Saving the environment without looking stupid: A primer

The other day, I got in an argument with an eminent and highly respected man - and, just to make me feel even more of a jerk, his lovely wife - about cars.

Unfortunately, cars were not his strong suit.

I didn't ask, but I'm perfectly certain that he has never watched Top Gear.

But, like most people who've been driving for a lot longer than I've been alive, he's pretty sure that he knows more about cars than me.

He and his wife own, and adore, a Toyota Prius.

The Prius is very good at exactly one thing. That thing is consuming small amounts of fuel in city traffic.

Hybrid cars are made for city traffic, because they stop their engines when they're sitting still. Every other car keeps its engine running when it's stationary, sucking down fuel at a magnificent zero miles per gallon. Hybrids don't. So, in city traffic, they get something pretty close to their highway fuel economy.

("Litres per 100km", by the way, is the standard Australian measure of fuel economy. It is stupid. It turns people's brains backwards when they try to figure out how far they can go on X litres of fuel, and it's also an inverted metric compared with miles per gallon - more mpg is good, but more l/100km is bad. If we used kilometres per litre, one of which equals 2.35 miles per gallon, I wouldn't have a problem. But we don't, so I'm sticking with the lesser of two evils and using miles per gallon.)

This excellent fuel economy in stop-start traffic, plus the lower pollution contribution of a car that doesn't run its engine when it doesn't need to, makes a hybrid an excellent vehicle for people who do a lot of city driving.

Out on the highway, hybrids still get decent mileage, but not because they're hybrids. They do OK on the highway because they're light (which means aluminium, which contributes to the cars' price), and have excellent aerodynamics, and have low rolling resistance tyres - like when you pump normal tyres up to 60psi, but, you know, safe.

Some hybrids, like Honda's Civic version, even use special low viscosity oil. The Prius doesn't, though.

Hybrids get some assistance from their electric motors on the highway, when overtaking or trying to maintain speed up hills. But that's because they've got weedy little engines (76 whole horsepower at 5000RPM, for the current Prius - I think that's actually beyond the engine's redline) that need that assistance. You can save a lot of fuel if you manage to avoid accelerating up hills, but hybrids can't entirely avoid that unless you let significant speed wash off when travelling uphill.

Unfortunately, my statement of this fact, and my further observation that the choice of informed fuel misers for all-around driving is actually something like a Volkswagen Golf TDI, went down like a lead balloon. My conversational companions were firmly convinced that the only things that sipped fuel slower than their Prius, in any situation, were glorified lawnmowers incapable of comfortable highway driving.

They'd seen it for themselves! They'd driven from Sydney to Melbourne - about 900 kilometres - on eighty Australian dollars worth of petrol!

My observation that I could do that in my dented 1995 Nissan Pulsar - if you can manage 35 miles per gallon on the highway, you're there with a hundred kilometres to spare - was received with disbelief.

(Actually, I think they might have said they went there and back on $80 worth. That'd require a minimum of about 62 miles per gallon, which I don't think any human has every managed to wring out of a Prius on public roads. About 55mpg is the best I've ever seen reported.)

Things really went downhill when I foolishly mentioned that the Prius does not handle well.

Which it doesn't, because it's physically impossible for it to do so. Priuses have a comfortable ride and low rolling resistance tyres, and therefore cannot possibly grip the road very strongly.

Handling is, of course, absolutely one hundred per cent irrelevant to most drivers most of the time, especially if they're driving a car with stability control (which the Prius has). Stability control lets an ordinary driver in a low-grip car successfully cope with unexpected situations which would probably defeat an excellent driver in a high-grip car. It's amazing, it's almost magical, and it's a crime that it's still practically impossible to find in cheap cars.

When push comes to shove, though, a Prius does not have a very large performance envelope, and traction control cannae break the laws o' physics. It is easy for a Prius to run out of traction, and when it does... understeers directly to the scene of the accident.

I did not succeed in explaining this to my conversational partners, who firmly insisted that their Prius had excellent handling.

My working hypothesis is that this is because they do not actually know what handling is, and have confused it with ride comfort.

I freely admit to making a further blunder when they pointed out that their other car also has excellent handling, and volunteered the information that it's another Toyota.


