Wednesday, 23 September 2015

The VW "Scandal". Another non-story, brought to you by the Dead Tree press & the ever relevant BBC

Whereas I wouldn’t normally touch the BBC with somebody elses barge pole, they can be quite useful in finding out the opposite of what is actually true at any given moment & can usually (just about) be relied upon to sneak the truth in their articles somewhere down the bottom: 

It's all another blow for the diesel market

Certainly is. Over the last decade and more, carmakers have poured a fortune into the production of diesel vehicles - with the support of many governments - believing that they are better for the environment. Latest scientific evidence suggests that's not the case, and there are even moves to limit diesel cars in some cities.

It doesn’t take Sherlock Holmes to spot the dissembling weasel wording in that finely crafted piece of semantic yoga, does it?  

Personally, I’d like to see the “evidence” that ever suggested diesel might be “better” for “the environment” (human environment?  Animal environment?  Biodiversity? Polar bears / Penguins?  Sea levels?  Snails & crustaceans?) in the first place.  “Latest” of course could refer to evidence from 20 years ago if there has been nothing to the contrary in the meantime.  Certainly nothing has ever led me to seriously think that diesel might save the planet.  Try cycling on Londons streets & you will instantly know which of the two types of fuel are the most noxious.  Assuming that is, you are privileged enough to encounter one of the few remaining petrol vehicles that are still allowed in the capital.  Suffice to say, a few minutes behind one of the millions of black cabs or red buses will tell you all you need to know.

The competing technologies of "SI" (Spark Ignition) and "CI" (Compression Ignition) based engines have different merits & have jostled for position in various applications over the years.  

Without going into too much detail, the SI engines tend to use lighter, shorter chains of hydrocarbons, that tend to burn very fast, giving a good power to weight ratio which translates to good acceleration.  The thinner, more volatile fuels range from single carbon methane gas, or even zero carbon hydrogen right up to the various types of "petrol" or "gasoline" that are commonly graded by their "octane" value, where "octane" refers to hydrocarbons chains of eight carbon atoms.  

Compression Ignition engines do not require a spark & instead work by compressing a fuel air mixture to a much higher pressure at which point the mixture spontaneously explodes.  The additional work required to compress the mixture & the heavier engineering required means that these engines tend to have a lower power to weight ratio, which is compensated by using more energy dense fuel - typically diesel or fuel oil with an average chain length of 12 carbon atoms or more.  This most directly equates to a greater range for any given size of fuel tank.

The issues of economy and efficiency are much harder to quantify.  If the price were the same for both fuels, diesel / CI fuels would be more economical, but of course, consumer demand, supply availability and government subsidy are the dominant factors.  Efficiency is also much harder to quantify, as the petrol engines use a less energetic fuel and although the diesel engines have a much higher theoretical efficiency at the higher compression rates, it is questionable whether the extra weight & engineering outweighs this, especially within the range of parameters that consumers would consider desireable for driving on public roads.

What I'm getting at, is that even if there is anybody left out there with any remaining fucks to give about how much invisible, non-toxic plant food they are putting out on any given Tuesday, it is unlikely that there has ever been any evidence to suggest that a diesel vehicle is any more likely to emit less carbon than its petrol equivalent into the atmosphere for any given distance.  Therefore, there must be alternative reasons for the endless shoe / gourd waving.

I would like to offer an alternative historiography of the petrol-v-diesel debate over the years.  I’ll leave the reader to decide whether my version is more sanguine or more cynical…

Late 19th c – motor car that runs on petrol invented, striking a massive blow for Christendom against the various Eastern despotisms and satrapies & freeing us from the reliance of beasts of burden (human or otherwise) and making warfighting a whole lot more exciting.
Winner: Petrol assumes the mantle of Godfrey de Bouillon

Early 20th c – various mideastern states give up slave raiding W.Europe for the Hareems and Galleys & “let” us build loads of petrochem rigs to get all that slightly stickier, but still quite lovely oil out the ground to fuel our tanks & fight our glorious wars with.  Suddenly Diesel is king.  The Nazis didn’t have any of their own & had to figure out ways of breaking down the sticky stuff in coal.
Winner: Diesel drags the modernist ubermensch out of the darkness of superstition

1950s / 60s – turns out there's loads of really nice oil in the North sea.  (clue is in the name – Brent “light” crude)  and guess what – petrol is the greatest!  The American car industry reaches a peak of sorts, consolidating into the big brands, Chevy, Corvettey, Mustangy, Cadillac.  The Ford Cortina hits the UK.
Winner: Petrol liberates man and womankind - Burn Baby, Burn!

