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Re: Yuri receives hypocrite of the week award (was Re: Ecological Economics and Entropy)





David Lloyd-Jones <dlj@inforamp.net> wrote in article 


> >
> >Of course if the earth's population is not controlled at the 10-12
billion
> >level, the only effective way to 'house' these billions is high density
> >cities.  But such beasts are huge ENERGY sinks.  
>  
> How do you figger?  My impression is that cities have been sources of
> energy for most of history; in the current generation the, uh, current
> generation has moved to the suburbs.  Still you will find that the
> wires generally carry the power _from_ cities where it is generated to
> everywhere else.
>  
> Cities of course import coal, oil, gas, and now uranium and plutonium
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> -- but they export the thought to pay for them, as well as the energy
> generated from them.
>  

> 

But this is just the point--I'm talking ONLY about the energy resources
(the kinds measured in Joules, BTUs, or kilowatt hours) necessary to
sustain the society.  Everybody, whether rural or city, requires a certain
amount to maintain their lives, but it will be 'more' possible in the
future to supply rural populations with dispersed, renewable, energy
sources.  For example, if cost is not a factor, you can set up
photovoltaics with battery storage today and be energy self-sufficient--for
a separate house with only a little land.  However, consider a high-rise
with maybe 1000 people living within.  That building does not occupy enough
space to be self-sufficient.  The energy source must be external.  Thus the
coal, oil, gas, and or nuclear power plants are necessary to run the high
rise.  Put a bunch of high rises together with stores, factories, office
buildings and put those all as close together as you can--and you have
yourself a city--which sucks energy from any supply system.  You do gain
certain efficiencies with close packing the population and reducing
transportation costs, but for the solar/wind proponents, cities are a
problem because of the energy densities needed.  Lots of energy in one
place.

Cities have NEVER been a source of this kind of energy.  The source IS
coal, oil, natural gas, a little hydro and a little nuclear.  Cities don't
generate any of this--they use it (as does all of civilization).  The
problem of course is that if we continue to use fossil fuels for the needed
energy we must contend with the local polution problems plus the
'possibilty' of more global effects (see the global warming debates that go
on ad-nauseum on these lists).  Mankind has already tapped almost 50% of
the readily available hydro power (which amounts to less than 3% of world
energy use anyway), and while nuclear has many advantages (such as high
production density, no greenhouse worries) it also has problems (public
perception, waste disposal uncertainties, accident possibilities, and is
still a finite source without breeder technology, and also provides only 3%
of world energy supplies currently).  If solar and wind are to be major
players in the future, they first must be scaled up by enormous factors
(being less than 1% of world supplies today), must be affordable, and must
satisfy the energy density demands of cities.  Powering the U.S. northeast
with wind and/or solar is no mean task.

So, large human populations will demand (without whole new social and
economic models) large cities, which ARE major headaches for energy
planners.  Of course cities have lots of other problems peripherally
related to energy (such as water supplies, sewage handling, food and
services distribution systems, etc., etc.)  Again, one CAN be
self-sufficient on a small rural farm--one cannot be in a city.

> Your "sink" idea rather reminds me of the idea that the countryside
> supports the cities, which is of course not true.  Famines always
> happen worst in rural areas; cities can buy food anywhere.  It is the
> cities which provide the rural areas with the income they need to buy
> the necessities -- energy, clothing, manufactured goods.  Food?  Hell,
> anywhere there's sunlight or salt water.

How much food is grown in Manhattan?  Haven't seen many dairy farms in
downtown Chicago.  Phoenix's water supplies?  Coal mines, iron mines, in
downtown Pittsburgh?  Sorry--the raw materials, the FOOD, and often even
the water that supports cities comes from the rural surroundings (not the
suburbs which are only slightly less dense cities)--and certainly the
energy resources as well.

Rick Tarara




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