I couldn't help, at this point, blurting out that this proved that they knew nothing about cars at all.

Which I should not have done.

I shall draw a discreet veil over the rest of the conversation, except to mention that the phrase "we'll agree to disagree" was directed at me.

I have used that phrase myself. When I use it, it means "You're wrong, and stupid, and I would like you to be quiet now". I suspect it might have meant that in this case, too, since when I offered to e-mail the gentleman the evidence, he said he'd rather I didn't.

Anyway. To finish off, here are the three basic classes of very economical car that normal human beings might want to own, while we're waiting for that groovy modular automobile to come along.

1: A Prius.

Great in town. Tolerable on the highway. Bad if you have to steer suddenly to avoid hitting something. New and shiny and nice.

Insofar as there exists such a thing as "an average driver", a Prius is realistically good for a quite remarkable 50-plus miles per gallon overall if you're careful, and 45mpg even if you're not.

You could probably abuse a Prius into delivering only 40mpg if you really tried. Lots of very short trips would do it, if you don't make judicious use of the EV button. But you wouldn't have a lot of fun doing that, which rather defeats the purpose of wasting fuel.

2: A Volkswagen Something-Or-Other TDI.

The 1.9 litre Volkswagen turbo diesel, when mounted in its natural habitat (a Golf), is good for a perfectly realistic 55 miles per gallon. Maybe only 45, if you're a more excitable driver and/or have an older Golf.

You can get at least one and a quarter new diesel Golfs for the price of a new Prius, at least here in Australia.

Like all other diesels, the TDI can run on biodiesel, which gives it more environmentalist bragging points than any petrol Prius will ever have.

3: An old-ish diesel, canonically a Mercedes-Benz 300D in an unattractive colour.

A decent 300D will cost you a tenth as much as a Prius. Its fuel economy and general performance are both quite unexciting - though it wouldn't surprise me if an orange 300D wagon could beat a Prius around a track - and it very conclusively lacks stability control, though you don't have to pay much to get one new enough that it at least has anti-lock brakes.

The Unique Selling Point of cars like the 300D is that you can run them on waste, or even fresh, vegetable oil.

In theory, you can do this with no conversion equipment at all, if you live in a nice warm place like Australia (the oil thickens in cold climates, requiring tank heaters and/or a dual fuel system). In practice, you'll need a new fuel filter and maybe a new hose or three.

But that's all, for a $3000 car (donate the money saved to the dolphin-hugging organisation of your choice), with most modern conveniences, that runs on filtered fry grease.

Thereby putting to shame even the biodiesel crowd, let alone those dinosaur-burning Prius drivers.

Here in Australia, big cans of brand new vegetable oil currently cost, at retail, only about 1.5 times as much per litre as mineral diesel.

A huge plastic tank of filtered waste oil meant for animal feed will probably cost you quite a lot less than mineral diesel, even including delivery by a confused fellow in overalls who can't figure out where you're hiding your cows.

28 Responses to “Saving the environment without looking stupid: A primer”

  1. nmr8 Says:

    well, better to be an ass beholden to truth than an ass beholden to power eh

  2. Nogami Says:

    I didn't actually find the stock OEM tires on my Prius ('04 model) to be that bad - Goodyear Integrity as I recall. I took it through a number of supervised emergency driving exercises in both dry and wet-weather conditions and it handled all of them without issue.

    That said, when it came time to replace the tires, I went with some Goodyear TripleTreds that don't have the LRR rating, and will likely cut a couple of l/100km off of my savings, but the sidewalls are less flexible (better cornering), and I upsized from 185s to 195s for a slightly wider footprint. I also run my tires at 40/38 psi, rather than the 34 that the dealership usually inflates to (providing a smoother ride I suppose). As the tires are rated up to 44, it should be fine.

    I'm not a big diesel fan because of the particulate emissions (and with the possible exception of biodiesel (which I've never smelled), regular diesel burns with an odour that irritates my nose/lungs).

    Top Gear is a fun show to watch, but I don't think they really go out of their way to provide scientific testing - they have a definite preference for European luxury (read: costs more than my house) cars, which is evident in their reviews.

