Energy/Power dilemma:
This lack of distinction between the two quantities
contributes to keeping the masses in the dark on energy issues. The pro-green
magazines are notorious for mixing those terms; sometimes to their advantage but
mostly just proving they do not know what they are talking about. MIT's own
Technology Review magazine has had these terms mixed, even with units
included (SI or non-SI). If MIT does it, what chance is there anyone else will
be careful (or educated) enough?
In my training classes, I go into this topic with
practical exercises, the depth of which is tailored to the educational level and
needs, of course. In my writing to the editors very few times I scored
being published.
The way to approach it best, in my opinion, is by
training educational text book writers and teachers. Neither group is
particularly easy to get to listen.
Stan Jakuba
----- Original Message -----
Sent: 05 Oct 22, Saturday 03:39
Subject: [USMA:34965] Energy or
power
Dear
All,
Recently, I was reading Paul Roberts' book, 'The End of Oil' when
I came across this paragraph:
More broadly, this trend helps us see why energy
experts get so anxious when they begin calculating how the world is going to
power itself over the next century. By most estimates, assuming that
projections for future energy demand and population growth hold true - and
that we maintain our current disdain for energy efficiency - by the year
2100, the world's ten billion people will need something on the order of
fifty terawatts of electricity, or around four times what we produce today.
That is a staggering amount of power. Generating it would require an energy
infrastructure far larger and costlier than any that exists today, and it
raises questions about not only the adequacy of our energy supplies, but the
quality of that energy. By some estimates, given the slow success and low
power densities of nonhydrocarbon energy technologies, we would not be able
to meet all this new demand without using a lot of fossil fuels, which we've
no way to ensure that we can burn cleanly. In other words, our unwillingness
to take energy efficiency seriously enough to reduce demand may make it
flat-out impossible to stay within any sort of reasonable carbon budget.
The End of Oil, Paul Roberts, Mariner Books
2005, p 223
In this single paragraph Roberts uses the word,
'energy' 8 times, and the word 'power' 3 times. Each time he used either of
these words, I had to stop reading to decide whether he used these words
correctly or, as is so common in everyday media stories, as though energy and
power were interchangeable words with the same meaning.
To a
metrologist, a physicist, or an engineer energy and power are quite different
quantities altogether and they shouldn't be muddled. As these folk
know:
energy is the ability to do work and it is measured in joules,
and
power is the rate at which energy is used and it is measured in
watts.
My concern over this apparently simple matter is that books like
Paul Roberts' are beginning to be debated all around the world and many
commentators are not at all clear what energy and power are and how they
differ from each other.
Can anyone tell me how they approach this
measurement dilemma?
Cheers and thanks,
Pat Naughtin
Geelong,
Australia
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