There are three papers by Sterman and Richardson (last two also by
Davidsen) on the dynamics of U.S. and global estimates of the the peak in
oil production and the ultimate recoverable reserves. The analogy method
of the U.S. Geological Survey is almost certain to overshoot the true
ultimate recoverabel resource.
Sterman & Richardson. An Experiment to Evaluate Methods for Estimating
Fossil Fuel Resrouces. Journal of Forecasting, 4 (1985): 197-226.
Sterman, Richardson, and Davidsen. Modeling the Estimate of Petroleum
Resources in the United States. Technological Forecasting and Social
Change, 33 (1988): 219-249.
Davidsen, Sterman, and Richardson. A Petroleum Lifecycle Model for the
United States with Endogenous Technology, Exploration, Discovery,
Recovery, and Demand. System Dynamics Review 6,1 (Winter 1990).
...GPR
----------------------------------------------------------------------
George P. Richardson G.P.Richardson@Albany.edu
Associate professor of public adm., public policy, and info. science
Rockefeller College of Public Affairs and Policy Phone: 518-442-3859
University at Albany - SUNY, Albany, NY 12222 Fax: 518-442-3398
-----------------------------------------------------------------------
oil and gas prices and reserves
-
- Senior Member
- Posts: 68
- Joined: Fri Mar 29, 2002 3:39 am
-
- Member
- Posts: 21
- Joined: Fri Mar 29, 2002 3:39 am
oil and gas prices and reserves
Thomas Fiddaman wrote:
>
> To replace 1990 oil consumption with horses, youd need about 6 billion of them:
> snip
of course, as the Romans understood, the fuel efficiency of a horse
and human laborer are not that different, so much of the work done by
fossil fuels (e.g., moving people or packages short distances) would
be done by people, not horses.
> Of course, this is a silly calculation, as you dont need 200 horses to get
> to work, though many car owners seem to think that they do. For
> space-heating applications, smaller animals like pigs or chickens might be
> more convenient.
...also lighting and cooking. in rural China, some small farmers
homes are built with an attached enclosed pig "barn" over a buried concrete
box which digests the manure. the resulting methane output is piped
into the home for light and cooking.
William Steinhurst
wsteinhu@psd.state.vt.us
>
> To replace 1990 oil consumption with horses, youd need about 6 billion of them:
> snip
of course, as the Romans understood, the fuel efficiency of a horse
and human laborer are not that different, so much of the work done by
fossil fuels (e.g., moving people or packages short distances) would
be done by people, not horses.
> Of course, this is a silly calculation, as you dont need 200 horses to get
> to work, though many car owners seem to think that they do. For
> space-heating applications, smaller animals like pigs or chickens might be
> more convenient.
...also lighting and cooking. in rural China, some small farmers
homes are built with an attached enclosed pig "barn" over a buried concrete
box which digests the manure. the resulting methane output is piped
into the home for light and cooking.
William Steinhurst
wsteinhu@psd.state.vt.us
-
- Junior Member
- Posts: 5
- Joined: Fri Mar 29, 2002 3:39 am
oil and gas prices and reserves
In a letter to the editor of the Portland Oregonian, on 12/9/96.
Jim Craig of the American Petroleum Institute says:
"Sachs incorrectly reports "most of the worlds known oil reserves will be
used up in 10 years", ... Let me cite the highly regarded U.S. Geological
Survey, which estimates that between 1.4 trillion and 2.1 trillion barrels
of oil remain to be produced worldwide (one barrel is equal to 42 gallons.
"This estimate would sustain current consumption rates between 63 and 96
years. In other words, theres a 95 percent possibility that the worlds
remaining oil reserves could last 63 more years, and a 5 percent chance
that the global resources will last another 95 years based on recent
consumption."
Does anyone see a problem here that might be eluding Mr. Craig?
1. I agree that Mr. Sachs estimate is probably overly pessimistic.
2. Mr. Craig seems to be saying, "What, me worry?" I wonder if he grew up
reading Mad Magazine like I did?
