Fossil Fuels

A non-renewable energy resource

Outline

Extrapolating data.Modeling consumption and growth.Fossil Fuels

OriginsProductionUseFuture

Predicting the Future based on the Past.

The Second Law of Thermodynamics tells us that TIME always moves forward, to a point when energy is distributed more evenly and at a single temperature.So we can’t know the future!But since the way in which energy flows is governed by physical laws, can we observe what has happened in the past (data) and use those laws (analyze) to make predictions about the future?Let’s look at a simple example: Population.

World Population 1950-2000year population % growth

1950 2.56 billion 1.47

1960 3.04 billion 1.33

1970 3.70 billion 2.07

1980 4.45 billion 1.69

1990 5.28 billion 1.55

2000 6.07 billion 1.41

World Population

world population

01000000000200000000030000000004000000000500000000060000000007000000000

1940 1950 1960 1970 1980 1990 2000 2010

years

popu

lati

on

population

Looking into the future

There seems to be a trend upwards in world population.Assuming that this trend continues, we can try to predict the world’s population even 50 years from now. But which prediction is right?

The future world population?

world population

y = 3E-06e0.0176x

02000000000400000000060000000008000000000

10000000000120000000001400000000016000000000

1900 1950 2000 2050 2100

years

popu

lati

on populationExpon. (population)Expon. (population)

Exponential growth

Growth proportional to N . The rate of growth, r, is the percentage of N added to the total amount, per year.

Example: r = 2% growth per year means that .02 N is added to N every year.When N is big, exponential growth is fast!

N DOUBLES every DT = 70 ÷ r years.Example: r = 2% means that N doubles every 70/2 = 35 years.

Exponential growth of World Population?

Looking at our exponential curve for world population, we find

r = 1.76 %So, .0176 N is added to the population every year.N = 6 billion or 6 x 109, so 105 million people are being added per year.

DT = 70 / 1.76 = 40 years.In 40 years, the population will be 12 billion!Is it true?

US Census Bureau’s Prediction of World Population

world population

y = 0.0229e0.0131x

0

2000000000

4000000000

6000000000

8000000000

10000000000

12000000000

1900 1950 2000 2050 2100

years

popu

lati

on

populationExpon. (population)

US Census Bureau’s prediction, cont.

The curve doesn’t fit as well, because the growth rate is changing and probably will continue to change. The Census Bureau predicts a declining growth rate to less than 0.5 % by 2050 and a peak in population shortly thereafter.Exponential growth is NOT SUSTAINABLE over long periods of time.

Making friends exponentiallyDay Kate Anne Day Ann

e

1 2 1 11 512

2 4 2 12 1024

3 6 4 13 2048

4 8 8 14 4096

5 10 16 15 8192

6 12 32 16 ?

7 14 64

8 16 128

10 18 256

Non-renewable resources

There is a limited number of people at WIU. Exponential growth in friends quickly “consumes” all friend candidates.People can reproduce, but they depend on many non-renewable resources to survive. If population grows exponentially, consumption will also grow exponentially, and overwhelm the available resources.

Fossil FuelsExponential growth is a very POOR model for the consumption of non-renewable resources.M.K. Hubbert in 1957 made a startling prediction about the production of oil in the US. “Oil Production in the US will peak in 1967.”

Assumptions:• Oil is a finite resource.• Initially exponential growth in demand.• Eventual halt and decline in production as the resource

becomes more uneconomical to obtain.

The Bell-Curve

Our oil future?

Oil production in the US will essentially halt by 2040!Total oil produced is the AREA under the curve.