  3. Daniel Rutter Says:

    Of course they do, as they frequently and shamelessly admit :-). They're three blokes given the choice of driving Bugattis, or driving Hyundais. Hmm. Tough.

    Top Gear is an entertainment show, with a modicum of actual information. That's right there on the label, and I can understand why people can't bear the whole show just because of Jeremy "Global warming? What global warming?" Clarkson. Top Gear won't even give a Prius a proper review; Clarkson did a pseudo-review of one, but it was essentially just him saying how much he hated it over and over. And then he went off and spent a medium-sized fortune on a huge sexy Ford that didn't bloody work :-).

    It is not, however, controversial to observe that Priuses (with, as you say, their standard super-economy tyres), and RAV4s for that matter, have positively comically bad handling by modern standards. Which is fine, really; handling is not what they're for, the Prius is an excellent city car, and Americans will buy anything anyway.

    If you've got the option, though, you can buy better.

    (Biodiesel burns sweet and clean, by the way. But if your own car's exhaust manages to irritate your lungs, that suggests to me that your car has a leaky exhaust system and a rusty floorpan. :-)

  4. tr Says:

    Go on then Dan, enlighten us!

    What car do you drive? And given unlimited budget, what car(s) would you park in your garage?

  5. David Says:

    He would drive a McLaren F1, of course. If that isn't the paradigm of engineering, surely nothing else would qualify.

    One would hope it comes with a theft-deterrents. Flashing lights, loud noises, Robocop electrocution system.. there's something to be said for the trifecta.


  6. mookers Says:

    I would love to know what Dan suggests for the petrolhead who wants to be (at least somewhat) environmentally conscious.

  7. Oosh Says:

    Most anything 2L and turbo'd will achieve reasonable, if not miserly, fuel efficiency when you're driving Miss Daisy and come alive when you jump on the loud peddle.

    While singing the virtues of VW Golfs the GT with its 1.6L Twin-charged (Super and Turbo) engine looks to fit the bill.

    It's just a shame cars are so porky these days, the manufactures need to step up their use of Al and composites in the everyday line-up, rather than just the exotics.

  8. Rob L Says:

    I was waiting for a link to Fifth gear's (the poor man's Topgear) vegetable oil diesel challenge, where the've driven an Old diseasel Merc across merry olde' running on chip fat and have now attempted a speed (run for the hills) record.

    Naturally the truly green hoon (groon?) would one of these.

    And if your budget does stretch to a Lotus, look at any lightweight sportscar MX5, MR2, Smart Roadster, Clio Sport or a Clubman.

    It IS a shame cars are so heavy, but really manufacturers are just giving punters (and legislators) what they want, CHEAP, safe, reliable, lots of gizmos and with all the requisite anti pollution gear.

  9. reverb Says:

    Have a Polo (little Golf) TDi and consider myself a dieselhead. Feel free to get them chipped up to 100kw/320Nm and still run them on biodiesel. Mine's standard and goes plenty hard enough to surprise the local Falcodore drivers, especially in mid-range. Weighs less than the Golf so goes harder as they use the same engine (1.9L). Cheaper too.

    Just learn to short-shift and any revhead will be happy with any current diesel, while feeling green-ish by running on bio, processed waste oil or even pump diesel (still using significantly less refining and raw material than petrol).

  10. reyalp Says:

    As long as you are going to rant about units... MPG sucks as a measure of efficiency too. From an emissions perspective, you care about mass (or perhaps just what fraction of the mass isn't hydrogen.) So you really want to find the lowest Brake specific fuel consumption, in the smallest, most aerodynamic shape that meets your performance needs. Replacing miles/gallon with miles/pound would be a good start. This lessens diesels apparent advantage slightly (since it is denser than petrol), but it still wins. Other less dense fuels such as LPG, alcohols, CNG and hydrogen suffer in MPG comparisons for the same reason. Of course, in the cases of CNG and especially hydrogen, the volume is big enough to become a problem in it's own right.

    Note that you really don't want to just dump straight veg in the tank of your diesel like they do in that 5th gear clip. You'll save yourself a lot of trouble if you filter it beforehand and install a heated tank and cleanable filter just for the veg. This doesn't take much more than basic plumbing skills, and there are plenty of sites on the internet that will tell you how to do it.