3. Maybe someone with a population dynamics background could develop a
model describing how long it will take to grow a large enough population of
horses to take up the slack, to be ready for service somewhere between 63
and 95 years in the future. And of course we will need saddles, livery
stables, oats, etc. to provide additional infrastructure.
Also on 12/6/96 SD MailList, Bob Powell quoted Peter Senge:
" Peter Senge said at the 1996 Power of Systems Thinking
conference: "Why isnt system dynamics spreading like wildfire? We live in
institutions whose fundamental way of being is antithetical to the tools ...
other than that no big problem."
Could we find a more cogent (tragic) example than Mr. Craig? I cant think
of one.
Ed Gallaher, Ph.D.
Assoc. Professor, Physiology/Pharmacology
and Behavioral Neuroscience
Oregon Health Sciences University
Portland, OR
Jim Craig of the American Petroleum Institute says:
"Sachs incorrectly reports "most of the worlds known oil reserves will be
used up in 10 years", ... Let me cite the highly regarded U.S. Geological
Survey, which estimates that between 1.4 trillion and 2.1 trillion barrels
of oil remain to be produced worldwide (one barrel is equal to 42 gallons.
"This estimate would sustain current consumption rates between 63 and 96
years. In other words, theres a 95 percent possibility that the worlds
remaining oil reserves could last 63 more years, and a 5 percent chance
that the global resources will last another 95 years based on recent
consumption."
Does anyone see a problem here that might be eluding Mr. Craig?
1. I agree that Mr. Sachs estimate is probably overly pessimistic.
2. Mr. Craig seems to be saying, "What, me worry?" I wonder if he grew up
reading Mad Magazine like I did?
3. Maybe someone with a population dynamics background could develop a
model describing how long it will take to grow a large enough population of
horses to take up the slack, to be ready for service somewhere between 63
and 95 years in the future. And of course we will need saddles, livery
stables, oats, etc. to provide additional infrastructure.
Also on 12/6/96 SD MailList, Bob Powell quoted Peter Senge:
" Peter Senge said at the 1996 Power of Systems Thinking
conference: "Why isnt system dynamics spreading like wildfire? We live in
institutions whose fundamental way of being is antithetical to the tools ...
other than that no big problem."
Could we find a more cogent (tragic) example than Mr. Craig? I cant think
of one.
Ed Gallaher, Ph.D.
Assoc. Professor, Physiology/Pharmacology
and Behavioral Neuroscience
Oregon Health Sciences University
Portland, OR
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oil and gas prices and reserves
Ed Gallaher, Ph.D. quoted Jim Craig:
"Sachs incorrectly reports "most of the worlds known oil reserves will be
used up in 10 years", ...
Does anyone see a problem here that might be eluding Mr. Craig?
There is a zero percent chance that consumption will remain the same.
The International Energy Agency projects that world oil demand will
rise from the current 68 million barrels per day to around 76 million
b/d in year 2000 and 94 million b/d in 2010.
In March of this year, World Resources Institute published a report
that stated:
"Two important conclusions emerge from this discussion. First,
if growth in world demand continues at a modest 2 percent per
year, production could begin declining as soon as the year 2000.
Second, even enormous (and unlikely) increases in [estimated
ultimately recoverable] oil buy the world little more than
another decade (from 2007 to 2018). In short, unless growth in
world oil demand is sharply lower than generally projected,
world oil production will probably begin its long-term decline
soon, and certainly within the next two decades."
The entire report is online at:
http://www.wri.org/wri/energy/jm_oil/index.html
Jay -- http://csf.Colorado.EDU/authors/hanson/
jhanson@ilhawaii.net
"Sachs incorrectly reports "most of the worlds known oil reserves will be
used up in 10 years", ...
Does anyone see a problem here that might be eluding Mr. Craig?
There is a zero percent chance that consumption will remain the same.
