Articles tagged with "modeling"
This is a guest post by Steve Mohr, who recently received his PhD in Chemical Engineering at the University of Newcastle in Australia. He now works as a research consultant at the Institute for Sustainable Futures.
Last year I placed a summary of my PhD thesis on The Oil Drum. The thesis described a new model that projects fossil fuel (coal, conventional oil, unconventional oil, conventional gas, and unconventional gas) for all countries to determine the world’s fossil fuel supply and demand. At the time I did not make the model itself public, as it was written partially in C++ and partially in Maple. C++ is free; Maple, however, is expensive. In 2010 I was lucky enough to work with Dr Gavin Mudd and by extension the Institute for Sustainable Futures (ISF), and I was able to add a recycling component to the model enabling the model to be applied to the projections of metals.
In 2011, I commenced work at the ISF. Recently the ISF very kindly allowed me time to convert the model out of Maple and into Excel, in the process making the model easier to use, and freely available. As a result, the model was placed on the ISF website. It can be found at this link.
GeRS-DeMo - or Geologic Resource Supply - Demand Model estimates the demand, production (from mines or fields) and recycling of any geologic resource. The production from mines works by bringing idealised mines online throughout time and over time the supply and demand interactions allow more or less mines to come online and also mines to shut down earlier than expected (and restart later) or upgrade the mines (by doubling the mines production). The production from fields works by putting idealised fields online as shown in Figure 1. The sizes of the fields vary, with initial fields being relatively large, and a final fields being relatively small. Due to the variability in sizes, all fields in a given region are assumed to have two constant ratios (inputted) one between the maximum production to the Ultimately Recoverable Resources (URR), and the other for the URR remaining when production begins to decline relative to the URR.
This is a guest post by Roger Fouquet, Ikerbasque Research Professor at the Basque Center for Climate Change best known for his book Heat, Power, and Light: Revolutions in Energy Services. The post builds upon Fouquet, R. 2011a. Divergences in the Long Run Trends in the Price of Energy and of Energy Services. Review of Environmental Economics and Policy 5(2). 186-218.
His research shows that it is not the price of energy input (depletion) which matters for the economy, but the cost of energy input per unit of output (depletion + technology). Something which seems obvious but is often forgotten in the energy discussion. Also at The Oil Drum we often erroneously talk about effects of the oil price on the economy, and not the cost of an oil or energy service delivered to the economy. The latter not being affected just by energy prices, but by all inputs and the efficiency and cost.
Energy prices have risen considerably since the beginning of the twenty-first century. It is valuable to place these price rises within a historical context. Many peaks preceded the price hike of 2008, and there will, no doubt, be many more. However, if future trends follow past ones, then it is tempting to conclude that the long-run trend in individual and average energy prices will be generally stable or downwards.
This note also highlights the tendency for long-run trends in the price of energy and of energy services to diverge. That is, since the Industrial Revolution, energy efficiency improvements have led the price of energy services to fall far more than the decline in the price of energy. This is an important distinction because commentators have a tendency to focus on energy prices, even though consumers are ultimately interested in the services that energy provide, such as space and water heating or cooling, powering of appliances, illumination and transportation (Goldemberg et al. 1985). This divergence in the long-run has major implications for forecasts of future energy use and carbon dioxide emissions, welfare improvements and the evolution of economies.
It is clear there are limits to the pollution a given ecosystem can absorb, the level of resources that can be depleted, and debt that can be incurred. Despite concerns of many about these limits we are far from tackling any of these problems on a meaningful scale. The question is why this is the case and if we (the Human Race) have the knowledge and capability to live within such limits on Planet Earth?
In this post, different modeling approaches to gain insights into sustainability will be discussed. We hope that readers will contribute their thinking of what a sustainable ecosystem would look like, and how to map the road towards it. One of the parts of this post is the initial outline of a project to model a human ecosystem from cradle to grave. This project will be carried out by the Institute for Integrated Economic Research (IIER), an institute in which Nate Hagens and myself are involved. Also IIER is looking for individuals to participate in this project, and encourages anyone with a passion for working on resources and energy consumption to take a look at our job advert and contact us via recruiting at iier dot ch.
This is a guest post from Dolores García, an independent researcher based in Brighton, UK.
Recently Jorgen Randers (best known for being one of the co-authors of The Limits to Growth, 1972) asked me to do some modelling work on the World3-Energy model, an updated version of the classic World3 computer model that was used in The Limits to Growth that includes a much larger amount of information about energy. He’d like to use it for the next book that he intends to publish sometime in 2012.
I have published on The Oil Drum before the details of World3-Energy (a dynamic systems model), can be found in:
And a few answers to reader’s questions can be found here:
Part of the work I’m doing for Jorgen Randers is comparing the results of World3-Energy with IEA’s results. I thought the readers of The Oil Drum would be interested in this.