  11. reyalp Says:

    oops strike alcohols from that last comment.

  12. dave Says:

    Well, if you want to rant about units, at least do it properly. Don't talk about mass of fuel burned per mile, Talk about automotive fuel like they do wholesale natural gas - in energy: Joules (or megajoules or petajoules, depending on the scale, obviously).

    That would solve any problems people have about ethanol or LPG getting less MPG (or the erroneous comment that putting ethanol in petrol is like putting water in your tank...ahem!), as the MPJ reading would be wholly dependant on the efficiency of the engine and the losses inherent in the car, not the fuel.

    (At least not directly - the engine efficiency will most likely change as the combustion of different fuels in the same engine will be different - especially as the spark timing and compression ratio, etc are likely to be tuned to a particular fuel spec.)

  13. Itsacon Says:

    Big problem with using store-bought or used vegetable oil as fuel is that it's, well, illegal.
    Unless of course you keep all the supermarket receipts and make frequent drives to the tax offices to pay some additional taxes.
    Legislation for this may vary between countries, but I know that it applies to most countries in Europe, at least.
    This site does go over that part pretty well, including the numbers of the forms needed if you live in the UK.

    Oh, and it DOES make you exhaust fumes smell like you have a fish 'n chips store in the boot...

  14. Daniel Rutter Says:

    The tax laws are (a) so completely stupid that I don't see much point in even paying them the compliment of mentioning them and (b) not applicable to Australia. Here, biodiesel is an excisable fuel (I'm sure every greenie busy cooking up his own in the garage for personal use is very careful to keep track of how much he's made...), but vegetable oil is not.

  15. Itsacon Says:

    Sorry, being a Dutchman, I'm obviously not very familiar with Australian tax procedures... :-)

    Interesting to see these things vary so much. Over here, people have gotten into serious trouble over this.

  16. Andy Says:

    Don't get me started! The whole "Ride and Handling" thing really annoys me. Even some [so called] respected reviewers lump the two together. Totally meaningless - how would you rate an F1 car for "Ride and Handling" ... or my classic Mini Cooper for that matter. Useless loonies.

  17. Kynetx Says:

    Thank you for writing this out. I've been railing against the priustocracy for years. People can only understand marketing and Toyota has done a brilliant job of marketing these byzantine heaps of over-engineered guilt-sinks in the U.S.
    I'd love to see a Prius with a 90-HP high tech diesel. That would probably get upwards or 65 MPG in mixed driving.
    My parents have long been coveting a Prius as their next commuter. I can't convince them to get a TDI of some kind or other because they once owned a notchback VW with an Aircooled pancake engine that was horribly unreliable.
    I managed to swindle an '85 300D Mercedes out of a dishonest dealer for actual market value and love it to death. No one has ever or since built cars like Mercedes. 4600 pounds of German steel, baby. 33 MPG in mixed spirited driving. I can actually wrench on it. Comfy and stylish.
    If Toyota would just bring back the EV Rav-4 I'd be all over it like bumper stickers on a Prius.

  18. mookers Says:

    VW does make some nice engines. I actually test drove a Jetta TDI and liked the engine and ride, but not the handling. Then I drove the Turbo FSI and LOVED the engine and handling, but not so much the ride. The ride notwithstanding, the hoon won out over the greenie. My excuse is that the TDI had an eight-month waiting list, and the Turbo FSI was available right now, in the colour I wanted. At least it still gives respectable economy... when I don't flog it. ;)

  19. Carnivean Says:

    Kynetx, (and others of course)

    The Prius engine achieves the same per joule efficiency as a diesel engine, and switching to a diesel engine would also provide more weight, and less perkiness from the engine. You could achieve nearly the same figures as a diesel hybrid by simply removing a lot of weight from the vehicle and using a turbodiesel.

  20. phrantic Says:

    Can all diesel vehicles benefit from the grease out of a Maccas fryer?

  21. Daniel Rutter Says:

    Huge commercial diesels like the ones in the Crawler Transporter may indeed run OK on vegetable oil; many giant diesels are made to run on cheap fuel oil, compared with which vegetable oil is lovely stuff (if a little lower in energy).