The International Energy Agency projects that world oil demand will
rise from the current 68 million barrels per day to around 76 million
b/d in year 2000 and 94 million b/d in 2010.
In March of this year, World Resources Institute published a report
that stated:
"Two important conclusions emerge from this discussion. First,
if growth in world demand continues at a modest 2 percent per
year, production could begin declining as soon as the year 2000.
Second, even enormous (and unlikely) increases in [estimated
ultimately recoverable] oil buy the world little more than
another decade (from 2007 to 2018). In short, unless growth in
world oil demand is sharply lower than generally projected,
world oil production will probably begin its long-term decline
soon, and certainly within the next two decades."
The entire report is online at:
http://www.wri.org/wri/energy/jm_oil/index.html
Jay -- http://csf.Colorado.EDU/authors/hanson/
jhanson@ilhawaii.net
-
- Member
- Posts: 33
- Joined: Fri Mar 29, 2002 3:39 am
oil and gas prices and reserves
Although the timing for the peaking of production is probably as accurate
as these things get, it may be premature to declare the end of the world
and focus on the lack of system thinking about finite resource bases as
its own topic. Conventional production extracts, in general, only 15% to
25% of the resources in place. Advanced enhanced recover (including some
new bioengineered products) can do much better -- as much as 60% recovery.
Not all fields can achieve this recovery in secondary and tertiary efforts
but assuming an unchanging world is a limited view. Price may have to rise
significantly for high recovery (of old fields) to be common place and
social trauma may even ensure due to myopic industry responses combined
with real development timing problems (the actual area where SD helps out
the logic). We also should not forget Canadian tar sands - no small
resource and currently produced at $8/bbl (but with significant
environmental issues). With brief (decade) excursions into intense natural
gas use and synthetic oil from coal, other long-term options still remain
to replace oil in its transportation, lubrication and manufacturing
(plastic) uses. The end point of rapidly declining oil production is a
nice analysis, but the real social issue is how to make the transition
without messing up too many lives. The D in SD is for dynamics. If we have
the religious view that SD can help society, than our focus, it would seem,
should be on helping society survive the dynamics that the course of
history continuously provides. This is later perspective is "systems
thinking" - not the timing of one component of the system - oil production.
George Backus
Policy Assessment Corporation
gbackus@boulder.earthnet.net
as these things get, it may be premature to declare the end of the world
and focus on the lack of system thinking about finite resource bases as
its own topic. Conventional production extracts, in general, only 15% to
25% of the resources in place. Advanced enhanced recover (including some
new bioengineered products) can do much better -- as much as 60% recovery.
Not all fields can achieve this recovery in secondary and tertiary efforts
but assuming an unchanging world is a limited view. Price may have to rise
significantly for high recovery (of old fields) to be common place and
social trauma may even ensure due to myopic industry responses combined
with real development timing problems (the actual area where SD helps out
the logic). We also should not forget Canadian tar sands - no small
resource and currently produced at $8/bbl (but with significant
environmental issues). With brief (decade) excursions into intense natural
gas use and synthetic oil from coal, other long-term options still remain
to replace oil in its transportation, lubrication and manufacturing
(plastic) uses. The end point of rapidly declining oil production is a
nice analysis, but the real social issue is how to make the transition
without messing up too many lives. The D in SD is for dynamics. If we have
the religious view that SD can help society, than our focus, it would seem,
should be on helping society survive the dynamics that the course of
history continuously provides. This is later perspective is "systems
thinking" - not the timing of one component of the system - oil production.
George Backus
Policy Assessment Corporation
gbackus@boulder.earthnet.net
-
- Senior Member
- Posts: 54
- Joined: Fri Mar 29, 2002 3:39 am
oil and gas prices and reserves
As oil imports in the US reach and exceed 50%, and as volatility returns
to the oil market, the topic of petroleum depletion is being
rediscovered.
