Re: Global Energy etc.

[Rick Tarara <rbtarara@SPRYNET.COM>]

----- Original Message -----
From: "Daniel Schroeder" <DSCHROEDER@CC.WEBER.EDU>
> But I never suggested that wind could provide all our electricity.
> What would you consider a "sizeable" percentage, anyway?  In the U.S.
> we currently get 11% of our electricity from hydroelectricity and
> 20% from nuclear energy.  For wind power to reach these levels
> we would need a few hundred thousand turbines--a large number,
> to be sure, but not unthinkable.
>
> Dan

Each year I have my class do a project where they try to design an energy
system for the year 2100.  We make a number of assumptions such as a
population of 450,000,000 and a per capita energy consumption similar to
today (which they then can reduce through conservation and efficiency--but
need to do the numbers to show just how much energy can be saved without
unduly effecting our life style).  I allow for the continued use of coal but
eliminate oil and natural gas by this time.  The mix then must be coal,
solar, wind, nuclear, geothermal, and biomass.  We don't count unhatched, so
fusion is not allowed.  With this mix, wind may have to account for 20-25%
of the TOTAL energy needs.  For the units chosen with reasonable assumptions
on average power output, we usually get 5-6 million windmills, 10s of
thousands of square miles of land (with some dual usage allowed) and a cost
of several trillion dollars.  Last year as I remember the _total_ project
estimated the cost at 12 trillion dollars and close to 175,000 square miles.
We had 25% coal, 5% geothermal, 10% biomass, 20% nuclear, 20% solar, and 20%
wind in the mix and they tried to reduce energy use 25% but only could
justify 20%.  All of this is very crude and the class is the liberal arts
general education class so I have to help a lot with the calculations, but
it does give them a feeling for the magnitude of the task of weaning
ourselves from the fossil fuels.

The big factor here is that the world MUST (sooner or later) stop using
fossil fuels (they'll run out or be environmentally TOO destructive) so we
have to look at providing ALL the energy needs with the kinds of resources
listed above.

[BTW: I use the yearly energy table published in the Encyclopedia Britannica
yearbooks for all the countries in the world that detail energy production,
reserves, and usage--converting everything to kWh--for my stats.  Total
electrical usage is given with the amount of hydro, nuclear, and geothermal.
I then just total the coal, oil, gas, nuke, hydro, and geo usage to get
totals--so I don't adjust as you did for the conversion of fossil to
electricity.]

Rick

**************************************************
Richard W. Tarara
Associate Professor of Physics
Department of Chemistry & Physics
Saint Mary's College
Notre Dame, IN 46556
219-284-4664
rtarara@saintmarys.edu

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