Date:         Wed, 4 May 2005 21:41:19 -0500
Reply-To:     Jim Felder <felder@KNOLOGY.NET>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Jim Felder <felder@KNOLOGY.NET>
Subject:      Re: gas mileage--existing cars kept running have a huge edge
In-Reply-To:  <Pine.LNX.4.61.0505042208030.425@donkeykong.gpcc.itd.umich.edu>
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I basically agree with you and somewhat with joy that it would be
difficult to assess how many BTUs goes into making a car but it is not
un-knowable.

And as far as the batteries go (Joy's post) I wasn't trying to compare
environmental impacts at all. I was mentioning that hybrid cars have an
additional impact, and did not make any speculation about a metric for
that impact. The batteries in those things will be replaced at least
once in 100K miles, I think, and they are toxic and heavy and take
quite a few BTUs themselves to manufacture. But I don't even know what
kinds of chemicals are in there. I have just read a few manufacturer's
concerns about it.

It's worth noting that the BTU make-from-new vs.
keep-the-old-one-running  comparison has a variable that is not
obvious, and that is the relative cleanliness of various manufacturing
technologies over time. If the cars in the future are made with cleaner
BTUs, then the gap between them and existing cars closes some. But a
BTU is a BTU, and you have to get the heat from somewhere, and I still
think that an existing car kept in good shape has a leg up on new
cars--however efficient--for a number of years or miles, and there is
no evidence I know of that the new car could ever catch up. No evidence
to the contrary, either.

Jim

On May 4, 2005, at 9:23 PM, Jonathan Farrugia wrote:

> joy is right life cycle assessment is difficult to do but its still a
> thing
> in my opinion that the amateur can play with and do almost as well as
> the
> researchers ;).  its really all about what metrics you choose in your
> analysis and how YOU weight the inter change between metrics in your
> model.  coming from an industrial background and having an
> "environmental
> sense" i often find that alot of the real "scientists" that i see play
> with life cycle analysis are pretty clueless about what it takes to
> make
> an industrial product and the practical aspects of how that product
> will be
> used by the masses.
>
> the best people i have seen to make a good stab at this are engineers
> that
> worked in their field then went back to school to get a phd in some
> type
> of environmental field.  a one person interdisciplinary approach i
> guess.
> then when they come out with a seemingly practical model they get
> heckled
> from both sides the policy flakes and the engineering at all costs
> people.
>
> to take this back towards vanagon content lets talk engine conversions.
> this doesn't come up much but was part of the attraction for me to do
> my
> engine conversion.  if you convert to most engines newer than the
> wasser
> boxer you will gain better emissions by rule of thumb.  also on the
> long
> term life cycle analysis bit if you select a engine that has a longer
> interval between rebuilds there is less "rebuilding" energy spend per
> engine life cycle.  as a side note many of us lament "throw away
> vehicles"
> but if you sit down and think about it as long as those vehicles are
> recycled and emissions go down over time that is a good way to ensure
> new
> cleaner technology adoption.
>
> jonathan
>