The history of attempts to gauge the size of the petroleum resource base
is an interesting and contentious one. A few years ago, George
Richardson, Pal Davidson, and I developed system dynamics models of the
dynamics of estimates of world and US petroleum resources. The focus
was the accuracy over time of the estimation procedures used by various
groups (the USGS, oil cos, etc.) to guess at how much oil there is, and
how much is likely to be recoverable.
It is obvious that natures initial endowment of oil to humanity (known
as initial oil-in-place) is fixed relative to the human time scale (that
is, petroleum is formed over geologic time while consumed over only a
few hundred years, so relative to our time horizon, the petroleum
creation rate is essentially zero). It is also obvious that the amount
of oil remaining in the ground to be consumed in the future is
monotonically declining.
*Estimates* of initial oil in place, however, can rise or fall as
knowledge, opinions, methods, and political pressures change. There are
a variety of estimation methods. One of the most popular is the
"geologic analogy method" in which the abundance of oil in unexplored
regions is estimated by assuming it will be similar to that in known
regions of similar geology. Historically, as each region is opened to
exploration, the estimates start low, then rise rapidly as greater
exploration and improved geological knowledge lead to better estimates.
But instead of flattening out close to or asymptotically approaching the
"true" level, estimates in the US dramatically overshot and then
collapsed. In the 1960s the USGS estimated the ultimate recoverable
petroleum resource base to be nearly three times as great as the value
now widely accepted and endorsed by USGS. Why the overshoot? The
models we developed explain the overshoot as a systemic phenomenon
created by the limited information available and the bounded rationality
of the petroleum estimation experts. For example, the USGS assumed the
yield to exploration effort in unexplored areas of a given stratigraphy
would be the same as had historically been observed in the explored
regions of similar type. Sounds reasonable - if drilling activity was
randomly distributed. But drilling activity is far from random - oil
cos and wildcatters are several times better than random. This means
they found the easy stuff first, and the yield to exploration in the
places they havent yet looked must be lower on average than in the
places they have. Compound this error with long delays in getting and
adjusting beliefs about data on the yield to exploration and naive
extrapolation of progress in discovery and recovery technology and
youve got the basis for the overshoot.
Only one estimation method avoids the overshoot, and it is the method
developed by the late geologist M. King Hubbert. Hubberts method,
based on the basic stock-flow structure of the resource base, has
consistently proved to be the most accurate for the US. Indeed, in 1956
Hubbert predicted US lower 48 production would peak between 1968 and
1972 - at a time when the official and consensus view was that no limits
were in sight. Widely criticized at the time, Hubbert had the last
laugh when production peaked in 1970 (it is now about half that level).
Hubberts model is certainly one of the most accurate long-range
forecasts of all time.
Our models explain the accuracy of Hubberts method and the tendency for
overshoot by the geologic analogy method. The version of the model
calibrated for the world oil resource situation suggests an overshoot
for estimates of world oil in place as well.
The main point of our work was to show how system dynamics could be used
to calibrate methods to estimate an unknown resource base when the usual
method - repeated comparison of forecasts to actual outcomes - is
impossible. In the case of oil and other nonrenewable resources, the
true answer wont be known until the answer itself is moot - that is,
until after we have consumed the oil and have no chance to correct any
errors. There are policy implications, however. Overoptimistic
estimates of resource abundance can lead to complacency about how much
time remains to develop renewable substitutes for petroleum, dampen
conservation efforts, and delay development of the technologies,
institutions, and values needed to create a sustainable energy system
and sustainable society. I wonder what biases (optimistic or
pessimistic) remain to be discovered in the methods currently being used
to assess other, even more ambiguous, resources such as climate change,
soil fertility, and biodiversity.
Interested readers will find this work in:
Davidsen, P., Sterman, J. D., & Richardson, G. P. (1990). A Petroleum
Life Cycle Model for the United States with Endogenous Technology,
Exploration, Recovery, and Demand. System Dynamics Review, 6(1), 66-93.
- Describes the model we developed.
