Re: World's Largest Conveyor Belt

Mark eloquently commented in misc.writing:

I wrote:
Coal has a heating value of about 3,645 watt-hours/pound. That
means a typical 100 watt light bulb should burn about one hour per day
for an entire year on 10 pounds of coal.

The program was "Frontline", one of the most credible
news sources in existence today.

Frontline makes mistakes, but not ones that egregious.

And I believe the 10lbs of coal to one hour of (incandescent)
lightbulb, is very much like filling up your automobile with
gasoline, and trying to compare the energy value of
petroleum vs. the theoretical energy to accelerate the
corresponding mass.

Pfui.
I used to do this stuff for a living but just to be sure, I
consulted with my friend, "Bob." Bob really did this stuff for
breakfast as a Distinguished Engineer for one of the big chemical
companies. Here's his response:

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Typical --- "I saw it on PBS so I am right."

You [meaning me] did forget that the
generation/distribution efficiency is about
33% (mostly Rankine cycle thermodynamic
losses.... all that heat to the cooling tower.)
But you are a LOT more orders of magnitude
right than he is.
----------

Exactly.
I have to admit that I ignored any losses in the system by
pretending that we could squeeze that coal and simply pour the
electricity directly into the light bulb but even in the worst case,
our 10 pound rock is good for a month of light rather than a year.
And that is rather the point, innit.
Here we have an example (10 pounds = 1 hour) that is not just
bad science but one that is intuitively obvious that it is bad
science. However, comma, because it came from an authoritative source
(PBS) it must be OK.
Here's another, similar, example:

----------
A small study conducted by the University of
Washington and the Seattle Children?s Hospital
Research Institute showed that exposure to
phthalates caused reproductive problems in mice.

"If it?s difficult to say and it?s not commonly known,
it?s probably something we should wonder about,"
Dr. Lori Racha of University Pediatrics told the local
television news program(1).
----------

Hello?
"If it?s difficult to say"???
This is a gen-you-wine medical doctor who wants us to make a
crucial decision based on what she DOESN'T KNOW.
I'm thinking if something sounds wrong, taking it on faith is
a bad plan. And maybe, just maybe, if it's something that we don't
know the answer to, we should do what reporters are supposed to do.
That would be legitimate fact checking.

--***

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(1) Find this and other examples here:
http://blog.dickharper.com/category/science-not-so-real/
.

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