Wednesday, July 4, 2012

Diesel Fumes and Cancer. Buy EV instead!

The World Health Organisation has concluded in a recent panel ruling, as reported by the Guardian that fumes from diesel engines cause cancer, at about the same rate as standing in a cigarette smoke-filled room, or copping too much sunburn.

This is interesting to me, because diesel cars are something I hear put forward as environmentally sound motoring choices.  [edit] In 2009 according to Wired's Autopia car site, Green Car Journal named a diesel as its Green Car of the Year.  I say interesting because that was 2009, now we have electric vehicles (EV's) and I struggle to see how those diesels are green by comparison.  Another article says forget about "black plumes of smoke, noisy engines" because diesels are clean and green now.  Maybe when they are brand new - but I see plenty of 5-10 year old "modern diesels" on the road producing black smoke.  It doesn't matter how old an EV is it is never going to produce smoky fumes.

Also, when I talk to people about Electric Vehicles I still get this recycled FUD about the long tailpipe, which is basically this idea that EV's "emit pollution" from the power stations that they draw electricity from.

The WHO panel ruling shows how bogus this is - what the actual vehicle itself is emitting is important. If you are on the footpath going for a cappuccino, and you find yourself next to several lanes of traffic in the city then each vehicle that is emitting pollution from its tailpipe is damaging you.  For children playing in the schoolyard next to a busy major road then they are being exposed to carcinogens from diesel exhausts of vehicles on that road.

EV's have no tailpipe, and no exhaust fumes.  Even if they were charged the previous evening from the most fiendishly polluting power source, when they drive on the road no pollution is being emitted from those EV's into the busy urban and suburban environments that we live in, work in, and send our kids to school in.

Getting back to the diesel thing, when I drove a Prius, before getting the Nissan Leaf, I would also hear quite often an argument that diesel cars were a good environmental alternative because they did a better mileage than the Prius in some cases.

If you look at popular diesel hatchbacks like the Ford Focus, or Peugot 308 they are in the same league as the Prius for consumption figures:

CarEmissions gm/kmConsumption ltrs/100km
Prius 1.8 Hybrid T3 2009923.3
Peugot 3081194.0
Ford Focus TDci diesel1574.8

Now the first thing to notice is that emissions is not consumption.  The Peugot for example does pretty well on consumption, using 1.2 times as much fuel per distance as the Prius.  However its emissions are 1.3 times that of the Prius.  For the Ford Focus the fuel usage is 1.45 times that of the Prius, but its emissions are 1.7 times worse!

How can this be?  Isn't the petrol here the source of the emissions?  Surely if you burn 1 litre of fuel, you create some fixed amount of pollution?  A moments thought shows that this is wrong, because engines ain't engines: some are more emissions efficient, not just mileage efficient.  The Prius has an Atkinson cycle engine, which can take advantage of its electric hybrid transmission to operate in an optimum range, meaning that it produces less emissions for a given amount of fuel burnt.  The Prius engine is very mileage efficient, but that is almost just a side effect of the engineering put into making it very very emissions efficient.

So, getting back to the argument above - diesels are good environmentally because they do better mileage - you can see that this is just plain wrong.  Better mileage does not equal better emissions.

And now we know from the WHO study that those diesel emissions are carcinogenic, as well as being a greenhouse gas pollutant.

The thing with electric vehicles, is that not only do they produce no tailpipe pollution emissions at all - they can also use clean, greenhouse-gas free electricity from sources like solar and wind.  You could cover Australia in solar panels and the diesel and petrol cars on the road are still going to be producing just as much pollution as they always did.  In fact it doesn't matter how far science advances, in cleaning up our local Australian-grown energy production, if you stick to fossil-fuel powered cars none of those advances can help our pollution problems at all.

Electric Vehicles can take advantage of home-grown energy solutions, instead of costing us in expensive oil imports in many cases from countries that none of us want to be beholden to.  Diesel cars, no matter how mileage efficient still get their fuel from foreign oil.  Think about it: where do you want your motoring dollar going to; the Middle East or to buying Australian?

Now I hear some people say that they have to drive to Sydney or, as we say in Australia when talking about long distances "to the back of Bourke".  Because of these long trip requirements they just can't buy an Electric Vehicle.  Really?

There's lots of things that people expect of their vehicles - it must be able to take me fishing on the beach at Stradbroke Island, or I must be able to load the surfboards, wetsuits and a Esky full of beer into the back.  Or it has to be able to do zero-to-sixty in 4.2 seconds.  Now add to that list of expectations this idea that a car has to be able to drive interstate on a tank of gas.