Sterman, J. D., & Richardson, G. P. (1985). An Experiment to Evaluate
Methods for Estimating Fossil Fuel Resources. Journal of Forecasting,
4(2), 197-226.
- Uses the model to examine the dynamics of global petroleum estimates.
Sterman, J. D., Richardson, G. P., & Davidsen, P. (1988). Modeling the
Estimation of Petroleum Resources in the United States. Technological
Forecasting and Social Change, 33(3), 219-249.
- Uses the model to examine the dynamics of petroleum estimates in the
USA.
John Sterman
jsterman@mit.edu
to the oil market, the topic of petroleum depletion is being
rediscovered.
The history of attempts to gauge the size of the petroleum resource base
is an interesting and contentious one. A few years ago, George
Richardson, Pal Davidson, and I developed system dynamics models of the
dynamics of estimates of world and US petroleum resources. The focus
was the accuracy over time of the estimation procedures used by various
groups (the USGS, oil cos, etc.) to guess at how much oil there is, and
how much is likely to be recoverable.
It is obvious that natures initial endowment of oil to humanity (known
as initial oil-in-place) is fixed relative to the human time scale (that
is, petroleum is formed over geologic time while consumed over only a
few hundred years, so relative to our time horizon, the petroleum
creation rate is essentially zero). It is also obvious that the amount
of oil remaining in the ground to be consumed in the future is
monotonically declining.
*Estimates* of initial oil in place, however, can rise or fall as
knowledge, opinions, methods, and political pressures change. There are
a variety of estimation methods. One of the most popular is the
"geologic analogy method" in which the abundance of oil in unexplored
regions is estimated by assuming it will be similar to that in known
regions of similar geology. Historically, as each region is opened to
exploration, the estimates start low, then rise rapidly as greater
exploration and improved geological knowledge lead to better estimates.
But instead of flattening out close to or asymptotically approaching the
"true" level, estimates in the US dramatically overshot and then
collapsed. In the 1960s the USGS estimated the ultimate recoverable
petroleum resource base to be nearly three times as great as the value
now widely accepted and endorsed by USGS. Why the overshoot? The
models we developed explain the overshoot as a systemic phenomenon
created by the limited information available and the bounded rationality
of the petroleum estimation experts. For example, the USGS assumed the
yield to exploration effort in unexplored areas of a given stratigraphy
would be the same as had historically been observed in the explored
regions of similar type. Sounds reasonable - if drilling activity was
randomly distributed. But drilling activity is far from random - oil
cos and wildcatters are several times better than random. This means
they found the easy stuff first, and the yield to exploration in the
places they havent yet looked must be lower on average than in the
places they have. Compound this error with long delays in getting and
adjusting beliefs about data on the yield to exploration and naive
extrapolation of progress in discovery and recovery technology and
youve got the basis for the overshoot.
Only one estimation method avoids the overshoot, and it is the method
developed by the late geologist M. King Hubbert. Hubberts method,
based on the basic stock-flow structure of the resource base, has
consistently proved to be the most accurate for the US. Indeed, in 1956
Hubbert predicted US lower 48 production would peak between 1968 and
1972 - at a time when the official and consensus view was that no limits
were in sight. Widely criticized at the time, Hubbert had the last
laugh when production peaked in 1970 (it is now about half that level).
Hubberts model is certainly one of the most accurate long-range
forecasts of all time.
Our models explain the accuracy of Hubberts method and the tendency for
overshoot by the geologic analogy method. The version of the model
calibrated for the world oil resource situation suggests an overshoot
for estimates of world oil in place as well.