This is a letter I received from a reader (with the name changed). Below the fold is an expanded version of my answer to him. I would be interested in what other people's thoughts are on this subject as well.
My name is John Smith. I have been following the peak oil situation since about 2005. A few years back I thought I had a handle on what I could expect from peak oil. Then, the recession hit, and changed (delayed) everything.
My problem is, I have not seen an rigorous peak oil studies/projections that take recent events into account on peak oil projections going forward. As an expert on the subject, could you please point me to some literature that would be of help?
I do not know what the future holds, but it is clear to me that realities have changed, and with it, the timeline of peak oil.
When I published the results on The Oil Drum of my New World Model, based on World3 (the “Limits to Growth” model) – see here, many of the questions and issues that people had were around EROEI. So I’m writing this article to clarify how the model uses EROEI and the results in some alternative scenarios where EROEI is changed in different ways.
Total energy production and industrial output in the New World Model.
The paper is under the fold. We have tried to render the article in HTML, but it is difficult to make the formatting as perfect as when it is typeset. Please accept our apologies. A PDF version of the article can be downloaded here, if you prefer that format.
Posted by Chris Vernon on April 3, 2009 - 10:18am in The Oil Drum: Europe
Tags: climate change, energy, limits to growth, modeling, population, resources [list all tags]
Abstract: An updated systems model of global climate, resources, and energy extending the original World3 (“Limits to Growth”) model by inclusion of climate change and it's interaction with resources and energy. Outcomes are derived for total energy resources, human population, nutrition, consumption, economic activity and other parameters. Long-term outcomes are derived for a 1900 C.E. to 2100 C.E. time sequence, with human population decline.
Seven am breakfasts in O’Hare are not a habit I plan on developing but there was I, for the second day running, at the same table even at Wolfgang Pucks.. But all in a good cause, as I headed off to Houston for ASPO. Going to the hotel - very new and needed, as the cabby proudly told me,– he asked which Convention I was here for (there is an Olympics meeting of some sort down the hall). I explained about Peak Oil and though initially he had not heard about it, he then mentioned a Houston City Council effort to have the cab companies use hybrids. This is now on hold, since it did not appear to be a well-received suggestion. Concerns that he brought up included the small size of the cars, that they were only 4-cylinder and would not stand the wear that a cab life would impose, and that the cabbies, who have to buy the cabs, could not afford the $3,000 to replace the batteries. Apparently the cab companies had suggested that they would comply right after the police Department bought theirs. Talking at an ASPO break about this, apparently Denver are experimenting with the process, but have only just introduced it with a few cabs., and a quick Google shows that a number of cities have already bitten that bullet.
With getting here a little late I walked into the first joint sessions after they had started, and, as with the ASPO in Cork, the atmosphere immediately conveyed that the meeting would be a success. (Though the initial judgment was made because I had to drop my bag and lean against the wall since there were no free seats, and when more were brought they were still not enough). The audience was obviously knowledgeable and the questions were technical, as were the answers. For the first “Workshop” day the sessions were divided, with TOD stalwarts Stuart Staniford and Euan Mearns giving the story of their incredible detective work in, as an audience member put it, developing the story of Saudi oil with virtually none of the resources or computing power of Aramco, and yet coming very close to what has to be the real story. Stuart explained how the numbers that he, and others at TOD, had put together and painted the picture of Ghawar depletion, (which is in the citation so I won’t repeat it) and Euan put this in the broader context of Saudi Arabia in general. Gail Tverberg acted as moderator to the session and the discussion. Perhaps the crux of the issue is that the authors do not think that Saudi Aramco can produce the volumes that they claim for Ghawar since, in part they assume a higher recovery factor that has been historically true for this type of rock, and with around half the production gone, things are not looking all that good. Reference was made in questions to other papers coming in the meeting that will bring further light to the topic, including such a comment from Matt Simmons.
Roger Bentley has written Global Oil and Gas Depletion - A Letter to the Energy Modelling Community, published by the Energy Economics Education Foundation (The IAEE's education affiliate) and available to download here (.pdf, page 6).
Bentley addresses this letter to the energy modelling community, it is a brief summary of the various approaches and highlights the problems of the past. A fundamental difficulty surrounds the two different data sets of P50 and proved reserves, the use of proved reserves in the mistaken belief they are a reasonable measure of the remaining oil being chiefly responsible for the difficulties.
‘P50’ designates 50% probable, and is an industry estimate at a given date for the most likely size of a field’s reserves. P50 estimates are often approximated quite well by ‘proved plus probable’ reserves.
[Proved reserves] are quite unusable for calculating future oil production as they exhibit serious errors of under-reporting, over-reporting, and non-reporting. These data problems have not been adequately recognised by much of the energy modelling community, leading to serious errors of analysis.