I recently sent an e-mail to the Bundesbahn asking why they used the term
"kph" rather than "km/h" on their English-language website.  It appears that
they are pandering to the lowest level of British intelligence.

 

  _____  

From: owner-u...@colostate.edu [mailto:owner-u...@colostate.edu] On Behalf
Of Pat Naughtin
Sent: 01 January 2011 00:36
To: U.S. Metric Association
Cc: USMA Metric Association
Subject: [USMA:49368] High speed rail error

 

Dear Carleton,

 

I think you will be interested in this train story at
http://www.cahsrblog.com/2010/12/hsr-emissions-paper-was-wrong/?utm_source=r
ss
<http://www.cahsrblog.com/2010/12/hsr-emissions-paper-was-wrong/?utm_source=
rss&utm_medium=rss&utm_campaign=hsr-emissions-paper-was-wrong>
&utm_medium=rss&utm_campaign=hsr-emissions-paper-was-wrong where they say:

 

Berkeley's numbers are undone by a simple unit conversion error committed by
a CHSRA consultant. Conversions between metric and imperial units are prone
to errors and misunderstandings, most famously in the case of NASA's $300
million Mars Climate Orbiter mission, which was inadvertently
<http://en.wikipedia.org/wiki/Mars_Climate_Orbiter#The_metric.2FUS_customary
_units_mix-up> crashed into Mars because of an overlooked conversion between
pounds and Newtons. In the case of the high-speed rail study, the CHSRA
consultant's unit conversion error leads to an overestimate of HSR energy
consumption by a factor of nearly four-not just in the Berkeley study, but
also in the CHSRA's program level environmental reports.

The energy consumption figure cited in the
<http://iopscience.iop.org/1748-9326/5/1/014003/pdf/1748-9326_5_1_014003.pdf
> Berkeley study and its
<http://iopscience.iop.org/1748-9326/5/1/014003/media/erl10_1_014003supp.pdf
> supplementary data is 170 kilowatt-hours per vehicle kilometer traveled,
or kWh/VKT, a measure of how much energy a high-speed train consumes on
average when traveling one kilometer. This number is correctly converted by
Berkeley from a figure of 924,384 BTU/VMT referenced in the
<http://cahighspeedrail.ca.gov/WorkArea/DownloadAsset.aspx?id=1321> energy
chapter of the 2008 CHSRA program-level EIR. That chapter in turn references
a peer-review study performed for CHSRA by the German firm DE-Consult in
2000, which evaluated the energy consumption of a hypothetical 16-car
trainset with a seating capacity of 1200 and a design speed of 385 km/h (240
mph) and an operating speed of 350 km/h (220 mph), essentially a souped-up
<http://en.wikipedia.org/wiki/ICE3> German ICE3. The DE-Consult study
(unavailable online) contains detailed performance simulations for the
proposed California system that give the average energy consumption of such
a train as 74.2 kWh/VMT, or 46 kWh/VKT (see
<http://www.tillier.net/stuff/hsr/de_consult_numbers.png> copy of Annex
4-11). And therein lies the error: CHSRA's consultant botched the conversion
from kilowatt-hours to British Thermal Units, feeding Berkeley a figure of
170 kWh/VKT instead of 46 kWh/VKT.

I wonder why they were converting from British Thermal Units (no temperature
specified) to kilowatt hours instead of (say) megajoules per kilometre
(MJ/km). Clearly none of the consultant engineers has any sort of firm grasp
on metrology -- VKT for vehicle kilometre travelled doesn't impress me as
coming from a knowledgeable person who knows his SI from his toothbrush.

 

Cheers,

 

Pat Naughtin LCAMS

Author of the ebook, Metrication Leaders Guide, see
http://metricationmatters.com/MetricationLeadersGuideInfo.html

Hear Pat speak at: http://www.youtube.com/watch?v=_lshRAPvPZY 

PO Box 305 Belmont 3216,

Geelong, Australia

Phone: 61 3 5241 2008

 

Metric system consultant, writer, and speaker, Pat Naughtin, has helped
thousands of people and hundreds of companies upgrade to the modern metric
system smoothly, quickly, and so economically that they now save thousands
each year when buying, processing, or selling for their businesses. Pat
provides services and resources for many different trades, crafts, and
professions for commercial, industrial and government metrication leaders in
Asia, Europe, and in the USA. Pat's clients include the Australian
Government, Google, NASA, NIST, and the metric associations of Canada, the
UK, and the USA. See http://www.metricationmatters.com
<http://www.metricationmatters.com/>  for more metrication information,
contact Pat at pat.naugh...@metricationmatters.com or to get the free
'Metrication matters' newsletter go to:
http://www.metricationmatters.com/newsletter to subscribe.

 

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