    Most modern automotive diesels are pretty fussy, though. They'll run fine on biodiesel, but not on SVO, at least not without major work.

    With a lot of diesels you can get away with mixing some vegetable oil in with your mineral diesel. More than a trivial amount, though, and you can be dicing with an engine rebuild, with a lot of modern cars.

    Those old Mercs, though, might well work on coal dust if you could find a way to get the fuel pump to move it :-).

  22. reyalp Says:

    I personally know a number of people using waste veg in fairly modern diesels (90s and up). These are running a heated tank, starting and shutting down on mineral diesel, and using good filtration. Even if you live in a warm climate the higher viscosity of room temp SVO seems to lead to coking.

    The golden fuel systems (formerly FAQ discusses this a bit. They obviously aren't a disinterested party, but it pretty much matches what I've heard from the people actually using the stuff. OTOH, there aren't nearly as many automotive diesels available here in the states, so it is certainly possible that some of the others have problems.

    There are also plenty of dissenting opinions.

    The cost of making a mistake is also obviously higher with a new car, not to mention the risk of voiding your warranty.

    I don't think I'd try it on a brand new car, at least not without very reliable reports from someone who had already done it. OTOH, given a 90s era TDI with a value of a few thousand dollars and reasonably plentiful junkyard parts, I wouldn't hesitate too much, on the understanding that there is some risk of having to replace the engine.

  23. loseweightslow Says:

    People that think RAV 4's or Prius' have anything other than good handling are the same kind of people that think iPods are crap because they dont play OGG. 99% of the market dont need or want better handling especially if the trade of is worse ride confort.

    I'd also like to point out that the Prius is a medium sized luxury car and any comparisions on price or fuel economy should be made on an equivalent basis to have any meaning.

  24. Rob L Says:

    Stastics show the 99% of clueless people like Prius, or Ssangyong, or are in Toyota marketing.

    If you knew anything about the car industry you would know that performance and handling is one of the BIG marketing points, just look at how wheels/tyres and brakes continue to grow. There's also the small point of passive safety, the chance of avoiding an accident in the first place. Look at how embarrassed Mercedes was when their new A class failed a handling test. Toyota have kept extremely quiet on just how poor the Prius is in this department.

    If people weren't interested in handling why would Porsche have made 2.1 BILLION EURO last financial year.

    How you can call the Prius a medium luxury car is ridiculous. A VW Jetta is practically line ball for interior space, $10k cheaper and just as fuel efficient in anything other than constant city driving. AND you won't have to replace a monsterous pack of enviro unfriendly batteries every five years.

  25. loseweightslow Says:

    Sexy women are also a big marketing point with cars and they dont even come with one. When it comes to handling, very few people care about it if the standard is as good as say a RAV 4. Mercedes wasn't embarrased about failing a handling test they were embarressed about failing a safety test. Wheel size is just is much about ride comfort and appearence, even saftey as handling. Brakes are about safety too.
    Porches profit says more about margins on prestige vehicles and current economic times than anyting about how handling sells cars. If I wait for a global recession and Porches profits fall I wont be arguing that this is proof that handling is irrelevent. The two are not connected.

    A little internet research shows me that the Jetta is only as fuel efficient as the Prius in continuous high speed highway driving. It gets comparatively worse the more city like the driving becomes. Not to mention that in Australia diesel is more expensive per litre and polutes more per litre than petrol. In pure enviro or fuel cost per km, the Prius wins. Diesel comes a close second.
    The prius is $9,000 more than the jetta but it does come with leather (what kind of luxury car comes with cloth seats?) Sat Nav and a killer sound system as extras. Delete thos features from the Prius and the difference is $1500, the Prius is an auto but the Jetta has a couple of extras (heated mirrors, dual zone instead of single). The Prius has a 5 star NCAP rating, the Jetta 4.

    The 5 year battery claim is rubbish. So is the enviro claim.
    The batteries have lasted over 350,000km's in a taxi and one engineer that looked at them said they would expect the batteries to last at least 15 years from new, probably a lot longer. There is a bounty on the batteries so they are recycled not thrown away.

