would you consider comparable numbers for a Prius as a hybrid versus Prius in all-electric mode? Does 47.6 mpg and 250 Wh/mile sound right? What do you think are fair numbers?

I just want to plug in those two to compare energy efficiency, CO2, and NOx.

Nothing personal jack ... I said "you CAN" (as in generic people) rather than "YOU can" (which would be specific). I mentioned what I've been doing because I can't argue for what I think should be done unless I'm prepared to do it myself.

I don't have numbers for the Prius. From a previous article here the larger battery in the PHEV prius was 2.6kwh with a range of 13 km which would calculate out to a worst case of 200wh/km. I suggest you get more accurate numbers from CalCar. I do know that the Tesla (110 wh/km) is in the same ballpark as the EV1 (102). I don't believe that the drag coefficient of the Tesla is as good as the Prius, but it doesn't weigh as much either.

What's been getting me ticked off is that people keep comparing the very best of petro-ICE (Prius which is part EV already) with the very worst of electricity (coal). Not a very useful way of looking at the world. There may be lots of coal fired capacity in the world but there are lots of SUVs in the world too and I don't think anyone would be in doubt about how that comparison would work out. If you want to run the numbers for pollution and efficiency in a fair manner, how about comparing BEVs to petro-ICE run on CTL?

I advocate EVs as the first step on the fastest and easiest route to a clean and sustainable transportation system: EVs run on renewable electricity. The technology exists now. The infrastructure exists now. Sometimes you have to move a chair to make room for a table.

Roger can advocate H2-ICE if he wishes. I'm ok with that if it can be made to fly. It's just not the easiest route to take.

Bio-fuels are a step up from fossil, there just can't possibly be enough of it.

I suspect that NG vehicles would have some very good efficiency numbers, and their pollution numbers are an improvement over gas or diesel. Sustainability would be a problem (especially here in North America where NG production has peaked).

PetroICE is not an option. No matter how much you tinker with it, it will always create air pollution and it will never be sustainable.

This report (unless Clett is right, and I hope he is) is just one more accusatory finger pointed at problems with oil-burners as polluters.

So I repeat: Jack, have you got another alternative? Seriously I'm listening, because even the EV route is too slow for my liking.

I don't have numbers for the Prius. From a previous article here the larger battery in the PHEV prius was 2.6kwh with a range of 13 km which would calculate out to a worst case of 200wh/km. I suggest you get more accurate numbers from CalCar. I do know that the Tesla (110 wh/km) is in the same ballpark as the EV1 (102). I don't believe that the drag coefficient of the Tesla is as good as the Prius, but it doesn't weigh as much either.

Hm. For the Prius, that would come to 325 wh/mile, which seems really high. That's around what the RAV4 EV was getting 6-7 years ago. I asked because I've seen 250 wh/mile batted around as an appropriate number. I know that Tesla is claiming around 205 wh/mile at the outlet for theirs. Let's split the difference between the low Prius estimate and the Tesla and say around 225 wh/mile. Sound OK?

For the gas mileage, is 47.6 mpg OK? Those are greenhybrid-dot-com numbers.

The way I've got it, the hybrid will use 2,395 BTU per mile of gasoline and the electric-mode will consume 2,430 BTU per mile in primary energy. That accounts for overall conversion efficiency of the US grid at 31% and 114,000 BTU per gallon of gasoline. So, energy-wise, it's even.

For CO2, I'm getting 0.41 pounds per mile for gasoline, 0.31 pounds per mile for all-electric.

For NOx, the regular Prius meets Bin 2 levels of 2.0 grams per mile. The electric hits a much higher 22.0 grams per mile.

So, energy is even, CO2 is higher for the gas, NOx substantially lower for the gas. I don't really have the time to dig into all the other pollutants, and I don't even know how far I could get with it. Suffice to say, there's different chemicals coming out of a tailpipe than a smokestack and it's about which poison you want to choose - which is pretty subjective.

What's been getting me ticked off is that people keep comparing the very best of petro-ICE (Prius which is part EV already) with the very worst of electricity (coal). Not a very useful way of looking at the world. There may be lots of coal fired capacity in the world but there are lots of SUVs in the world too and I don't think anyone would be in doubt about how that comparison would work out. If you want to run the numbers for pollution and efficiency in a fair manner, how about comparing BEVs to petro-ICE run on CTL?

Yes, people do that, but I'm just trying to see what the trade-off is by keeping as much constant as possible and assuming that it's an average person who can choose between a hybrid that they can get a dealer, versus an electric the could get a dealer and just plug in. Naturally, there's individual variability, but unless one assumes changes to the electric grid (per my prior comments), then it's appropriate to assume grid averages.

I also don't think it's either/or, meaning there's room for multiple technologies, but I think it's very fair to take the edge of available technology and compare it to whatever is similar, yet with a different type of engine/motor and energy source.

This comparison with the two Prius models seems to validate what I was saying about trading one problem for another and that it's not necessarily true that a pure EV is more efficient than a hybrid. Again, this isn't full well-to-wheel, but anything past the power plant and the gas pump is speculative at best and thus open to wide ranges of values.

So I repeat: Jack, have you got another alternative? Seriously I'm listening, because even the EV route is too slow for my liking.

I'm actually happy with the progress of hybrids and EVs. It really looks like we're hitting strides with them now and it won't be too far off that they'll be far more common. It mostly hinges on storage density, economics, and recharge times, all of which are trending favorably at a good clip.

Long-term, I'm not really banking on personal road vehicles, though, so it's not the greatest concern to me. It seems to have run its course as a technology, relative to other things we're capable of deploying in the near future.

Hi Neil,
Your (and mine) passion in advocating Green Automotive is what society needs now more than anything. Your partiality toward BEV is understandable since you're receiving electricity from hydro source. But, keep in mind that Hydro-electricity has little room for future expansion beyond what it is now.
I'm getting my electricity from mostly coal-burning plants at a ripoff price of 15 cents/kwh, and there are local outcries where I live regarding air pollution from these local coal-burning power plants.

I'd like to make a motion that we (the world) should make a transition away from petroleum-based transportation, and toward renewable energy sources. WE now have the technology to synthesize transportation fuels efficiently from renewable energy sources, in order to back up unreliable solar and wind output AND also to power our transportation.
However, we can still continue to count on the [cleaner and leaner] ICE as our powerful ally even in this respect. The recent news about Ford and DB being close to bringing to the market HCCI-capable engines with 20-40% improvement in efficiency is even more encouraging for the continued contribution of the ICE in our future transportation.

When fuel cell technology will make FCV-HEV practical economically, then even more power to Green Automotive. Ditto for nanotech battery technology. But, let's not count the chicken until the egg is hatched. Peace.

We all know that AWD BEVs is by far the best solution and ICE vehicles are one of the worse. ICE will have to go the same way as tobacco smoking went. The argument of diesel versus gas/ethanol ICE is irrelevant, much the same as 'filter' cigarettes versus 'non-filter' was. They both have to go.

The logical transition, for personnal transportation, may very well be via HEVs and PHEVs but sooner or latter BEVs will win. A very light weight BEV covered with 50% efficient solar cells could cruise around at an acceptable speed (on sunny days) without using much of the on-board battery energy.

Electric passenger trains have proven the most efficient and often the best way to move people around quickly, safely and cleanly. European countries have adopted that solution while North America has not. We will wake up sooner or latter.

Electric (daytime) flights are also coming and will be common place 15 or 20 years from now. Battery or Fuel Cell range extenders or both could be used for night time (and cloudy days) flights.

Electric flights??

Jack:

Primitive (early days) limited range and payload electric flights are a reality. Check with Boing R & D.