Lecture II.

EXPONENTIAL GROWTH

The basic reason that we have a problem is due to exponential growth which creates a strongly non-equilbrium use of our resources.

Its not to great of simplification to state that the failure to understand the concept of exponential growth by planners and/or legislators, is the single biggest problem in all of Environmental Studies and/or Management.

The Two Principle Problems with Energy Management:

Exponential growth drives resource usage for a very simple reason:

Human population increases exponentially:

Accurate trend extrapolation is the most important part of future planning. However, failure to assume exponential growth will always lead to a disaster so always assume exponential growth when planning anything!

In this example, one can clearly see that no matter what the growth rate is, exponential growth stars out being in a period of slow growth and then quickly changes over to rapid growth with a characteristic doubling time of

70/n years; n =% growth rate

Its important to recognize that even in the slow growth period, the use of the resource is exponential. If you fail to realize that, you will run out of the resource pretty fast:

Material Rate Exhaustion Timescale
Aluminum 6.4% 2007 -- 2023
Coal 4.1% 2092 -- 2106
Cooper 4.6% 2001 -- 2020
Petroleum 3.9% 1997 -- 2017
Silver 2.7% 1989 -- 1997

The above estimates include recycling.

ENERGY CONSERVATION

Gasoline is a prime example high cost promotes conservation/ fuel efficiency; low cost promotes high usage.

Subsidized energy usage also does not promote conservation


Saving the Earth via choice of light bulb

Now lets calculate the total cost over the lifetime of the fluorescent bulb assuming a cost rate of 10 cents per KWH.

So, over a 10,000 hour period, the fluorescent bulb has a total cost of $30 and the Incands have a total cost of $82.50.

You just saved 50 bucks as well as 600 KWH of energy.

Clearly always use fluorescent bulbs if you are interested in saving energy and money.

What areas are good for conservation?

Where can the individual home owner conserve?

Energy Costs and Appliance Usage

Note, the applet below will only work if you are using IE 4.0 or Netscape 4.04. If not, the applet will come up broken.

How much do your appliances cost you? In this applet you will have an opportunity to compare the yearly energy costs for various appliances depending upon their rate of usage.

This applet works as follows:

  • Enter in the cost per kilowatt hour (the default is 10 cents).
  • Select an appliance from the icon list by clicking on it
  • Enter in the number of hours per day to use it (if you use say your dryer for an hour say once every two days then enter in 0.5 here)
  • Click the add to list button when done
  • A running sum will be kept
  • If you want to see how much an individual appliance in the list costs per year, then just click on that item in the list.
  • To remove an item click on the remove from list button.

As an initial exercise, enter in 15 cents per kilowatt hour for the rate and then see if you can construct a pattern of appliance usage so the total yearly cost does not exceed $2000.

Saving energy in the Transportation Sector:

Options:

  • Mass Transit
  • Work close to Home
  • Work in Home
  • Better fuel efficiency
  • Alternative Fuels/power
  • Tax Gasoline

The true cost of our private conveyance habit: The cost of this habit is extremely large when objectively looked at.

    Major cause of air pollution which is a health hazard that kills people!

    We export billions of dollars of US currency overseas for fuel and then evolve a foreign policy to protect that this is beyond stupid ...

    We consume lots of resources (steel) via the relatively short lifetime of a basic non-recyclable unit. Automobiles basically serve to transport iron ore from omuntains into distributed junk yards across the US (entropy at work ...)

    40,000 people per year are killed in accidents compared to 500 per year in mass transit.

    Infrastructure and maintenance costs are absolutely enormous where is high speed rail when you need it ...

    Everyone's has got to park (except at the UO) so we convert green space into parking lots (e.g. malls).

    We end up with Grid Lock

    Only in World War II was there an agressive public relations campaign to get people to drive less. It worked. Here is some propaganda from that era.

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