Realistically I think for 95% of us, those requirements are just not logical criteria to use for choosing the car you drive every day.  For many cars are an emotional thing.  We want a ute or pickup; or we want an SUV or 4WD, or a sports car.  A big full tank of gas equals freedom and self-determination.  But think about it, the 100th time you're trying to back that thing into a parking spot in the supermarket, or navigate city traffic, or stretching to afford the best part of $100 to fill the tank up to full.  Was that really the best decision you made on a vehicle?

For some of us, those emotional things; they're deal-breakers - OK.  If for some reason you have to drive to Sydney, or your commute is hundreds of miles then go and buy a Prius.  The Prius is a great car, with loads of room in the back, and it goes places that any other road car can, and further besides.

But if, like me you can take advantage of an Electric Vehicle for emissions free motoring, never ever having to buy gas, just go ahead and do it.

Your lungs will thank you.


  1. By the way, I got a comment from my fellow Australian readers that I was getting far to USA - centric in my posts, and when I scanned back they were right.

    After living and working in California for a while, and having to remember that unless you said "gas station" or "miles" no-one would know what you were talking about, my writing has permanently got stuck in the USA frame of reference.

    I've tried to correct that a bit in this post. Hope y'all approve!

  2. Hey Sarah,

    I'm currently able to use my mother-in-law's Prius. After 6 weeks I've found new (to me) pros and cons to it in terms of driving characteristics.

    The twos biggest reasons we didn't get one when we last bought a car (Corolla, station wagon 2004 model; bought 2nd-hand end 2006) was we were looking for something with good cabin space and the stupid, stupid, stupid "space-saver" spare. There's nothing "space-saving" about a tyre that only allows you to travel 40-60km (when you're 100km from any tyre repair facility - we were moving to Mackay) while having to find room for the full-sized regular wheel in your already full cabin compartment because it won't fit in the "space-saver's" housing.

    I do like the fact it gives you the option of EV only so if you're in an enclosed carpark (where emissions are an issue) or you're leaving the house at some horrible time in the early AM (when noise is an issue) you can switch to that.

  3. Hi Laetitia, thanks for the great comment. It's interesting to hear your views and experiences with the Prius. Did you actually get a flat tyre and need to use it? I'd be interested to hear how you went with that. A lot of people just ring up RACQ I think.

    When we were in the 'states we got two punctures resulting in flat tyres. One time it was a large nail, the other it was a bolt. Both times we were able to inflate the tyre enough with a foot pump that we carried in the tool-well to drive the car to get it repaired, so we never actually had to deploy the spare.

    My understanding is that the space saver is there to allow you to reach a repair place and get the flat fixed. Part of the problem is that people run around for weeks with the space saver on at highway speeds and they are just not designed for that. Just doing some googling it seems that people have driven more than 60km without incident. I think what Toyota are doing is saying that they don't support that. I would be interested to hear any stories of space saver spare tyres failing when driven for a few hundred kilometers - with all the anti-Prius FUD out there if that happened I am sure it would have showed up on Google, but I couldn't find anything.

    Apart from the "space saver spare" issue, how have you found it to drive and use? One of my colleagues [at my old job at Nokia] has two children and says he finds his Prius really good. But I'd be interested in hearing other experiences. My view is that many people buy enormous 4WD's for "space reasons" and yet I'm not convinced - I think its this feeling that the ride height in a 4WD gives - see the "Canyonero" episode of "The Simpsons". :-) I guess it has the advantage of fixing baby seats in the rear when those are at standing height. Obviously in a hatch or sedan you have to bend in to operate a child seat. As I say my colleague says he has no problem with this.

    Ray and I found the Prius to be a big car, and very roomy - certainly we would not have had room to fit anything bigger in our garage. It's strange but a lot of people seem to think the Prius is this small runabout - for example Rays' Dad was saying "you should get a bigger car like a VW Golf" - the Prius is a few 100mm bigger in all dimensions than the VW Golf.

    According to the overall length of the Prius is 4445L x 1725W x 1490W and the Toyota Conquest Station Wagon is 4385L x 1695W x 1475H, both for 2004 models.

    Ray's Dad also does not like the space saver spare. I guess its better than some cars which only offer a pressurised can.


Hi, thanks for leaving your thoughtful on-topic comment!