Does energy consumption follow a Gaussian curve? (long)
Question:
Hello again, Thank you, Graham and R.H for your references. The paper by Grubler et al might say something about the shape of the energy consumption curve. I will try to order it from the local university library. As for boron, I guess it is just a way of storing energy for transportation, a bit like hydrogen or metal based fuel cells or hydrocarbons for that matter. The choice of storage medium will say something about the practicality and the overall efficiency of the process. It will also say something about the vehicle topology and efficiency, e.g. I guess that boron might be best suited for thermomechanical engines (steam engine, turbine, Stirling), whereas metal fuel cells probably will be better suited for electrical engines. While waiting for more data, I will try to make some very crude math to correct the "life times" of the non-actinid fossil fuels. I haven’t done any work on actinids. If someone finds any flaws in my calculations, I would be grateful for feedback. If consumed at the present rate, oil is claimed to last for about 45 years, natural gas for 70 years and coal for 225 years. In 1996, world consumption of fossil fuels was made up by 43% oil, 27% natural gas and 29% coal (based on energy contents). For data on reserves, see references at http://www.coal.ca/class.htm http://ch-www.st-and.ac.uk/~jac/teaching/CH1002old/lect1.html (section 1.3) and use optimistic estimates For data on the "mix" of fossil fuels used in 1996, see http://www.ec.gc.ca/Ind/english/Energy/Tables/ectb07_e.cfm If we replace oil entirely by gas after the first 45 years, we will run out of it 2.6 times faster, i.e. less than 10 years later or 55 years from now. That leaves us with 170 years of coal at the present rate of consumption. If we use coal to replace oil and gas, we will run out of it 3.4 times faster, i.e. about 50 years later or in year 2105 or so. That sounds like uncannily near future to me although I will be long gone when that time comes. Electricity production from coal is much less efficient than production from natural gas. Production of transportation fuels from coal and natural gas (e.g. by Fischer-Tropsch) is probably somewhat less efficient than production from oil, so the numbers above may be slightly optimistic. On the other hand the waste heat obtained from inefficient processes can be used for heating of residential areas so the energy need not be entirely wasted. The efficiency of electricity production is 50 – 60 % for gas power plants and 40% for coal power plants. For references, see http://ch-www.st-and.ac.uk/~jac/teaching/CH1002old/lect3.html (section 5) http://ch-www.st-and.ac.uk/~jac/teaching/CH1002old/lect4.html (section 4) With a Gaussian shape, speaking of the life time of a certain fuel becomes irrelevant, but it is of course of some interest to know the area under the curve. Best regards, Mikael Hammer
Response:
From the cheap seats, "New ideas in science are not always right just because they are new. Nor are the old ideas always wrong just because they are old. A critical attitude is clearly required of every scientist. But what is required is to be equally critical to the old ideas as to the new. Whenever the established ideas are accepted uncritically, but conflicting new evidence is brushed aside and not reported because it does not fit, then that particular science is in deep trouble – and it has happened quite often in the historical past. If we look over the history of science, there are very long periods when the uncritical acceptance of the established ideas was a real hindrance to the pursuit of the new. Our period is not going to be all that different in that respect, I regret to say." www.eskimo.com/~billb/freenrg/newidea1.html Considering your posting, and noting that it did invite "without prejudice" commentary. I do not believe that we can truly understand the ecoeconomics of a consumption/supply model without defining the true nature of the supply. The existing theories surrounding the source of fossil fuel supply is being questioned by alternate theories. We cannot overlook that there may be a sustainable consumption levels of fossil fuels, which incorporates the renewable level of supply, with a holistic waste management and pollution controls. The basis of the fossil fuel generation model is the carbon cycle. Traditional thought concerning the geochemical time frame regarding coal has somehow prejudiced the case for both oil and gas. Certainly, there are oil and natural gas which are "fossil fuels", however, there is considerable evidence to suggest that oil and natural gas are also generated by, less understood mechanisms, which generate a renewable supply of hydrocarbons, acting over much shorter time frames, perhaps just years! This leads to some important questions. 1) What mechanisms are driving the renewability of oil and natural gas? 2) What is the total renewability of this source? 3) What portion of this supply is accessible? 3) What are the impacts of this on pricing and other issues such as conservation and pollution? 4) What are the environmental implications? Anyone want to touch this? ;-> — Duane Tilden Society of Energy & Resources for Sustainable Development
– Hide quoted text — Show quoted text -> Hello, > This posting is a test of a speculative theory on energy consumption > which suggests that energy consumption may follow the Gaussian bell > curve indicated by the so-called Hubbert model for oil production and > that the "life expectancy" of the important energy sources, and our > industrialized society may therefore be shorter than indicated by > published estimates (assuming that environmental effects or political > decisions do not intervene, of course). > I do not pretend to have any stringent theoretical model or hard facts > to support my theory, but I don’t have enough knowledge or data to > "shoot it down" either. Maybe someone out there can help me out. > Any inputs, improvements to my theory, proofs or well founded > argumentation against it would be most welcome. Hints to literature or > websites where someone has already discussed relevant subjects would > also be welcome. > 1. The Hubbert model for oil production > (Production in this context really means exploitation or exhaustion of > the available, finite resource, of course, i.e. consumption would be a > better word for it, but I use the terminology of the reference from > Scientific American listed below) > A couple of years ago, there was an interesting article in Scientific > American (C.J. Campbell & J.H.Laherr
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