The main point of our work was to show how system dynamics could be used
to calibrate methods to estimate an unknown resource base when the usual
method - repeated comparison of forecasts to actual outcomes - is
impossible. In the case of oil and other nonrenewable resources, the
true answer wont be known until the answer itself is moot - that is,
until after we have consumed the oil and have no chance to correct any
errors. There are policy implications, however. Overoptimistic
estimates of resource abundance can lead to complacency about how much
time remains to develop renewable substitutes for petroleum, dampen
conservation efforts, and delay development of the technologies,
institutions, and values needed to create a sustainable energy system
and sustainable society. I wonder what biases (optimistic or
pessimistic) remain to be discovered in the methods currently being used
to assess other, even more ambiguous, resources such as climate change,
soil fertility, and biodiversity.
Interested readers will find this work in:
Davidsen, P., Sterman, J. D., & Richardson, G. P. (1990). A Petroleum
Life Cycle Model for the United States with Endogenous Technology,
Exploration, Recovery, and Demand. System Dynamics Review, 6(1), 66-93.
- Describes the model we developed.
Sterman, J. D., & Richardson, G. P. (1985). An Experiment to Evaluate
Methods for Estimating Fossil Fuel Resources. Journal of Forecasting,
4(2), 197-226.
- Uses the model to examine the dynamics of global petroleum estimates.
Sterman, J. D., Richardson, G. P., & Davidsen, P. (1988). Modeling the
Estimation of Petroleum Resources in the United States. Technological
Forecasting and Social Change, 33(3), 219-249.
- Uses the model to examine the dynamics of petroleum estimates in the
USA.
John Sterman
jsterman@mit.edu
-
- Junior Member
- Posts: 11
- Joined: Fri Mar 29, 2002 3:39 am
oil and gas prices and reserves
>Jim Craig of the American Petroleum Institute says:
>
>"Sachs incorrectly reports "most of the worlds known oil reserves will be
>used up in 10 years", ... Let me cite the highly regarded U.S. Geological
>Survey, which estimates that between 1.4 trillion and 2.1 trillion barrels
>of oil remain to be produced worldwide (one barrel is equal to 42 gallons.
I havent seen the original of either article, but one source of confusion
may be the difference between reserves and resources. Jim Craig is clearly
talking about the oil resource - the ultimate recoverable quantity of oil
in the world. Resources clearly will last much more than a decade. Sachs is
apparently talking about reserves - the portion of the resource which has
been discovered and developed sufficiently for near-term production.
Reserves tend to remain relatively stable at 10 to 40 years of current
production - exploration deliberately maintains this ratio.
At the moment, some of the major oil companies are feeling a reserve pinch.
Middle East nations would prefer to exploit their resources themselves,
which doesnt leave much to go around for everyone else. Thats why theres
such a rush to develop alternatives in Asia. Many firms and regions likely
will be facing seriously depleted reserves in 10 years.
>"This estimate would sustain current consumption rates between 63 and 96
>years. In other words, theres a 95 percent possibility that the worlds
>remaining oil RESERVES could last 63 more years, and a 5 percent chance
>that the global RESOURCES will last another 95 years based on recent
>consumption."
Again, Craig uses reserves and resources as if they were interchangeable.
An API employee ought to know the difference.
The reserve
esource confusion has been around a long time. In Limits to
Growth, a table compared the SRLI (Static Reserve Life Index,
reserves/current_production) to the actual reserve lifetime taking growth
into account. The point of the table was about static vs. dynamic
expectations, not a forecast of reserve behavior. But ever since theres
been a parade of critics pointing out that reserves for most materials have
remained relatively constant or even grown. From that behavior, were
supposed to infer that theres no problem.
To replace 1990 oil consumption with horses, youd need about 6 billion of them:
1990 oil production 1.42e11 GigaJoules/year
x 31.7 watts/(GJ/yr) 4.50e12 watts
/ 745 watts/horsepower 6.03e9 horsepower
x 1 horse/horsepower ~ 6 billion horses
This must be at least 5 doublings. With growth, and the need to replace
gas, too, itll take a lot more. In the US, wed better plan on 5 to 10
horses each. Now I wish my wifes horses werent gelded.
Of course, this is a silly calculation, as you dont need 200 horses to get
to work, though many car owners seem to think that they do. For
space-heating applications, smaller animals like pigs or chickens might be
more convenient.