  26. Rob L Says:

    Of the current crop of Aurion, Camry, Commodore, Falcon, 380, Corrola, Astra, Mazda 6 advertising I cannot think of ONE that features the "cool car, hot chicks" theme that you seem to imply drives the industry. There is however an awful lot of time devoted to showing how well these cars handle.

    RAV4 does not have good handling, it has at best average handling in that it will not try and kill you when you change lanes.

    Mercedes failed a handling test.

    Wheel size almost always degrades comfort due to less sidewall and higher unsprung mass. Demand for ride comfort has not driven an increase in wheel size ever.

    That conclusion is backed by no correlating data. Your personal predudices notwithstanding.

    That's what I said, diesel is better for highway, Prius wins in the city.

    More or less polluting depends on which metric you choose to look at. Over the vehicle life cycle the Prius scores poorly do to it's resource hungry manufacturing.

    As I look out my window diesel is 5c per litre cheaper than petrol. LPG is a third the cost of either.

    You stated the Prius was a medium luxury car, the comparison with a Jetta was simply to refute this, it is a small car, Compare it with a 307 diesel or an Astra. It is an expensive way to buy a small fuel efficient car. Add toys to taste if you wish.

    Claiming anything on the basis of taxi type use is pointless. Toyota acknowledges that if the Prius battery is not topped up every two weeks then it can degrade.

  27. loseweightslow Says:

    At the recent Sydney Motor show there was plenty of "cool car hot chicks" on show. You are correct that the hot chick method of selling has reduced significantly in recent times.

    If rolling over is a "handling" problem then I doubt I'll ever convince you of anything, but here goes. I did a little research on the A-class and here is what had to say: "Mercedes eventually solved the problem, but in the process it introduced severe understeer and a stiff ride to the A-class, ruining its original sweet driving manner. Still, once it restored customer confidence, some 1.1 million cars were sold."
    So, by giving the car worse handling, it made it safer and it sold well.

    What you say about larger wheel size on the same car is true. I was thinking of wheel size between generations of the same car. The Ford Falcon used to come with 14" rims. It now comes with 16" rims. The aspect ratio hasn't changed much resulting a larger radius tyre which does give better ride comfort, all other things being equal.

    I don't see how diesel wins for the highway with the same economy. Given that diesel has about 17% more CO2 emissions than petrol, I find it difficult to believe that the extra co2 used in creating the hybrid isn't made up for by the cleaner fuel over the lifetime of the car.

    Diesel may very well be cheaper at the one service station you sampled but the long term average difference is clearly in petrols favor.

    The Jetta is Mid size according to VW. "The quintessential VW mid-size sedan just got promoted"

    I notice you have gone from claiming that they need a new battery every 5 years to pointing out some degradation issue that most normal driving patterns will never see. Interestingly, I found a forum where a person claiming to be a veteran Toyota senior Product Specialist .He said "being mass produced since 1998, Toyota has NEVER had to replace even one battery due to failure, and many vehicles have over 250K mi." That comment was made in 05. 7 years, over 100,000 vehicles. The batteries are fine.

  28. sb Says:

    The Jetta is a compact car, also known as a small family car in Europe. see The VW Passat is their mid-size (EU "large family car") offering. The Polo and Golf small cars. The Toyota Prius is mid-size car (EU: "large family car").

    If you want to compare the Prius against anything, you can compare it against the Jetta or other small cars if you like, and the Prius will do quite well considering its a full car class bigger. But you're better off comparing it against other cars in its class, such as the passat, the ford taurus, the opel vectra, etc. assuming what you need a mid-size car, and your seeking to minimise the environmental damage of that. If you don't accept that, then compare a Jetta and a push-bike. Obviously the bike wins environmentally, but then it's not going to get you, your spouse and your 3 kids anywhere is it?

    So, if you want to use as little fuel as possible and be as green as you can drive the smallest car you can put up with. If you run it on diesel rather than petrol you'll be doing a good thing on balance. If you go for a small engine you'll be doing the right thing. If you can get a hybrid version of the car you need you'll be doing a good thing because hybrids have far far lower emissions while delivering the same and usually better fuel consumption under normal driving conditions, when comparing cars of the same class. That is all there is to it...Why is this issue one that creates such debate, with recycling of the same old arguments derived from a very few original and incorrect newspaper stories?

Leave a Reply