‘70s – OPEC collectively throw their toys out of the pram in a tantrum following an epic fail attempt to use all the lovely toys they bought from the Euros / US / USSR effectively against their Israeli cousins & decide they no longer wish to share their national treasure with us.  We decide that Western Civ is far too precious to risk wasting our own limited resources racing around Romford circuit on a Friday night & plump for a nice Volvo instead.
Winner: Back on the Diesel.

‘80s – Nah – actually ripping about in an XR3i is awesome.  Bring back the petrolheads…  Our French cousins, still nervous from the oil shocks of the 70s decide that les Nukes are also awesome & could be used to generate hydrogen / short chain fuels, but not the longer chain stuff very effectively.
Winner: Petrol is good

‘90s – Collapse of USSR & Marxian theory generally deprives the handwringing classes of any kind of effective means of beating their breasts about how our material comfort is built on the backs of crushing economic exploitation of the downtrodden masses of the world, so somebody comes up with the theory that all of our lovely progress is making the weather unbearable for everybody else so that they couldn’t possibly build half decent technologically advanced societies, thereby overturning millennia of received wisdom to come to the conclusion that not just Fire=Bad, but Fire=Very Very Bad.
Winner:  Nobody - the end is nigh...

‘00s – Oooh, it is quite warm isn’t it?  And some of those exotic Bedouin types that we get all our lovely hydrocarbons from have started flying planes into skyscrapers which isn’t on at all.  Somebody comes up with the genius idea that rather than buying all their hydrocarbons & selling them loads of carbohydrates in return (i.e. food – wheat, bread, pasta, etc) we could just turn the carbohydrates into hydrocarbons & sell them stuff to fight each other with.  Biodiesel rocks!  At the same time, however, it is being said that the good stuff is running out and it begins to look like the same guys who were in charge of totalling XR3i’s on the Gallows Corner flyover on the A12 in the ‘80s have now got their hands on the wheel of the economy, so it would be great if somebody could give it a bit of a “jump start” by investing in loads of awesome tech to develop dilithium crystals & building some really cool solar stuff & windmills to get free power out of the air and that?
Winner:  Diesel (and Kumbaya)

‘10s – The pearl-clutchers belatedly realise that the poor old Orang-utans have borne the brunt of their planet saving crusade.  Turns out that there is some kind of supply and demand thing that means people are going to chop down loads of forest to grow stuff if you suddenly tell them that you need loads of it really quick.  The anointed one brings peace and harmony to the M.E. nations who enthusiastically throw off their shackles & use their newfound freedoms to embrace their traditional values of poverty, chaos and barbarism.  All the neck slicing puts even the hardcore handwringers off their falafel, even to the point of boycotting petroleum products from the Mullahs who want to nuke the little stable in Bethlehem where our Dear Lord and Saviour lay down his sweet head in a manger two thousand years ago, although they are supposedly not on the same side as the neck slicers.  (who can tell, after all…?)  The internet finally breaks the stranglehold of the Honourable Society of Barons of the Dead Tree Press & it begins to dawn on people that the economy is pretty well FUBARred and that perhaps spanking the rest of our overdraft on Enron / Solyndra / Hanjin / Ningbo renewable lottery scratchcards wasn’t the best investment & that just maybe we should allow market forces back in.  This happily coincides with the discovery of shedloads of gas that can be frack'ed out of the ground.  It also coincides with the Russians embracing the virtues of the economic system formerly only promoted by the capitalist running dogs & exporting yet more voluminous quantities of light hydrocarbons.  Recent meetings even suggest that the resurgent unreconstructed Leftists under Comrade Corbyn may be seeking a rapprochement, or detente perhaps, with their former Soviet masters.  Therefore, at present Petrol / Gas / Light chain fueled SI engines are well and truly back in vogue
Winner: Petrol / Gas / Putinoff Vodka

The future...  Anybody care to speculate what might happen if the current conflagrations with our Russian neighbours continues to escalate to the point that they no longer want to sell us all their lovely light oil & gas products & we have to rely on the millions of years worth of sticky long chained coal that our island sits atop?

Personally, I'm giving serious consideration to ditching the pushbike & going for one of those single wheeled segway things.  If only they did a petrol powered version...

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