- Tom
______________________________________________________________
Thomas Fiddaman, PhD Candidate http://web.mit.edu/tomfid/www
MIT Sloan School of Management, System Dynamics Group
E60-355, 30 Memorial Drive, Cambridge, MA 02142
MIT: 617-253-3958 home: 603-497-2273 email: tomfid@mit.edu
______________________________________________________________
>
>"Sachs incorrectly reports "most of the worlds known oil reserves will be
>used up in 10 years", ... Let me cite the highly regarded U.S. Geological
>Survey, which estimates that between 1.4 trillion and 2.1 trillion barrels
>of oil remain to be produced worldwide (one barrel is equal to 42 gallons.
I havent seen the original of either article, but one source of confusion
may be the difference between reserves and resources. Jim Craig is clearly
talking about the oil resource - the ultimate recoverable quantity of oil
in the world. Resources clearly will last much more than a decade. Sachs is
apparently talking about reserves - the portion of the resource which has
been discovered and developed sufficiently for near-term production.
Reserves tend to remain relatively stable at 10 to 40 years of current
production - exploration deliberately maintains this ratio.
At the moment, some of the major oil companies are feeling a reserve pinch.
Middle East nations would prefer to exploit their resources themselves,
which doesnt leave much to go around for everyone else. Thats why theres
such a rush to develop alternatives in Asia. Many firms and regions likely
will be facing seriously depleted reserves in 10 years.
>"This estimate would sustain current consumption rates between 63 and 96
>years. In other words, theres a 95 percent possibility that the worlds
>remaining oil RESERVES could last 63 more years, and a 5 percent chance
>that the global RESOURCES will last another 95 years based on recent
>consumption."
Again, Craig uses reserves and resources as if they were interchangeable.
An API employee ought to know the difference.
The reserve
esource confusion has been around a long time. In Limits to
Growth, a table compared the SRLI (Static Reserve Life Index,
reserves/current_production) to the actual reserve lifetime taking growth
into account. The point of the table was about static vs. dynamic
expectations, not a forecast of reserve behavior. But ever since theres
been a parade of critics pointing out that reserves for most materials have
remained relatively constant or even grown. From that behavior, were
supposed to infer that theres no problem.
To replace 1990 oil consumption with horses, youd need about 6 billion of them:
1990 oil production 1.42e11 GigaJoules/year
x 31.7 watts/(GJ/yr) 4.50e12 watts
/ 745 watts/horsepower 6.03e9 horsepower
x 1 horse/horsepower ~ 6 billion horses
This must be at least 5 doublings. With growth, and the need to replace
gas, too, itll take a lot more. In the US, wed better plan on 5 to 10
horses each. Now I wish my wifes horses werent gelded.
Of course, this is a silly calculation, as you dont need 200 horses to get
to work, though many car owners seem to think that they do. For
space-heating applications, smaller animals like pigs or chickens might be
more convenient.
- Tom
______________________________________________________________
Thomas Fiddaman, PhD Candidate http://web.mit.edu/tomfid/www
MIT Sloan School of Management, System Dynamics Group
E60-355, 30 Memorial Drive, Cambridge, MA 02142
MIT: 617-253-3958 home: 603-497-2273 email: tomfid@mit.edu
______________________________________________________________
-
- Senior Member
- Posts: 54
- Joined: Fri Mar 29, 2002 3:39 am
oil and gas prices and reserves
Tom Fiddamans analysis of the impending horse shortage was terrific,
but he forgot that we dont need to worry about replacing the dwindling
supplies of natural gas because well be able to generate all the
methane we need from the gigatons of horse manure well be neck deep in.
John Sterman
jsterman@mit.edu
but he forgot that we dont need to worry about replacing the dwindling
supplies of natural gas because well be able to generate all the
methane we need from the gigatons of horse manure well be neck deep in.
John Sterman
jsterman@mit.edu