Environmental Engineering Reference
In-Depth Information
States, over 400 gallons (1514 litres) of oil per year are used to
feed each American. This figure does not include packaging,
refrigeration or transportation to retailers. How we are going to
feed seven billion people when oil production goes into permanent
decline? How we are going to maintain a society of megacities
and an oil-based automobile and aviation culture when oil prices
quadruple? These are the issues that will soon be at the top of
the political agenda.
Once the reality of the crisis hits home, there will be a desperate
attempt to develop alternatives to oil, but probably coming much
too late to avoid a long term crisis due to faulty economic models,
a failure to head warnings from the scientific community and a
lack of preparation.
1.
Energy Alternatives
What about coal, nuclear, solar, wind, hydro, geothermal, biogas,
wave energy, hydrogen-based fuel cells and other energy techno-
logies? Can they not replace oil so we can continue our high
consumption society? Leaving aside for the time being the problem
of ecosystem overload, none of these can replace oil. They are all
substitutes in the sense that they are types of energy, but none has
the low cost access or concentrated energy of oil that has allowed
us to build up a highly technological, centralised, automobile-based
society. In the future, when considering alternative strategies, we
will have to think much more in energy terms rather than economic
calculations based on distorted pricing.
The key question we have to keep asking regarding useful
energy production is, how much energy do we put in and how much
do we get out? It costs energy to produce usable energy. The source
has to be mined, the raw product refined and transported before it
can be used usefully at the point of need. Table 1.1 shows roughly
how much energy we can usefully get out of various energy sources
for one unit of energy put into production, the so-called EROEI
(Energy Return on Energy Invested): A figure less than 1 means
that we use more energy on the input side than we get on the
output side. Figures are based heavily on the analyses of Charles A.
S. Hall, systems ecologist and professor at the State University of
New York [5].
Search WWH ::




Custom Search